SIST EN 302 307 V1.2.1:2009
(Main)Digital Video Broadcasting (DVB) - Second generation framing structure, channel coding and modulation systems for Broadcasting, Interactive Services, News Gathering and other broadband satellite applications (DVB-S2)
Digital Video Broadcasting (DVB) - Second generation framing structure, channel coding and modulation systems for Broadcasting, Interactive Services, News Gathering and other broadband satellite applications (DVB-S2)
DVB-S (EN 300 421 [2]) was introduced as a standard in 1994 and DVB-DSNG (EN 301 210 [3]) in 1997. The DVB-S standard specifies QPSK modulation and concatenated convolutional and Reed-Solomon channel coding, and is now used by most satellite operators worldwide for television and data broadcasting services. DVB-DSNG specifies, in addition to DVB-S format, the use of 8PSK and 16QAM modulation for satellite news gathering and contribution services.
Digitalna videoradiodifuzija (DVB) - Druga generacija strukture okvirov, kodiranja kanalov in modulacijskih sistemov za radiodifuzijo, interaktivne storitve, novinarstvo in druge širokopasovne satelitske aplikacije
General Information
Standards Content (Sample)
Final draft ETSI EN 302 307 V1.2.1 (2009-04)
European Standard (Telecommunications series)
Digital Video Broadcasting (DVB);
Second generation framing structure, channel coding and
modulation systems for Broadcasting,
Interactive Services, News Gathering and
other broadband satellite applications (DVB-S2)
European Broadcasting Union Union Européenne de Radio-Télévision
EBU·UER
2 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
Reference
REN/JTC-DVB-238
Keywords
BSS, digital, DVB, modulation, satellite, TV
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ETSI
3 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
Contents
Intellectual Property Rights.5
Foreword.5
1 Scope.6
2 References.8
2.1 Normative references.8
2.2 Informative references.9
3 Symbols and abbreviations.9
3.1 Symbols.9
3.2 Abbreviations.10
4 Transmission system description.12
4.1 System definition.12
4.2 System architecture.12
4.3 System configurations.13
5 Subsystems specification.14
5.1 Mode adaptation.14
5.1.1 Input interface.14
5.1.2 Input stream synchronizer (optional, not relevant for single TS - BS) .15
5.1.3 Null-Packet Deletion (ACM and Transport Stream only) .15
5.1.4 CRC-8 encoder (for packetized streams only).15
5.1.5 Merger/Slicer.16
5.1.6 Base-Band Header insertion .17
5.2 Stream adaptation.19
5.2.1 Padding.19
5.2.2 BB scrambling.19
5.3 FEC encoding.20
5.3.1 Outer encoding (BCH).21
5.3.2 Inner encoding (LDPC) .22
5.3.2.1 Inner coding for normal FECFRAME.22
5.3.2.2 Inner coding for short FECFRAME.23
5.3.3 Bit Interleaver (for 8PSK, 16APSK and 32APSK only).24
5.4 Bit mapping into constellation.25
5.4.1 Bit mapping into QPSK constellation.25
5.4.2 Bit mapping into 8PSK constellation.26
5.4.3 Bit mapping into 16APSK constellation.26
5.4.4 Bit mapping into 32APSK .27
5.5 Physical Layer (PL) framing .28
5.5.1 Dummy PLFRAME insertion.29
5.5.2 PL signalling.29
5.5.2.1 SOF field.30
5.5.2.2 MODCOD field.30
5.5.2.3 TYPE field.30
5.5.2.4 PLS code.30
5.5.3 Pilots insertion.31
5.5.4 Physical layer scrambling .31
5.6 Baseband shaping and quadrature modulation .33
6 Error performance .34
Annex A (normative): Signal spectrum at the modulator output.35
Annex B (normative): Addresses of parity bit accumulators for n = 64 800.37
ldpc
Annex C (normative): Addresses of parity bit accumulators for n = 16 200.47
ldpc
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4 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
Annex D (normative): Additional Mode Adaptation and ACM tools .50
D.1 "ACM Command" signalling interface .50
D.2 Input stream synchronizer .50
D.3 Null-packet Deletion (normative for input transport streams and ACM).52
D.4 BBHEADER and Merging/slicing Policy for various application areas.53
D.5 Signalling of reception quality via return channel (Normative for ACM).54
Annex E (normative): SI and signal identification for DSNG and contribution applications .56
Annex F (normative): Backwards Compatible modes (optional).57
Annex G (informative): Supplementary information on receiver implementation .60
G.1 Carrier recovery.60
G.2 FEC decoding.60
G.3 ACM: Transport Stream regeneration and clock recovery using ISCR .63
G.4 Non linearity pre-compensation and Intersymbol Interference suppression techniques .63
G.5 Interactive services using DVB-RCS return link: user terminal synchronization.64
Annex H (informative): Examples of possible use of the System.65
H.1 CCM digital TV broadcasting: bit rate capacity and C/N requirements .65
H.2 Distribution of multiple TS multiplexes to DTT Transmitters (Multiple TS, CCM).67
H.3 SDTV and HDTV broadcasting with differentiated protection (VCM, Multiple TS) .68
H.4 DSNG Services using ACM (Single transport Stream, information rate varying in time) .68
H.5 IP Unicast Services (Non-uniform protection on a user-by-user basis) .69
H.6 Example performance of BC modes.71
H.7 Satellite transponder models for simulations .72
H.8 Phase noise masks for simulations .74
Annex I (normative): Mode Adaptation input interfaces (optional).75
I.1 Mode Adaptation input interface with separate signalling circuit (optional).75
I.2 Mode Adaptation input interface with in-band signalling (optional).76
Annex L (informative): Bibliography.77
History .78
ETSI
5 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This European Standard (Telecommunications series) has been produced by Joint Technical Committee (JTC)
Broadcast of the European Broadcasting Union (EBU), Comité Européen de Normalisation ELECtrotechnique
(CENELEC) and the European Telecommunications Standards Institute (ETSI), and is now submitted for the ETSI
standards One-step Approval Procedure.
The work of the JTC was based on the studies carried out by the European DVB Project under the auspices of
theAd Hoc Group on DVB-S2 of the DVB Technical Module. This joint group of industry, operators and broadcasters
provided the necessary information on all relevant technical matters (see bibliography).
NOTE: The EBU/ETSI JTC Broadcast was established in 1990 to co-ordinate the drafting of standards in the
specific field of broadcasting and related fields. Since 1995 the JTC Broadcast became a tripartite body
by including in the Memorandum of Understanding also CENELEC, which is responsible for the
standardization of radio and television receivers. The EBU is a professional association of broadcasting
organizations whose work includes the co-ordination of its members' activities in the technical, legal,
programme-making and programme-exchange domains. The EBU has active members in about
60 countries in the European broadcasting area; its headquarters is in Geneva.
European Broadcasting Union
CH-1218 GRAND SACONNEX (Geneva)
Switzerland
Tel: +41 22 717 21 11
Fax: +41 22 717 24 81
Founded in September 1993, the DVB Project is a market-led consortium of public and private sector organizations in
the television industry. Its aim is to establish the framework for the introduction of MPEG-2 based digital television
services. Now comprising over 200 organizations from more than 25 countries around the world, DVB fosters
market-led systems, which meet the real needs, and economic circumstances, of the consumer electronics and the
broadcast industry.
Proposed national transposition dates
Date of latest announcement of this EN (doa): 3 months after ETSI publication
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 6 months after doa
Date of withdrawal of any conflicting National Standard (dow): 6 months after doa
ETSI
6 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
1 Scope
DVB-S (EN 300 421 [2]) was introduced as a standard in 1994 and DVB-DSNG (EN 301 210 [3]) in 1997. The DVB-S
standard specifies QPSK modulation and concatenated convolutional and Reed-Solomon channel coding, and is now
used by most satellite operators worldwide for television and data broadcasting services. DVB-DSNG specifies, in
addition to DVB-S format, the use of 8PSK and 16QAM modulation for satellite news gathering and contribution
services.
Since 1997, digital satellite transmission technology has evolved somewhat:
• New channel coding schemes, combined with higher order modulation, promise more powerful alternatives to
the DVB-S/DVB-DSNG coding and modulation schemes. The result is a capacity gain in the order of 30 % at
a given transponder bandwidth and transmitted EIRP, depending on the modulation type and code rate.
• Variable Coding and Modulation (VCM) may be applied to provide different levels of error protection to
different service components (e.g. SDTV and HDTV, audio, multimedia).
• In the case of interactive and point-to-point applications, the VCM functionality may be combined with the use
of return channels, to achieve Adaptive Coding and Modulation (ACM). This technique provides more exact
channel protection and dynamic link adaptation to propagation conditions, targeting each individual receiving
terminal. ACM systems promise satellite capacity gains of up to 100 % - 200 %. In addition, service
availability may be extended compared to a constant protection system (CCM) such as DVB-S or
DVB-DSNG. Such gains are achieved by informing the satellite up-link station of the channel condition
(e.g. C/N+I) of each receiving terminal via the satellite or terrestrial return channels.
• DVB-S and DVB-DSNG are strictly focused on a unique data format, the MPEG Transport Stream
(ISO/IEC 13818-1 [1] or a reference to it). Extended flexibility to cope with other input data formats (such as
multiple Transport Streams, or generic data formats) is now possible without significant complexity increase.
The present document defines a "second generation" modulation and channel coding system (denoted the "System" or
"DVB-S2" for the purposes of the present document) to make use of the improvements listed above. DVB-S2 is a
single, very flexible standard, covering a variety of applications by satellite, as described below. It is characterized by:
• a flexible input stream adapter, suitable for operation with single and multiple input streams of various formats
(packetized or continuous);
• a powerful FEC system based on LDPC (Low-Density Parity Check) codes concatenated with BCH codes,
allowing Quasi-Error-Free operation at about 0,7 dB to 1 dB from the Shannon limit, depending on the
transmission mode (AWGN channel, modulation constrained Shannon limit);
• a wide range of code rates (from 1/4 up to 9/10); 4 constellations, ranging in spectrum efficiency from
2 bit/s/Hz to 5 bit/s/Hz, optimized for operation over non-linear transponders;
• a set of three spectrum shapes with roll-off factors 0,35, 0,25 and 0,20;
• Adaptive Coding and Modulation (ACM) functionality, optimizing channel coding and modulation on a
frame-by-frame basis.
The System has been optimized for the following broadband satellite applications:
Broadcast Services (BS) Digital multi-programme Television (TV)/High Definition Television (HDTV)
Broadcasting services to be used for primary and secondary distribution in the Fixed Satellite Service (FSS) and the
Broadcast Satellite Service (BSS) bands.
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7 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
DVB-S2 is intended to provide Direct-To-Home (DTH) services for consumer Integrated Receiver Decoder (IRD), as
well as collective antenna systems (Satellite Master Antenna Television - SMATV) and cable television head-end
stations (possibly with remodulation, see EN 300 429 [5]). DVB-S2 may be considered a successor to the current
DVB-S standard EN 300 421 [2], and may be introduced for new services and allow for a long-term migration. BS
services are transported in MPEG Transport Stream format. VCM may be applied on multiple transport stream to
achieve a differentiated error protection for different services (TV, HDTV, audio, multimedia). Two modes are
available:
• NBC-BS (Non Backwards Compatible Broadcast Services) is not backwards-compatible with EN 300 421 [2].
• BC-BS (Backwards-Compatible Broadcast Services) is backwards-compatible to EN 300 421 [2]
(see annex F).
In fact, with a large number of DVB-S receivers already installed, backwards compatibility may be required for a period
of time, where old receivers continue to receive the same capacity as before, while the new DVB-S2 receivers could
receive additional capacity broadcasts. When the complete receiver population has migrated to DVB-S2, the transmitted
signal can be modified to a non-backward compatible mode, thus exploiting the full potential of DVB-S2. To facilitate
the reception of DVB-S services by DVB-S2 receivers, implementation of DVB-S in DVB-S2 chips is highly
recommended.
Interactive Services (IS) Interactive data services including Internet access
DVB-S2 is intended to provide interactive services to consumer IRDs and to personal computers, where DVB-S2's
forward path supersedes the current DVB-S standard EN 300 421 [2] for interactive systems. The return path can be
implemented using various DVB interactive systems, such as DVB-RCS (EN 301 790 [6]), DVB-RCP
(ETS 300 801 [7]), DVB-RCG (EN 301 195 [8]), DVB-RCC (ES 200 800 [9]). Data services are transported in (single
or multiple) Transport Stream format according to EN 301 192 [4] (e.g. using Multiprotocol Encapsulation), or in
(single or multiple) generic stream format. DVB-S2 can provide Constant Coding and Modulation (CCM), or Adaptive
Coding and Modulation (ACM), where each individual satellite receiving station controls the protection mode of the
traffic addressed to it. Input Stream Adaptation for ACM is specified in annex D.
Digital TV Contribution and Satellite News Gathering (DTVC/DSNG)
Digital television contribution applications by satellite consist of point-to-point or point-to-multipoint transmissions,
connecting fixed or transportable uplink and receiving stations. They are not intended for reception by the general
public. According to ITU-R Recommendation SNG.770-1 [10], SNG is defined as "Temporary and occasional
transmission with short notice of television or sound for broadcasting purposes, using highly portable or transportable
uplink earth stations .". Services are transported in single (or multiple) MPEG Transport Stream format. DVB-S2 can
provide Constant Coding and Modulation (CCM), or Adaptive Coding and Modulation (ACM). In this latter case, a
single satellite receiving station typically controls the protection mode of the full multiplex. Input Stream Adaptation for
ACM is specified in annex D.
Data content distribution/trunking and other professional applications (PS)
These services are mainly point-to-point or point-to-multipoint, including interactive services to professional head-ends,
which re-distribute services over other media. Services may be transported in (single or multiple) generic stream format.
The system can provide Constant Coding and Modulation (CCM), Variable Coding and Modulation (VCM) or
Adaptive Coding and Modulation (ACM). In this latter case, a single satellite receiving station typically controls the
protection mode of the full TDM multiplex, or multiple receiving stations control the protection mode of the traffic
addressed to each one. In either case, interactive or non-interactive, the present document is only concerned with the
forward broadband channel.
DVB-S2 is suitable for use on different satellite transponder bandwidths and frequency bands. The symbol rate is
matched to given transponder characteristics, and, in the case of multiple carriers per transponder (FDM), to the
frequency plan adopted. Examples of possible DVB-S2 use are given in clause H.1.
Digital transmissions via satellite are affected by power and bandwidth limitations. Therefore DVB-S2 provides for
many transmission modes (FEC coding and modulations), giving different trade-offs between power and spectrum
efficiency (see clause H.1). For some specific applications (e.g. broadcasting) modes such as QPSK and 8PSK, with
their quasi-constant envelope, are appropriate for operation with saturated satellite power amplifiers (in single carrier
per transponder configuration). When higher power margins are available, spectrum efficiency can be further increased
to reduce bit delivery cost. In these cases also 16APSK and 32APSK can operate in single carrier mode close to the
satellite HPA saturation by pre-distortion techniques. All the modes are appropriate for operation in quasi-linear
satellite channels, in multi-carrier Frequency Division Multiplex (FDM) type applications.
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8 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
DVB-S2 is compatible with Moving Pictures Experts Group (MPEG-2 and MPEG-4) coded TV services (see
ISO/IEC 13818-1 [1]), with a Transport Stream packet multiplex. Multiplex flexibility allows the use of the
transmission capacity for a variety of TV service configurations, including sound and data services. All service
components are Time Division Multiplexed (TDM) on a single digital carrier.
The present document:
• gives a general description of the DVB-S2 system;
• specifies the digitally modulated signal in order to allow compatibility between pieces of equipment developed
by different manufacturers. This is achieved by describing in detail the signal processing principles at the
modulator side, while the processing at the receive side is left open to different implementation solutions.
However, it is necessary in the present document to refer to certain aspects of reception;
• identifies the global performance requirements and features of the System, in order to meet the service quality
targets.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• Non-specific reference may be made only to a complete document or a part thereof and only in the following
cases:
- if it is accepted that it will be possible to use all future changes of the referenced document for the
purposes of the referring document;
- for informative references.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated
references, only the edition cited applies. For non-specific references, the latest edition of the referenced document
(including any amendments) applies.
[1] ISO/IEC 13818 (parts 1 and 2): "Information technology - Generic coding of moving pictures and
associated audio information".
[2] ETSI EN 300 421 (V.1.1.2): "Digital Video Broadcasting (DVB); Framing structure, channel
coding and modulation for 11/12 GHz satellite services".
[3] ETSI EN 301 210: "Digital Video Broadcasting (DVB); Framing structure, channel coding and
modulation for Digital Satellite News Gathering (DSNG) and other contribution applications by
satellite".
[4] ETSI EN 301 192: "Digital Video Broadcasting (DVB); DVB specification for data broadcasting".
[5] ETSI EN 300 429: "Digital Video Broadcasting (DVB); Framing structure, channel coding and
modulation for cable systems".
[6] ETSI EN 301 790: "Digital Video Broadcasting (DVB); Interaction channel for satellite
distribution systems".
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9 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
[7] ETSI ETS 300 801: "Digital Video Broadcasting (DVB); Interaction channel through Public
Switched Telecommunications Network (PSTN)/ Integrated Services Digital Networks (ISDN)".
[8] ETSI EN 301 195: "Digital Video Broadcasting (DVB); Interaction channel through the Global
System for Mobile communications (GSM)".
[9] ETSI ES 200 800: "Digital Video Broadcasting (DVB); DVB interaction channel for Cable TV
distribution systems (CATV)".
[10] ITU-R Recommendation SNG.770-1: "Uniform operational procedures for satellite news gathering
(SNG)".
[11] ETSI ETS 300 802: "Digital Video Broadcasting (DVB); Network-independent protocols for DVB
interactive services".
2.2 Informative references
The following referenced documents are not essential to the use of the present document but they assist the user with
regard to a particular subject area. For non-specific references, the latest version of the referenced document (including
any amendments) applies.
[i.1] ETSI TS 102 005: "Digital Video Broadcasting (DVB); Specification for the use of Video and
Audio Coding in DVB services delivered directly over IP protocols".
[i.2] ETSI EN 300 744: "Digital Video Broadcasting (DVB); Framing structure, channel coding and
modulation for digital terrestrial television".
[i.3] ETSI TR 101 154: "Digital Video Broadcasting (DVB); Implementation guidelines for the use of
MPEG-2 Systems, Video and Audio in satellite, cable and terrestrial broadcasting applications".
[i.4] ETSI TR 101 162: "Digital Video Broadcasting (DVB); Allocation of Service Information (SI)
codes for DVB systems".
3 Symbols and abbreviations
3.1 Symbols
For the purposes of the present document, the following symbols apply:
α Roll-off factor
γ Ratio between constellation radii for 16APSK and 32APSK
c codeword
C/N Carrier-to-noise power ratio (N measured in a bandwidth equal to symbol rate)
C/N+I Carrier-to-(Noise+Interference) ratio
d ,d ,., d ,d
n −k −1 n −k −2 1 0
bch bch bch bch
BCH code redundancy bits
d(x) BCH code remainder of the division between the generator polynomial and
n −k
bch bch
x
m(x)
DFL Data Field Length
dmin LDPC code minimum distance
E /N Ratio between the energy per information bit and single sided noise power
b 0
spectral density
E /N Ratio between the energy per transmitted symbol and single sided noise power
s 0
spectral density
f Nyquist frequency
N
f Carrier frequency
G PLS code generator matrix
g(x) code generator polynomial
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10 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
g (x), g (x), …, g (x) polynomials to obtain BCH code generator polynomial
1 2 12
i LDPC code information block
i ,i ,.,i LDPC code information bits
0 1 k −1
ldpc
H(f) RC filters frequency transfer function
H LDPC code parity check matrix
(n-k)xn
I, Q In-phase, Quadrature phase components of the modulated signal
K number of bits of BCH uncoded Block
bch
N number of bits of BCH coded Block
bch
k number of bits of LDPC uncoded Block
ldpc
n number of bits of LDPC coded Block
ldpc
η PLFRAMING efficiency
η code efficiency
c
η number of transmitted bits per constellation symbol
MOD
η System spectral efficiency
tot
m BCH code information word
m(x) BCH code message polynomial
m , m ,.,m , m BCH code information bits
k −1 k −2 1 0
bch bch
M number of modulated symbols in SLOT
p , p ,.p LDPC code parity bits
0 1 n −k −1
ldpc ldpc
P number of pilot symbols in a pilot block
q code rate dependant constant for LDPC codes
θ deviation angle in hierarchical constellations
r In-band ripple (dB)
m
R Symbol rate corresponding to the bilateral Nyquist bandwidth of the
s
modulated signal
R Useful bit rate at the DVB-S2 system input
u
S Number of Slots in a XFECFRAME
T Symbol period
s
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
8PSK 8-ary Phase Shift Keying
16APSK 16-ary Amplitude and Phase Shift Keying
32APSK 32-ary Amplitude and Phase Shift Keying
ACM Adaptive Coding and Modulation
ASI Asynchronous Serial Interface
AWGN Additive White Gaussian Noise
BB BaseBand
BC Backwards-Compatible
NOTE: Referred to the system allowing partial stream reception by DVB-S receivers.
BCH Bose-Chaudhuri-Hocquenghem multiple error correction binary block code
BER Bit Error Ratio
B Bandwidth of the frequency Slot allocated to a service
S
BS Broadcast Service
BSS Broadcast Satellite Service
BW BandWidth (at -3 dB) of the transponder
CBR Constant Bit Rate
CCM Constant Coding and Modulation
CNI Carrier to Noise plus Interference ratio
CRC Cyclic Redundancy Check
D Decimal notation
DD Decision Directed
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11 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
DEMUX DEMUltipleXer
DF Data Field
DNP Deleted Null Packets
DSNG Digital Satellite News Gathering
DTH Direct To Home
DTT Digital Terrestrial Television
DVB Digital Video Broadcasting project
DVB-S DVB System for satellite broadcasting
NOTE: As specified in EN 300 421 [2].
DVB-S2 second generation DVB System for satellite broadcasting and unicasting
NOTE: As specified in the present document.
EBU European Broadcasting Union
EN European Norm
FDM Frequency Division Multiplex
FEC Forward Error Correction
FIFO First In First Out
FSS Fixed Satellite Service
GF Galois Field
GS Generic Stream
HDTV High Definition TeleVision
HEX HEXadecimal notation
HP High Priority
IBO Input Back Off
IF Intermediate Frequency
IMUX Input MUltipleXer - filter
IRD Integrated Receiver Decoder
IS Interactive Services
ISCR Input Stream Clock Reference
ISI Input Stream Identifier
ISSY Input Stream SYnchronizer
ISSYI Input Stream SYnchronizer Indicator
ITU International Telecommunications Union
LDPC Low Density Parity Check (codes)
LNB Low Noise Block
LP Low Priority
LSB Least Significant Bit
MIS Multiple Input Stream
MPE Multi-Protocol Encapsulation
MPEG Moving Pictures Experts Group
MSB Most Significant Bit
NOTE: In DVB-S2 the MSB is always transmitted first.
NBC Non-Backwards-Compatible
MUX MUltipleX
NA Not Applicable
NP Null Packets
NPD Null-Packet Deletion
OBO Output Back Off
OCT OCTal notation
OMUX Output MUltipleXer - filter
PER (MPEG TS) Packet Error Rate
PID Packet IDentifier
PL Physical Layer
PLL Phase-Locked Loop
PLS Physical Layer Signalling
PRBS Pseudo Random Binary Sequence
PS Professional Services
PSK Phase Shift Keying
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12 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
QEF Quasi-Error-Free
QPSK Quaternary Phase Shift Keying
RF Radio Frequency
RO Roll-Off
SDTV Standard Definition TeleVision
SIS Single Input Stream
SNG Satellite News Gathering
SMATV Satellite Master Antenna TeleVision
SOF Start Of Frame
TDM Time Division Multiplex
TS Transport Stream
TV TeleVision
TWTA Travelling Wave Tube Amplifier
UPL User Packet Length
VCM Variable Coding and Modulation
TSDT Transport Stream Descriptor Table
4 Transmission system description
4.1 System definition
The System is defined as the functional block of equipment performing the adaptation of the baseband digital signals,
from the output of a single (or multiple) MPEG transport stream multiplexer(s) (ISO/IEC 13818-1 [1]), or from the
output of a single (or multiple) generic data source(s), to the satellite channel characteristics. The System is designed to
support source coding as defined in ISO/IEC 13818 [1], TR 101 154 [i.3] and TS 102 005 [i.1]. Data services may be
transported in Transport Stream format according to EN 301 192 [4] (e.g. using Multi-protocol Encapsulation), or
Generic Stream format.
If the received signal is above the C/N+I threshold, the Forward Error Correction (FEC) technique adopted in the
System is designed to provide a "Quasi Error Free" (QEF) quality target. The definition of QEF adopted for DVB-S2 is
"less than one uncorrected error-event per transmission hour at the level of a 5 Mbit/s single TV service decoder",
-7
approximately corresponding to a Transport Stream Packet Error Ratio PER< 10 before de-multiplexer.
4.2 System architecture
According to figure 1, the DVB-S2 System shall be composed of a sequence of functional blocks as described below.
Mode adaptation shall be application dependent. It shall provide input stream interfacing, Input Stream
Synchronization (optional), null-packet deletion (for ACM and Transport Stream input format only), CRC-8 coding for
error detection at packet level in the receiver (for packetized input streams only), merging of input streams (for Multiple
Input Stream modes only) and slicing into DATA FIELDs. For Constant Coding and Modulation (CCM) and single
input Transport Stream, Mode Adaptation shall consist of a "transparent" DVB-ASI (or DVB-parallel) to logical-bit
conversion and CRC-8 coding. For Adaptive Coding and Modulation (ACM), Mode Adaptation shall be according to
annex D.
A Base-Band Header shall be appended in front of the Data Field, to notify the receiver of the input stream format and
Mode Adaptation type. To be noted that the MPEG multiplex transport packets may be asynchronously mapped to the
Base-Band Frames.
For applications requiring sophisticated merging policies, in accordance with specific service requirements (e.g. Quality
of Service), Mode Adaptation may optionally be performed by a separate device, respecting all the rules of the DVB-S2
specification. To allow standard interfacing between Mode and Stream Adaptation functions, an optional modulator
interface (Mode adaptation input interface) is defined, according to clauses I.1 (separate signalling circuit) or I.2
(in-band signalling).
Stream adaptation shall be applied, to provide padding to complete a Base-Band Frame and Base-Band Scrambling.
ETSI
13 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
Forward Error Correction (FEC) Encoding shall be carried out by the concatenation of BCH outer codes and LDPC
(Low Density Parity Check) inner codes (rates 1/4, 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5, 5/6, 8/9, 9/10). Depending on the
application area, the FEC coded block shall have length n = 64 800 bits or 16 200 bits. When VCM and ACM is
ldpc
used, FEC and modulation mode may be changed in different frames, but remains constant within a frame. For
Backwards Compatible modes, the bit-stream at the output of the FEC encoder shall be processed according to annex F.
Bit interleaving shall be applied to FEC coded bits for 8PSK, 16APSK and 32APSK.
Mapping into QPSK, 8PSK, 16APSK and 32APSK constellations shall be applied, depending on the application area.
Gray mapping of constellations shall be used for QPSK and 8PSK.
Physical layer framing shall be applied, synchronous with the FEC frames, to provide Dummy PLFRAME insertion,
Physical Layer (PL) Signalling, pilot symbols insertion (optional) and Physical Layer Scrambling for energy dispersal.
Dummy PLFRAMEs are transmitted when no useful data is ready to be sent on the channel. The System provides a
regular physical layer framing structure, based on SLOTs of M = 90 modulated symbols, allowing reliable receiver
synchronization on the FEC block structure. A slot is devoted to physical layer signalling, including Start-of-Frame
delimitation and transmission mode definition. This mechanism is suitable also for VCM and ACM demodulator
setting. Carrier recovery in the receivers may be facilitated by the introduction of a regular raster of pilot symbols
(P = 36 pilot symbols every 16 SLOTs of 90 symbols), while a pilot-less transmission mode is also available, offering
an additional 2,4 % useful capacity.
Base-Band Filtering and Quadrature Modulation shall be applied, to shape the signal spectrum (squared-root raised
cosine, roll-off factors 0,35 or 0,25 or 0,20) and to generate the RF signal.
MODE ADAPTATION
BB
DATA
Single Signalling
Input Stream
Input Null-packet
Input Dotted sub-systems are
CRC-8
Synchroniser
Buffer
Deletion
Stream interface
Encoder not relevant for
ACM (ACM, TS)
single transport stream
COMMAND
Merger
broadcasting
Slicer
applications
Multiple
Input
Input Stream Null-packet
Input Buffer
CRC-8
Streams Synchroniser Deletion
interface
Encoder
(ACM, TS)
QPSK,
PL Signalling & α=0,35, 0,25,
8PSK,
0,20
Pilot insertion
rates 1/4,1/3,2/5
16APSK,
1/2, 3/5, 2/3, 3/4, 4/5,
32APSK
5/6, 8/9, 9/10
PL
I
Bit
BB Filter
SCRAM
BB mapper
BCH LDPC
Bit
and
Q
PADDER
into BLER
Encoder
SCRAM Encoder
Inter-
Quadrature
constel-
(n ,k )
(n ,k ) ldpc ldpc
bch bch leaver Dummy
Modulation
BLER
Mode
lations
PLFRAME
Adaptation
Insertion
Input
STREAM
Interface
FEC ENCODING MODULATION
PL FRAMING
(optional) ADAPTATION MAPPING
LP stream for
to the RF
BBHEADER
BC modes
satellite
PLFRAME
BBFRAME
FECFRAME
DATAFIELD
channel
Figure 1: Functional block diagram of the DVB-S2 System
4.3 System configurations
Table 1 associates the System configurations to the applications areas. According to table 1, at least "Normative"
subsystems and functionalities shall be implemented in the transmitting and receiving equipment to comply with the
present document Guidelines for mode selection are given in annex H.
ETSI
14 Final draft ETSI EN 302 307 V1.2.1 (2009-04)
Table 1: System configurations and application areas
System configurations Broadcast Interactive DSNG Professional
services services services
QPSK 1/4,1/3, 2/5 O N N N
1/2, 3/5, 2/3, 3/4, 4/5, 5/6,
N N N N
8/9, 9/10
8PSK 3/5, 2/3, 3/4, 5/6, 8/9, 9/10 N N N N
16APSK 2/3, 3/4, 4/5, 5/6, 8/9, 9/10 O N N N
32APSK 3/4, 4/5, 5/6, 8/9, 9/10 O N N N
CCM N N (see note 1) N N
VCM O O O O
ACM NA N (see note 2) O O
FECFRAME (normal) 64 800 (bits) N N N N
FECFRAME (short) 16 200 (bits) NA N O N
Single Transport Stream N N (see note 1) N N
Multiple Transport Streams O O (see note 2) O O
Single Generic Stream NA O (see note 2) NA O
Multiple Generic Streams NA O (see note 2) NA O
Roll-off 0,35, 0,25 and 0,20 N N N N
Input Stream Synchronizer NA except O (see note 3) O (see note 3) O (see note 3)
(see note 3)
Null Packet Deletion NA except O (see note 3) O (see note 3) O (see note 3)
(see note 3)
Dummy Frame insertion NA except N N N
(see note 3)
N = normative, O = optional, NA = not applicable.
NOTE 1: Interactive service receivers shall implement CCM and Single Transport Stream.
NOTE 2: Interactive Service Receivers shall implement ACM at least in one of the two options: Multiple Transport
Streams or Generic Stream (single/multiple input).
NOTE 3: Normative for single/multiple TS input stream(s) combined with ACM/VCM or for multiple TS input streams
combined with CCM.
Within the present document, a number of configurations and mechanisms are defined as "Optional". Configurations
and mechanisms explicitly indicated as "optional" within the present document, for a given application area, need not be
implemented in the equipment to comply with the present document. Nevertheless, when an "optional" mode or
mechanism is implemented, it shall comply with the specification as given in the present document.
5 Subsystems specification
The subsystem specification description is organized according to the functional block diagram of fig
...
European Standard (Telecommunications series)
Digital Video Broadcasting (DVB);
Second generation framing structure, channel coding and
modulation systems for Broadcasting,
Interactive Services, News Gathering and
other broadband satellite applications (DVB-S2)
2 ETSI EN 302 307 V1.2.1 (2009-08)
Reference
REN/JTC-DVB-238
Keywords
BSS, digital, DVB, modulation, satellite, TV
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ETSI
3 ETSI EN 302 307 V1.2.1 (2009-08)
Contents
Intellectual Property Rights . 5
Foreword . 5
1 Scope . 6
2 References . 8
2.1 Normative references . 8
2.2 Informative references . 9
3 Symbols and abbreviations . 9
3.1 Symbols . 9
3.2 Abbreviations . 10
4 Transmission system description . 12
4.1 System definition . 12
4.2 System architecture . 12
4.3 System configurations . 13
5 Subsystems specification . 14
5.1 Mode adaptation . 14
5.1.1 Input interface . 14
5.1.2 Input stream synchronizer (optional, not relevant for single TS - BS) . 15
5.1.3 Null-Packet Deletion (ACM and Transport Stream only) . 15
5.1.4 CRC-8 encoder (for packetized streams only) . 16
5.1.5 Merger/Slicer . 16
5.1.6 Base-Band Header insertion . 17
5.2 Stream adaptation . 19
5.2.1 Padding . 19
5.2.2 BB scrambling . 19
5.3 FEC encoding . 20
5.3.1 Outer encoding (BCH) . 21
5.3.2 Inner encoding (LDPC) . 22
5.3.2.1 Inner coding for normal FECFRAME. 22
5.3.2.2 Inner coding for short FECFRAME . 23
5.3.3 Bit Interleaver (for 8PSK, 16APSK and 32APSK only) . 24
5.4 Bit mapping into constellation. 25
5.4.1 Bit mapping into QPSK constellation . 25
5.4.2 Bit mapping into 8PSK constellation . 26
5.4.3 Bit mapping into 16APSK constellation . 26
5.4.4 Bit mapping into 32APSK . 27
5.5 Physical Layer (PL) framing . 28
5.5.1 Dummy PLFRAME insertion . 29
5.5.2 PL signalling . 29
5.5.2.1 SOF field . 30
5.5.2.2 MODCOD field . 30
5.5.2.3 TYPE field . 30
5.5.2.4 PLS code . 30
5.5.3 Pilots insertion . 31
5.5.4 Physical layer scrambling . 31
5.6 Baseband shaping and quadrature modulation . 33
6 Error performance . 34
Annex A (normative): Signal spectrum at the modulator output . 35
Annex B (normative): Addresses of parity bit accumulators for n = 64 800 . 37
ldpc
Annex C (normative): Addresses of parity bit accumulators for n = 16 200 . 47
ldpc
ETSI
4 ETSI EN 302 307 V1.2.1 (2009-08)
Annex D (normative): Additional Mode Adaptation and ACM tools . 50
D.1 "ACM Command" signalling interface . 50
D.2 Input stream synchronizer . 50
D.3 Null-packet Deletion (normative for input transport streams and ACM). 52
D.4 BBHEADER and Merging/slicing Policy for various application areas . 53
D.5 Signalling of reception quality via return channel (Normative for ACM) . 54
Annex E (normative): SI and signal identification for DSNG and contribution applications . 56
Annex F (normative): Backwards Compatible modes (optional) . 57
Annex G (informative): Supplementary information on receiver implementation . 60
G.1 Carrier recovery . 60
G.2 FEC decoding . 60
G.3 ACM: Transport Stream regeneration and clock recovery using ISCR . 63
G.4 Non linearity pre-compensation and Intersymbol Interference suppression techniques . 63
G.5 Interactive services using DVB-RCS return link: user terminal synchronization . 64
Annex H (informative): Examples of possible use of the System . 65
H.1 CCM digital TV broadcasting: bit rate capacity and C/N requirements . 65
H.2 Distribution of multiple TS multiplexes to DTT Transmitters (Multiple TS, CCM) . 67
H.3 SDTV and HDTV broadcasting with differentiated protection (VCM, Multiple TS) . 68
H.4 DSNG Services using ACM (Single transport Stream, information rate varying in time) . 68
H.5 IP Unicast Services (Non-uniform protection on a user-by-user basis) . 69
H.6 Example performance of BC modes. 71
H.7 Satellite transponder models for simulations . 72
H.8 Phase noise masks for simulations . 74
Annex I (normative): Mode Adaptation input interfaces (optional) . 75
I.1 Mode Adaptation input interface with separate signalling circuit (optional) . 75
I.2 Mode Adaptation input interface with in-band signalling (optional) . 76
Annex J (informative): Bibliography . 77
History . 78
ETSI
5 ETSI EN 302 307 V1.2.1 (2009-08)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This European Standard (Telecommunications series) has been produced by Joint Technical Committee (JTC)
Broadcast of the European Broadcasting Union (EBU), Comité Européen de Normalisation ELECtrotechnique
(CENELEC) and the European Telecommunications Standards Institute (ETSI).
The work of the JTC was based on the studies carried out by the European DVB Project under the auspices of
theAd Hoc Group on DVB-S2 of the DVB Technical Module. This joint group of industry, operators and broadcasters
provided the necessary information on all relevant technical matters (see bibliography).
NOTE: The EBU/ETSI JTC Broadcast was established in 1990 to co-ordinate the drafting of standards in the
specific field of broadcasting and related fields. Since 1995 the JTC Broadcast became a tripartite body
by including in the Memorandum of Understanding also CENELEC, which is responsible for the
standardization of radio and television receivers. The EBU is a professional association of broadcasting
organizations whose work includes the co-ordination of its members' activities in the technical, legal,
programme-making and programme-exchange domains. The EBU has active members in about
60 countries in the European broadcasting area; its headquarters is in Geneva.
European Broadcasting Union
CH-1218 GRAND SACONNEX (Geneva)
Switzerland
Tel: +41 22 717 21 11
Fax: +41 22 717 24 81
Founded in September 1993, the DVB Project is a market-led consortium of public and private sector organizations in
the television industry. Its aim is to establish the framework for the introduction of MPEG-2 based digital television
services. Now comprising over 200 organizations from more than 25 countries around the world, DVB fosters
market-led systems, which meet the real needs, and economic circumstances, of the consumer electronics and the
broadcast industry.
National transposition dates
Date of adoption of this EN: 24 August 2009
Date of latest announcement of this EN (doa): 30 November 2009
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 31 May 2010
Date of withdrawal of any conflicting National Standard (dow): 31 May 2010
ETSI
6 ETSI EN 302 307 V1.2.1 (2009-08)
1 Scope
DVB-S (EN 300 421 [2]) was introduced as a standard in 1994 and DVB-DSNG (EN 301 210 [3]) in 1997. The DVB-S
standard specifies QPSK modulation and concatenated convolutional and Reed-Solomon channel coding, and is now
used by most satellite operators worldwide for television and data broadcasting services. DVB-DSNG specifies, in
addition to DVB-S format, the use of 8PSK and 16QAM modulation for satellite news gathering and contribution
services.
Since 1997, digital satellite transmission technology has evolved somewhat:
• New channel coding schemes, combined with higher order modulation, promise more powerful alternatives to
the DVB-S/DVB-DSNG coding and modulation schemes. The result is a capacity gain in the order of 30 % at
a given transponder bandwidth and transmitted EIRP, depending on the modulation type and code rate.
• Variable Coding and Modulation (VCM) may be applied to provide different levels of error protection to
different service components (e.g. SDTV and HDTV, audio, multimedia).
• In the case of interactive and point-to-point applications, the VCM functionality may be combined with the use
of return channels, to achieve Adaptive Coding and Modulation (ACM). This technique provides more exact
channel protection and dynamic link adaptation to propagation conditions, targeting each individual receiving
terminal. ACM systems promise satellite capacity gains of up to 100 % - 200 %. In addition, service
availability may be extended compared to a constant protection system (CCM) such as DVB-S or
DVB-DSNG. Such gains are achieved by informing the satellite up-link station of the channel condition
(e.g. C/N+I) of each receiving terminal via the satellite or terrestrial return channels.
• DVB-S and DVB-DSNG are strictly focused on a unique data format, the MPEG Transport Stream
(ISO/IEC 13818-1 [1] or a reference to it). Extended flexibility to cope with other input data formats (such as
multiple Transport Streams, or generic data formats) is now possible without significant complexity increase.
The present document defines a "second generation" modulation and channel coding system (denoted the "System" or
"DVB-S2" for the purposes of the present document) to make use of the improvements listed above. DVB-S2 is a
single, very flexible standard, covering a variety of applications by satellite, as described below. It is characterized by:
• a flexible input stream adapter, suitable for operation with single and multiple input streams of various formats
(packetized or continuous);
• a powerful FEC system based on LDPC (Low-Density Parity Check) codes concatenated with BCH codes,
allowing Quasi-Error-Free operation at about 0,7 dB to 1 dB from the Shannon limit, depending on the
transmission mode (AWGN channel, modulation constrained Shannon limit);
• a wide range of code rates (from 1/4 up to 9/10); 4 constellations, ranging in spectrum efficiency from
2 bit/s/Hz to 5 bit/s/Hz, optimized for operation over non-linear transponders;
• a set of three spectrum shapes with roll-off factors 0,35, 0,25 and 0,20;
• Adaptive Coding and Modulation (ACM) functionality, optimizing channel coding and modulation on a
frame-by-frame basis.
The System has been optimized for the following broadband satellite applications:
Broadcast Services (BS) Digital multi-programme Television (TV)/High Definition Television (HDTV)
Broadcasting services to be used for primary and secondary distribution in the Fixed Satellite Service (FSS) and the
Broadcast Satellite Service (BSS) bands.
ETSI
7 ETSI EN 302 307 V1.2.1 (2009-08)
DVB-S2 is intended to provide Direct-To-Home (DTH) services for consumer Integrated Receiver Decoder (IRD), as
well as collective antenna systems (Satellite Master Antenna Television - SMATV) and cable television head-end
stations (possibly with remodulation, see EN 300 429 [5]). DVB-S2 may be considered a successor to the current
DVB-S standard EN 300 421 [2], and may be introduced for new services and allow for a long-term migration. BS
services are transported in MPEG Transport Stream format. VCM may be applied on multiple transport stream to
achieve a differentiated error protection for different services (TV, HDTV, audio, multimedia). Two modes are
available:
• NBC-BS (Non Backwards Compatible Broadcast Services) is not backwards-compatible with EN 300 421 [2].
• BC-BS (Backwards-Compatible Broadcast Services) is backwards-compatible to EN 300 421 [2]
(see annex F).
In fact, with a large number of DVB-S receivers already installed, backwards compatibility may be required for a period
of time, where old receivers continue to receive the same capacity as before, while the new DVB-S2 receivers could
receive additional capacity broadcasts. When the complete receiver population has migrated to DVB-S2, the transmitted
signal can be modified to a non-backward compatible mode, thus exploiting the full potential of DVB-S2. To facilitate
the reception of DVB-S services by DVB-S2 receivers, implementation of DVB-S in DVB-S2 chips is highly
recommended.
Interactive Services (IS) Interactive data services including Internet access
DVB-S2 is intended to provide interactive services to consumer IRDs and to personal computers, where DVB-S2's
forward path supersedes the current DVB-S standard EN 300 421 [2] for interactive systems. The return path can be
implemented using various DVB interactive systems, such as DVB-RCS (EN 301 790 [6]), DVB-RCP
(ETS 300 801 [7]), DVB-RCG (EN 301 195 [8]), DVB-RCC (ES 200 800 [9]). Data services are transported in (single
or multiple) Transport Stream format according to EN 301 192 [4] (e.g. using Multiprotocol Encapsulation), or in
(single or multiple) generic stream format. DVB-S2 can provide Constant Coding and Modulation (CCM), or Adaptive
Coding and Modulation (ACM), where each individual satellite receiving station controls the protection mode of the
traffic addressed to it. Input Stream Adaptation for ACM is specified in annex D.
Digital TV Contribution and Satellite News Gathering (DTVC/DSNG)
Digital television contribution applications by satellite consist of point-to-point or point-to-multipoint transmissions,
connecting fixed or transportable uplink and receiving stations. They are not intended for reception by the general
public. According to ITU-R Recommendation SNG.770-1 [10], SNG is defined as "Temporary and occasional
transmission with short notice of television or sound for broadcasting purposes, using highly portable or transportable
uplink earth stations .". Services are transported in single (or multiple) MPEG Transport Stream format. DVB-S2 can
provide Constant Coding and Modulation (CCM), or Adaptive Coding and Modulation (ACM). In this latter case, a
single satellite receiving station typically controls the protection mode of the full multiplex. Input Stream Adaptation for
ACM is specified in annex D.
Data content distribution/trunking and other professional applications (PS)
These services are mainly point-to-point or point-to-multipoint, including interactive services to professional head-ends,
which re-distribute services over other media. Services may be transported in (single or multiple) generic stream format.
The system can provide Constant Coding and Modulation (CCM), Variable Coding and Modulation (VCM) or
Adaptive Coding and Modulation (ACM). In this latter case, a single satellite receiving station typically controls the
protection mode of the full TDM multiplex, or multiple receiving stations control the protection mode of the traffic
addressed to each one. In either case, interactive or non-interactive, the present document is only concerned with the
forward broadband channel.
DVB-S2 is suitable for use on different satellite transponder bandwidths and frequency bands. The symbol rate is
matched to given transponder characteristics, and, in the case of multiple carriers per transponder (FDM), to the
frequency plan adopted. Examples of possible DVB-S2 use are given in clause H.1.
Digital transmissions via satellite are affected by power and bandwidth limitations. Therefore DVB-S2 provides for
many transmission modes (FEC coding and modulations), giving different trade-offs between power and spectrum
efficiency (see clause H.1). For some specific applications (e.g. broadcasting) modes such as QPSK and 8PSK, with
their quasi-constant envelope, are appropriate for operation with saturated satellite power amplifiers (in single carrier
per transponder configuration). When higher power margins are available, spectrum efficiency can be further increased
to reduce bit delivery cost. In these cases also 16APSK and 32APSK can operate in single carrier mode close to the
satellite HPA saturation by pre-distortion techniques. All the modes are appropriate for operation in quasi-linear
satellite channels, in multi-carrier Frequency Division Multiplex (FDM) type applications.
ETSI
8 ETSI EN 302 307 V1.2.1 (2009-08)
DVB-S2 is compatible with Moving Pictures Experts Group (MPEG-2 and MPEG-4) coded TV services (see
ISO/IEC 13818-1 [1]), with a Transport Stream packet multiplex. Multiplex flexibility allows the use of the
transmission capacity for a variety of TV service configurations, including sound and data services. All service
components are Time Division Multiplexed (TDM) on a single digital carrier.
The present document:
• gives a general description of the DVB-S2 system;
• specifies the digitally modulated signal in order to allow compatibility between pieces of equipment developed
by different manufacturers. This is achieved by describing in detail the signal processing principles at the
modulator side, while the processing at the receive side is left open to different implementation solutions.
However, it is necessary in the present document to refer to certain aspects of reception;
• identifies the global performance requirements and features of the System, in order to meet the service quality
targets.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• Non-specific reference may be made only to a complete document or a part thereof and only in the following
cases:
- if it is accepted that it will be possible to use all future changes of the referenced document for the
purposes of the referring document;
- for informative references.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated
references, only the edition cited applies. For non-specific references, the latest edition of the referenced document
(including any amendments) applies.
[1] ISO/IEC 13818 (parts 1 and 2): "Information technology - Generic coding of moving pictures and
associated audio information".
[2] ETSI EN 300 421 (V.1.1.2): "Digital Video Broadcasting (DVB); Framing structure, channel
coding and modulation for 11/12 GHz satellite services".
[3] ETSI EN 301 210: "Digital Video Broadcasting (DVB); Framing structure, channel coding and
modulation for Digital Satellite News Gathering (DSNG) and other contribution applications by
satellite".
[4] ETSI EN 301 192: "Digital Video Broadcasting (DVB); DVB specification for data broadcasting".
[5] ETSI EN 300 429: "Digital Video Broadcasting (DVB); Framing structure, channel coding and
modulation for cable systems".
[6] ETSI EN 301 790: "Digital Video Broadcasting (DVB); Interaction channel for satellite
distribution systems".
ETSI
9 ETSI EN 302 307 V1.2.1 (2009-08)
[7] ETSI ETS 300 801: "Digital Video Broadcasting (DVB); Interaction channel through Public
Switched Telecommunications Network (PSTN)/ Integrated Services Digital Networks (ISDN)".
[8] ETSI EN 301 195: "Digital Video Broadcasting (DVB); Interaction channel through the Global
System for Mobile communications (GSM)".
[9] ETSI ES 200 800: "Digital Video Broadcasting (DVB); DVB interaction channel for Cable TV
distribution systems (CATV)".
[10] ITU-R Recommendation SNG.770-1: "Uniform operational procedures for satellite news gathering
(SNG)".
[11] ETSI ETS 300 802: "Digital Video Broadcasting (DVB); Network-independent protocols for DVB
interactive services".
2.2 Informative references
The following referenced documents are not essential to the use of the present document but they assist the user with
regard to a particular subject area. For non-specific references, the latest version of the referenced document (including
any amendments) applies.
[i.1] ETSI TS 102 005: "Digital Video Broadcasting (DVB); Specification for the use of Video and
Audio Coding in DVB services delivered directly over IP protocols".
[i.2] ETSI EN 300 744: "Digital Video Broadcasting (DVB); Framing structure, channel coding and
modulation for digital terrestrial television".
[i.3] ETSI TR 101 154: "Digital Video Broadcasting (DVB); Implementation guidelines for the use of
MPEG-2 Systems, Video and Audio in satellite, cable and terrestrial broadcasting applications".
[i.4] ETSI TR 101 162: "Digital Video Broadcasting (DVB); Allocation of Service Information (SI)
codes for DVB systems".
3 Symbols and abbreviations
3.1 Symbols
For the purposes of the present document, the following symbols apply:
α Roll-off factor
γ Ratio between constellation radii for 16APSK and 32APSK
c codeword
C/N Carrier-to-noise power ratio (N measured in a bandwidth equal to symbol rate)
C/N+I Carrier-to-(Noise+Interference) ratio
d ,d ,., d ,d
n −k −1 n −k −2 1 0
bch bch bch bch
BCH code redundancy bits
d(x) BCH code remainder of the division between the generator polynomial and
n −k
bch bch
x
m(x)
DFL Data Field Length
dmin LDPC code minimum distance
E /N Ratio between the energy per information bit and single sided noise power
b 0
spectral density
E /N Ratio between the energy per transmitted symbol and single sided noise power
s 0
spectral density
f Nyquist frequency
N
f Carrier frequency
G PLS code generator matrix
g(x) code generator polynomial
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10 ETSI EN 302 307 V1.2.1 (2009-08)
g (x), g (x), …, g (x) polynomials to obtain BCH code generator polynomial
1 2 12
i LDPC code information block
i ,i ,.,i LDPC code information bits
0 1 k −1
ldpc
H(f) RC filters frequency transfer function
H LDPC code parity check matrix
(n-k)xn
I, Q In-phase, Quadrature phase components of the modulated signal
K number of bits of BCH uncoded Block
bch
N number of bits of BCH coded Block
bch
k number of bits of LDPC uncoded Block
ldpc
n number of bits of LDPC coded Block
ldpc
η PLFRAMING efficiency
η code efficiency
c
η number of transmitted bits per constellation symbol
MOD
η System spectral efficiency
tot
m BCH code information word
m(x) BCH code message polynomial
m , m ,.,m , m BCH code information bits
k −1 k −2 1 0
bch bch
M number of modulated symbols in SLOT
p , p ,.p LDPC code parity bits
0 1 n −k −1
ldpc ldpc
P number of pilot symbols in a pilot block
q code rate dependant constant for LDPC codes
θ deviation angle in hierarchical constellations
r In-band ripple (dB)
m
R Symbol rate corresponding to the bilateral Nyquist bandwidth of the
s
modulated signal
R Useful bit rate at the DVB-S2 system input
u
S Number of Slots in a XFECFRAME
T Symbol period
s
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
8PSK 8-ary Phase Shift Keying
16APSK 16-ary Amplitude and Phase Shift Keying
32APSK 32-ary Amplitude and Phase Shift Keying
ACM Adaptive Coding and Modulation
ASI Asynchronous Serial Interface
AWGN Additive White Gaussian Noise
BB BaseBand
BC Backwards-Compatible
NOTE: Referred to the system allowing partial stream reception by DVB-S receivers.
BCH Bose-Chaudhuri-Hocquenghem multiple error correction binary block code
BER Bit Error Ratio
B Bandwidth of the frequency Slot allocated to a service
S
BS Broadcast Service
BSS Broadcast Satellite Service
BW BandWidth (at -3 dB) of the transponder
CBR Constant Bit Rate
CCM Constant Coding and Modulation
CNI Carrier to Noise plus Interference ratio
CRC Cyclic Redundancy Check
D Decimal notation
DD Decision Directed
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11 ETSI EN 302 307 V1.2.1 (2009-08)
DEMUX DEMUltipleXer
DF Data Field
DNP Deleted Null Packets
DSNG Digital Satellite News Gathering
DTH Direct To Home
DTT Digital Terrestrial Television
DVB Digital Video Broadcasting project
DVB-S DVB System for satellite broadcasting
NOTE: As specified in EN 300 421 [2].
DVB-S2 second generation DVB System for satellite broadcasting and unicasting
NOTE: As specified in the present document.
EBU European Broadcasting Union
EN European Norm
FDM Frequency Division Multiplex
FEC Forward Error Correction
FIFO First In First Out
FSS Fixed Satellite Service
GF Galois Field
GS Generic Stream
HDTV High Definition TeleVision
HEX HEXadecimal notation
HP High Priority
IBO Input Back Off
IF Intermediate Frequency
IMUX Input MUltipleXer - filter
IRD Integrated Receiver Decoder
IS Interactive Services
ISCR Input Stream Clock Reference
ISI Input Stream Identifier
ISSY Input Stream SYnchronizer
ISSYI Input Stream SYnchronizer Indicator
ITU International Telecommunications Union
LDPC Low Density Parity Check (codes)
LNB Low Noise Block
LP Low Priority
LSB Least Significant Bit
MIS Multiple Input Stream
MPE Multi-Protocol Encapsulation
MPEG Moving Pictures Experts Group
MSB Most Significant Bit
NOTE: In DVB-S2 the MSB is always transmitted first.
NBC Non-Backwards-Compatible
MUX MUltipleX
NA Not Applicable
NP Null Packets
NPD Null-Packet Deletion
OBO Output Back Off
OCT OCTal notation
OMUX Output MUltipleXer - filter
PER (MPEG TS) Packet Error Rate
PID Packet IDentifier
PL Physical Layer
PLL Phase-Locked Loop
PLS Physical Layer Signalling
PRBS Pseudo Random Binary Sequence
PS Professional Services
PSK Phase Shift Keying
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12 ETSI EN 302 307 V1.2.1 (2009-08)
QEF Quasi-Error-Free
QPSK Quaternary Phase Shift Keying
RF Radio Frequency
RO Roll-Off
SDTV Standard Definition TeleVision
SIS Single Input Stream
SNG Satellite News Gathering
SMATV Satellite Master Antenna TeleVision
SOF Start Of Frame
TDM Time Division Multiplex
TS Transport Stream
TV TeleVision
TWTA Travelling Wave Tube Amplifier
UPL User Packet Length
VCM Variable Coding and Modulation
TSDT Transport Stream Descriptor Table
4 Transmission system description
4.1 System definition
The System is defined as the functional block of equipment performing the adaptation of the baseband digital signals,
from the output of a single (or multiple) MPEG transport stream multiplexer(s) (ISO/IEC 13818-1 [1]), or from the
output of a single (or multiple) generic data source(s), to the satellite channel characteristics. The System is designed to
support source coding as defined in ISO/IEC 13818 [1], TR 101 154 [i.3] and TS 102 005 [i.1]. Data services may be
transported in Transport Stream format according to EN 301 192 [4] (e.g. using Multi-protocol Encapsulation), or
Generic Stream format.
If the received signal is above the C/N+I threshold, the Forward Error Correction (FEC) technique adopted in the
System is designed to provide a "Quasi Error Free" (QEF) quality target. The definition of QEF adopted for DVB-S2 is
"less than one uncorrected error-event per transmission hour at the level of a 5 Mbit/s single TV service decoder",
-7
approximately corresponding to a Transport Stream Packet Error Ratio PER< 10 before de-multiplexer.
4.2 System architecture
According to figure 1, the DVB-S2 System shall be composed of a sequence of functional blocks as described below.
Mode adaptation shall be application dependent. It shall provide input stream interfacing, Input Stream
Synchronization (optional), null-packet deletion (for ACM and Transport Stream input format only), CRC-8 coding for
error detection at packet level in the receiver (for packetized input streams only), merging of input streams (for Multiple
Input Stream modes only) and slicing into DATA FIELDs. For Constant Coding and Modulation (CCM) and single
input Transport Stream, Mode Adaptation shall consist of a "transparent" DVB-ASI (or DVB-parallel) to logical-bit
conversion and CRC-8 coding. For Adaptive Coding and Modulation (ACM), Mode Adaptation shall be according to
annex D.
A Base-Band Header shall be appended in front of the Data Field, to notify the receiver of the input stream format and
Mode Adaptation type. To be noted that the MPEG multiplex transport packets may be asynchronously mapped to the
Base-Band Frames.
For applications requiring sophisticated merging policies, in accordance with specific service requirements (e.g. Quality
of Service), Mode Adaptation may optionally be performed by a separate device, respecting all the rules of the DVB-S2
specification. To allow standard interfacing between Mode and Stream Adaptation functions, an optional modulator
interface (Mode adaptation input interface) is defined, according to clauses I.1 (separate signalling circuit) or I.2
(in-band signalling).
Stream adaptation shall be applied, to provide padding to complete a Base-Band Frame and Base-Band Scrambling.
ETSI
13 ETSI EN 302 307 V1.2.1 (2009-08)
Forward Error Correction (FEC) Encoding shall be carried out by the concatenation of BCH outer codes and LDPC
(Low Density Parity Check) inner codes (rates 1/4, 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5, 5/6, 8/9, 9/10). Depending on the
application area, the FEC coded block shall have length n = 64 800 bits or 16 200 bits. When VCM and ACM is
ldpc
used, FEC and modulation mode may be changed in different frames, but remains constant within a frame. For
Backwards Compatible modes, the bit-stream at the output of the FEC encoder shall be processed according to annex F.
Bit interleaving shall be applied to FEC coded bits for 8PSK, 16APSK and 32APSK.
Mapping into QPSK, 8PSK, 16APSK and 32APSK constellations shall be applied, depending on the application area.
Gray mapping of constellations shall be used for QPSK and 8PSK.
Physical layer framing shall be applied, synchronous with the FEC frames, to provide Dummy PLFRAME insertion,
Physical Layer (PL) Signalling, pilot symbols insertion (optional) and Physical Layer Scrambling for energy dispersal.
Dummy PLFRAMEs are transmitted when no useful data is ready to be sent on the channel. The System provides a
regular physical layer framing structure, based on SLOTs of M = 90 modulated symbols, allowing reliable receiver
synchronization on the FEC block structure. A slot is devoted to physical layer signalling, including Start-of-Frame
delimitation and transmission mode definition. This mechanism is suitable also for VCM and ACM demodulator
setting. Carrier recovery in the receivers may be facilitated by the introduction of a regular raster of pilot symbols
(P = 36 pilot symbols every 16 SLOTs of 90 symbols), while a pilot-less transmission mode is also available, offering
an additional 2,4 % useful capacity.
Base-Band Filtering and Quadrature Modulation shall be applied, to shape the signal spectrum (squared-root raised
cosine, roll-off factors 0,35 or 0,25 or 0,20) and to generate the RF signal.
MODE ADAPTATION
BB
DATA
Single Signalling
Input Stream
Input Null-packet
Input Dotted sub-systems are
CRC-8
Synchroniser
Buffer
Deletion
Stream interface
Encoder not relevant for
ACM (ACM, TS)
single transport stream
COMMAND
Merger
broadcasting
Slicer
applications
Multiple
Input
Input Stream Null-packet
Input Buffer
CRC-8
Streams Synchroniser Deletion
interface
Encoder
(ACM, TS)
QPSK,
PL Signalling & α=0,35, 0,25,
8PSK,
0,20
Pilot insertion
rates 1/4,1/3,2/5
16APSK,
1/2, 3/5, 2/3, 3/4, 4/5,
32APSK
5/6, 8/9, 9/10
PL
I
Bit
BB Filter
SCRAM
BB mapper
BCH LDPC
Bit
and
Q
PADDER
into BLER
Encoder
SCRAM Encoder
Inter-
Quadrature
constel-
(n ,k )
(n ,k ) ldpc ldpc
bch bch leaver Dummy
Modulation
BLER
Mode
lations
PLFRAME
Adaptation
Insertion
Input
STREAM
Interface
FEC ENCODING MODULATION
PL FRAMING
(optional) ADAPTATION MAPPING
LP stream for
to the RF
BBHEADER
BC modes
satellite
PLFRAME
BBFRAME
FECFRAME
DATAFIELD
channel
Figure 1: Functional block diagram of the DVB-S2 System
4.3 System configurations
Table 1 associates the System configurations to the applications areas. According to table 1, at least "Normative"
subsystems and functionalities shall be implemented in the transmitting and receiving equipment to comply with the
present document Guidelines for mode selection are given in annex H.
ETSI
14 ETSI EN 302 307 V1.2.1 (2009-08)
Table 1: System configurations and application areas
System configurations Broadcast Interactive DSNG Professional
services services services
QPSK 1/4,1/3, 2/5 O N N N
1/2, 3/5, 2/3, 3/4, 4/5, 5/6,
N N N N
8/9, 9/10
8PSK 3/5, 2/3, 3/4, 5/6, 8/9, 9/10 N N N N
16APSK 2/3, 3/4, 4/5, 5/6, 8/9, 9/10 O N N N
32APSK 3/4, 4/5, 5/6, 8/9, 9/10 O N N N
CCM N N (see note 1) N N
VCM O O O O
ACM NA N (see note 2) O O
FECFRAME (normal) 64 800 (bits) N N N N
FECFRAME (short) 16 200 (bits) NA N O N
Single Transport Stream N N (see note 1) N N
Multiple Transport Streams O O (see note 2) O O
Single Generic Stream NA O (see note 2) NA O
Multiple Generic Streams NA O (see note 2) NA O
Roll-off 0,35, 0,25 and 0,20 N N N N
Input Stream Synchronizer NA except O (see note 3) O (see note 3) O (see note 3)
(see note 3)
Null Packet Deletion NA except O (see note 3) O (see note 3) O (see note 3)
(see note 3)
Dummy Frame insertion NA except N N N
(see note 3)
N = normative, O = optional, NA = not applicable.
NOTE 1: Interactive service receivers shall implement CCM and Single Transport Stream.
NOTE 2: Interactive Service Receivers shall implement ACM at least in one of the two options: Multiple Transport
Streams or Generic Stream (single/multiple input).
NOTE 3: Normative for single/multiple TS input stream(s) combined with ACM/VCM or for multiple TS input streams
combined with CCM.
Within the present document, a number of configurations and mechanisms are defined as "Optional". Configurations
and mechanisms explicitly indicated as "optional" within the present document, for a given application area, need not be
implemented in the equipment to comply with the present document. Nevertheless, when an "optional" mode or
mechanism is implemented, it shall comply with the specification as given in the present document.
5 Subsystems specification
The subsystem specification description is organized according to the functional block diagram of figure 1.
5.1 Mode adaptation
This sub-system shall perform Input Interfacing, Input Stream Synchronization (optional), Null-packet deletion (for TS
input streams and ACM only), CRC-8 encodin
...
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Digitalna videoradiodifuzija (DVB) - Druga generacija strukture okvirov, kodiranja kanalov in modulacijskih sistemov za radiodifuzijo, interaktivne storitve, novinarstvo in druge širokopasovne satelitske aplikacijeDigital Video Broadcasting (DVB) - Second generation framing structure, channel coding and modulation systems for Broadcasting, Interactive Services, News Gathering and other broadband satellite applications (DVB-S2)33.170Televizijska in radijska difuzijaTelevision and radio broadcastingICS:Ta slovenski standard je istoveten z:EN 302 307 Version 1.2.1SIST EN 302 307 V1.2.1:2009en01-november-2009SIST EN 302 307 V1.2.1:2009SLOVENSKI
STANDARD
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 2
Reference REN/JTC-DVB-238 Keywords BSS, digital, DVB, modulation, satellite, TV ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE
Tel.: +33 4 92 94 42 00
Fax: +33 4 93 65 47 16
Siret N° 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88
Important notice Individual copies of the present document can be downloaded from: http://www.etsi.org The present document may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive within ETSI Secretariat. Users of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http://portal.etsi.org/tb/status/status.asp If you find errors in the present document, please send your comment to one of the following services: http://portal.etsi.org/chaircor/ETSI_support.asp Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 2009. © European Broadcasting Union 2009. All rights reserved.
DECTTM, PLUGTESTSTM, UMTSTM, TIPHONTM, the TIPHON logo and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members. 3GPPTM is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners. LTE™ is a Trade Mark of ETSI currently being registered for the benefit of its Members and of the 3GPP Organizational Partners. GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association. SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 3 Contents Intellectual Property Rights . 5 Foreword . 5 1 Scope . 6 2 References . 8 2.1 Normative references . 8 2.2 Informative references . 9 3 Symbols and abbreviations . 9 3.1 Symbols . 9 3.2 Abbreviations . 10 4 Transmission system description . 12 4.1 System definition . 12 4.2 System architecture . 12 4.3 System configurations . 13 5 Subsystems specification . 14 5.1 Mode adaptation . 14 5.1.1 Input interface . 14 5.1.2 Input stream synchronizer (optional, not relevant for single TS - BS) . 15 5.1.3 Null-Packet Deletion (ACM and Transport Stream only) . 15 5.1.4 CRC-8 encoder (for packetized streams only) . 16 5.1.5 Merger/Slicer . 16 5.1.6 Base-Band Header insertion . 17 5.2 Stream adaptation . 19 5.2.1 Padding . 19 5.2.2 BB scrambling . 19 5.3 FEC encoding . 20 5.3.1 Outer encoding (BCH) . 21 5.3.2 Inner encoding (LDPC) . 22 5.3.2.1 Inner coding for normal FECFRAME. 22 5.3.2.2 Inner coding for short FECFRAME . 23 5.3.3 Bit Interleaver (for 8PSK, 16APSK and 32APSK only) . 24 5.4 Bit mapping into constellation. 25 5.4.1 Bit mapping into QPSK constellation . 25 5.4.2 Bit mapping into 8PSK constellation . 26 5.4.3 Bit mapping into 16APSK constellation . 26 5.4.4 Bit mapping into 32APSK . 27 5.5 Physical Layer (PL) framing . 28 5.5.1 Dummy PLFRAME insertion . 29 5.5.2 PL signalling . 29 5.5.2.1 SOF field . 30 5.5.2.2 MODCOD field . 30 5.5.2.3 TYPE field . 30 5.5.2.4 PLS code . 30 5.5.3 Pilots insertion . 31 5.5.4 Physical layer scrambling . 31 5.6 Baseband shaping and quadrature modulation . 33 6 Error performance . 34 Annex A (normative): Signal spectrum at the modulator output . 35 Annex B (normative): Addresses of parity bit accumulators for nldpc = 64 800 . 37 Annex C (normative): Addresses of parity bit accumulators for nldpc = 16 200 . 47 SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 4 Annex D (normative): Additional Mode Adaptation and ACM tools . 50 D.1 "ACM Command" signalling interface . 50 D.2 Input stream synchronizer . 50 D.3 Null-packet Deletion (normative for input transport streams and ACM). 52 D.4 BBHEADER and Merging/slicing Policy for various application areas . 53 D.5 Signalling of reception quality via return channel (Normative for ACM) . 54 Annex E (normative): SI and signal identification for DSNG and contribution applications . 56 Annex F (normative): Backwards Compatible modes (optional) . 57 Annex G (informative): Supplementary information on receiver implementation . 60 G.1 Carrier recovery . 60 G.2 FEC decoding . 60 G.3 ACM: Transport Stream regeneration and clock recovery using ISCR . 63 G.4 Non linearity pre-compensation and Intersymbol Interference suppression techniques . 63 G.5 Interactive services using DVB-RCS return link: user terminal synchronization . 64 Annex H (informative): Examples of possible use of the System . 65 H.1 CCM digital TV broadcasting: bit rate capacity and C/N requirements . 65 H.2 Distribution of multiple TS multiplexes to DTT Transmitters (Multiple TS, CCM) . 67 H.3 SDTV and HDTV broadcasting with differentiated protection (VCM, Multiple TS) . 68 H.4 DSNG Services using ACM (Single transport Stream, information rate varying in time) . 68 H.5 IP Unicast Services (Non-uniform protection on a user-by-user basis) . 69 H.6 Example performance of BC modes. 71 H.7 Satellite transponder models for simulations . 72 H.8 Phase noise masks for simulations . 74 Annex I (normative): Mode Adaptation input interfaces (optional) . 75 I.1 Mode Adaptation input interface with separate signalling circuit (optional) . 75 I.2 Mode Adaptation input interface with in-band signalling (optional) . 76 Annex J (informative): Bibliography . 77 History . 78
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 5 Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to ETSI. The information pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web server (http://webapp.etsi.org/IPR/home.asp). Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web server) which are, or may be, or may become, essential to the present document. Foreword This European Standard (Telecommunications series) has been produced by Joint Technical Committee (JTC) Broadcast of the European Broadcasting Union (EBU), Comité Européen de Normalisation ELECtrotechnique (CENELEC) and the European Telecommunications Standards Institute (ETSI). The work of the JTC was based on the studies carried out by the European DVB Project under the auspices of theAd Hoc Group on DVB-S2 of the DVB Technical Module. This joint group of industry, operators and broadcasters provided the necessary information on all relevant technical matters (see bibliography). NOTE: The EBU/ETSI JTC Broadcast was established in 1990 to co-ordinate the drafting of standards in the specific field of broadcasting and related fields. Since 1995 the JTC Broadcast became a tripartite body by including in the Memorandum of Understanding also CENELEC, which is responsible for the standardization of radio and television receivers. The EBU is a professional association of broadcasting organizations whose work includes the co-ordination of its members' activities in the technical, legal, programme-making and programme-exchange domains. The EBU has active members in about 60 countries in the European broadcasting area; its headquarters is in Geneva. European Broadcasting Union CH-1218 GRAND SACONNEX (Geneva) Switzerland Tel: +41 22 717 21 11 Fax: +41 22 717 24 81
Founded in September 1993, the DVB Project is a market-led consortium of public and private sector organizations in the television industry. Its aim is to establish the framework for the introduction of MPEG-2 based digital television services. Now comprising over 200 organizations from more than 25 countries around the world, DVB fosters
market-led systems, which meet the real needs, and economic circumstances, of the consumer electronics and the broadcast industry.
National transposition dates Date of adoption of this EN: 24 August 2009 Date of latest announcement of this EN (doa): 30 November 2009 Date of latest publication of new National Standard or endorsement of this EN (dop/e):
31 May 2010 Date of withdrawal of any conflicting National Standard (dow): 31 May 2010
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 6 1 Scope DVB-S (EN 300 421 [2]) was introduced as a standard in 1994 and DVB-DSNG (EN 301 210 [3]) in 1997. The DVB-S standard specifies QPSK modulation and concatenated convolutional and Reed-Solomon channel coding, and is now used by most satellite operators worldwide for television and data broadcasting services. DVB-DSNG specifies, in addition to DVB-S format, the use of 8PSK and 16QAM modulation for satellite news gathering and contribution services. Since 1997, digital satellite transmission technology has evolved somewhat: • New channel coding schemes, combined with higher order modulation, promise more powerful alternatives to the DVB-S/DVB-DSNG coding and modulation schemes. The result is a capacity gain in the order of 30 % at a given transponder bandwidth and transmitted EIRP, depending on the modulation type and code rate. • Variable Coding and Modulation (VCM) may be applied to provide different levels of error protection to different service components (e.g. SDTV and HDTV, audio, multimedia). • In the case of interactive and point-to-point applications, the VCM functionality may be combined with the use of return channels, to achieve Adaptive Coding and Modulation (ACM). This technique provides more exact channel protection and dynamic link adaptation to propagation conditions, targeting each individual receiving terminal. ACM systems promise satellite capacity gains of up to 100 % - 200 %. In addition, service availability may be extended compared to a constant protection system (CCM) such as DVB-S or DVB-DSNG. Such gains are achieved by informing the satellite up-link station of the channel condition
(e.g. C/N+I) of each receiving terminal via the satellite or terrestrial return channels. • DVB-S and DVB-DSNG are strictly focused on a unique data format, the MPEG Transport Stream (ISO/IEC 13818-1 [1] or a reference to it). Extended flexibility to cope with other input data formats (such as multiple Transport Streams, or generic data formats) is now possible without significant complexity increase. The present document defines a "second generation" modulation and channel coding system (denoted the "System" or "DVB-S2" for the purposes of the present document) to make use of the improvements listed above. DVB-S2 is a single, very flexible standard, covering a variety of applications by satellite, as described below. It is characterized by: • a flexible input stream adapter, suitable for operation with single and multiple input streams of various formats (packetized or continuous); • a powerful FEC system based on LDPC (Low-Density Parity Check) codes concatenated with BCH codes, allowing Quasi-Error-Free operation at about 0,7 dB to 1 dB from the Shannon limit, depending on the transmission mode (AWGN channel, modulation constrained Shannon limit); • a wide range of code rates (from 1/4 up to 9/10); 4 constellations, ranging in spectrum efficiency from 2 bit/s/Hz to 5 bit/s/Hz, optimized for operation over non-linear transponders; • a set of three spectrum shapes with roll-off factors 0,35, 0,25 and 0,20; • Adaptive Coding and Modulation (ACM) functionality, optimizing channel coding and modulation on a frame-by-frame basis. The System has been optimized for the following broadband satellite applications: Broadcast Services (BS) Digital multi-programme Television (TV)/High Definition Television (HDTV) Broadcasting services to be used for primary and secondary distribution in the Fixed Satellite Service (FSS) and the Broadcast Satellite Service (BSS) bands. SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 7 DVB-S2 is intended to provide Direct-To-Home (DTH) services for consumer Integrated Receiver Decoder (IRD), as well as collective antenna systems (Satellite Master Antenna Television - SMATV) and cable television head-end stations (possibly with remodulation, see EN 300 429 [5]). DVB-S2 may be considered a successor to the current DVB-S standard EN 300 421 [2], and may be introduced for new services and allow for a long-term migration. BS services are transported in MPEG Transport Stream format. VCM may be applied on multiple transport stream to achieve a differentiated error protection for different services (TV, HDTV, audio, multimedia). Two modes are available: • NBC-BS (Non Backwards Compatible Broadcast Services) is not backwards-compatible with EN 300 421 [2]. • BC-BS (Backwards-Compatible Broadcast Services) is backwards-compatible to EN 300 421 [2] (see annex F). In fact, with a large number of DVB-S receivers already installed, backwards compatibility may be required for a period of time, where old receivers continue to receive the same capacity as before, while the new DVB-S2 receivers could receive additional capacity broadcasts. When the complete receiver population has migrated to DVB-S2, the transmitted signal can be modified to a non-backward compatible mode, thus exploiting the full potential of DVB-S2. To facilitate the reception of DVB-S services by DVB-S2 receivers, implementation of DVB-S in DVB-S2 chips is highly recommended. Interactive Services (IS) Interactive data services including Internet access DVB-S2 is intended to provide interactive services to consumer IRDs and to personal computers, where DVB-S2's forward path supersedes the current DVB-S standard EN 300 421 [2] for interactive systems. The return path can be implemented using various DVB interactive systems, such as DVB-RCS (EN 301 790 [6]), DVB-RCP (ETS 300 801 [7]), DVB-RCG (EN 301 195 [8]), DVB-RCC (ES 200 800 [9]). Data services are transported in (single or multiple) Transport Stream format according to EN 301 192 [4] (e.g. using Multiprotocol Encapsulation), or in (single or multiple) generic stream format. DVB-S2 can provide Constant Coding and Modulation (CCM), or Adaptive Coding and Modulation (ACM), where each individual satellite receiving station controls the protection mode of the traffic addressed to it. Input Stream Adaptation for ACM is specified in annex D. Digital TV Contribution and Satellite News Gathering (DTVC/DSNG) Digital television contribution applications by satellite consist of point-to-point or point-to-multipoint transmissions, connecting fixed or transportable uplink and receiving stations. They are not intended for reception by the general public. According to ITU-R Recommendation SNG.770-1 [10], SNG is defined as "Temporary and occasional transmission with short notice of television or sound for broadcasting purposes, using highly portable or transportable uplink earth stations .". Services are transported in single (or multiple) MPEG Transport Stream format. DVB-S2 can provide Constant Coding and Modulation (CCM), or Adaptive Coding and Modulation (ACM). In this latter case, a single satellite receiving station typically controls the protection mode of the full multiplex. Input Stream Adaptation for ACM is specified in annex D. Data content distribution/trunking and other professional applications (PS)
These services are mainly point-to-point or point-to-multipoint, including interactive services to professional head-ends, which re-distribute services over other media. Services may be transported in (single or multiple) generic stream format. The system can provide Constant Coding and Modulation (CCM), Variable Coding and Modulation (VCM) or Adaptive Coding and Modulation (ACM). In this latter case, a single satellite receiving station typically controls the protection mode of the full TDM multiplex, or multiple receiving stations control the protection mode of the traffic addressed to each one. In either case, interactive or non-interactive, the present document is only concerned with the forward broadband channel. DVB-S2 is suitable for use on different satellite transponder bandwidths and frequency bands. The symbol rate is matched to given transponder characteristics, and, in the case of multiple carriers per transponder (FDM), to the frequency plan adopted. Examples of possible DVB-S2 use are given in clause H.1. Digital transmissions via satellite are affected by power and bandwidth limitations. Therefore DVB-S2 provides for many transmission modes (FEC coding and modulations), giving different trade-offs between power and spectrum efficiency (see clause H.1). For some specific applications (e.g. broadcasting) modes such as QPSK and 8PSK, with their quasi-constant envelope, are appropriate for operation with saturated satellite power amplifiers (in single carrier per transponder configuration). When higher power margins are available, spectrum efficiency can be further increased to reduce bit delivery cost. In these cases also 16APSK and 32APSK can operate in single carrier mode close to the satellite HPA saturation by pre-distortion techniques. All the modes are appropriate for operation in quasi-linear satellite channels, in multi-carrier Frequency Division Multiplex (FDM) type applications. SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 8 DVB-S2 is compatible with Moving Pictures Experts Group (MPEG-2 and MPEG-4) coded TV services (see ISO/IEC 13818-1 [1]), with a Transport Stream packet multiplex. Multiplex flexibility allows the use of the transmission capacity for a variety of TV service configurations, including sound and data services. All service components are Time Division Multiplexed (TDM) on a single digital carrier. The present document: • gives a general description of the DVB-S2 system; • specifies the digitally modulated signal in order to allow compatibility between pieces of equipment developed by different manufacturers. This is achieved by describing in detail the signal processing principles at the modulator side, while the processing at the receive side is left open to different implementation solutions. However, it is necessary in the present document to refer to certain aspects of reception; • identifies the global performance requirements and features of the System, in order to meet the service quality targets. 2 References References are either specific (identified by date of publication and/or edition number or version number) or non-specific. • For a specific reference, subsequent revisions do not apply. • Non-specific reference may be made only to a complete document or a part thereof and only in the following cases: - if it is accepted that it will be possible to use all future changes of the referenced document for the purposes of the referring document; - for informative references. Referenced documents which are not found to be publicly available in the expected location might be found at http://docbox.etsi.org/Reference. NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee their long term validity. 2.1 Normative references The following referenced documents are indispensable for the application of the present document. For dated references, only the edition cited applies. For non-specific references, the latest edition of the referenced document (including any amendments) applies. [1] ISO/IEC 13818 (parts 1 and 2): "Information technology - Generic coding of moving pictures and associated audio information". [2] ETSI EN 300 421 (V.1.1.2): "Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for 11/12 GHz satellite services". [3] ETSI EN 301 210: "Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for Digital Satellite News Gathering (DSNG) and other contribution applications by satellite". [4] ETSI EN 301 192: "Digital Video Broadcasting (DVB); DVB specification for data broadcasting". [5] ETSI EN 300 429: "Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for cable systems". [6] ETSI EN 301 790: "Digital Video Broadcasting (DVB); Interaction channel for satellite distribution systems". SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 9 [7] ETSI ETS 300 801: "Digital Video Broadcasting (DVB); Interaction channel through Public Switched Telecommunications Network (PSTN)/ Integrated Services Digital Networks (ISDN)". [8] ETSI EN 301 195: "Digital Video Broadcasting (DVB); Interaction channel through the Global System for Mobile communications (GSM)". [9] ETSI ES 200 800: "Digital Video Broadcasting (DVB); DVB interaction channel for Cable TV distribution systems (CATV)". [10] ITU-R Recommendation SNG.770-1: "Uniform operational procedures for satellite news gathering (SNG)". [11] ETSI ETS 300 802: "Digital Video Broadcasting (DVB); Network-independent protocols for DVB interactive services". 2.2 Informative references The following referenced documents are not essential to the use of the present document but they assist the user with regard to a particular subject area. For non-specific references, the latest version of the referenced document (including any amendments) applies. [i.1] ETSI TS 102 005: "Digital Video Broadcasting (DVB); Specification for the use of Video and Audio Coding in DVB services delivered directly over IP protocols". [i.2] ETSI EN 300 744: "Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for digital terrestrial television". [i.3] ETSI TR 101 154: "Digital Video Broadcasting (DVB); Implementation guidelines for the use of MPEG-2 Systems, Video and Audio in satellite, cable and terrestrial broadcasting applications". [i.4] ETSI TR 101 162: "Digital Video Broadcasting (DVB); Allocation of Service Information (SI) codes for DVB systems". 3 Symbols and abbreviations 3.1 Symbols For the purposes of the present document, the following symbols apply: α Roll-off factor γ
Ratio between constellation radii for 16APSK and 32APSK c codeword C/N Carrier-to-noise power ratio (N measured in a bandwidth equal to symbol rate) C/N+I Carrier-to-(Noise+Interference) ratio 0121,,.,,ddddbchbchbchbchknkn−−−− BCH code redundancy bits d(x) BCH code remainder of the division between the generator polynomial and bchbchknx−m(x) DFL Data Field Length dmin LDPC code minimum distance Eb/N0 Ratio between the energy per information bit and single sided noise power spectral density Es/N0 Ratio between the energy per transmitted symbol and single sided noise power spectral density fN Nyquist frequency f0 Carrier frequency G PLS code generator matrix g(x) code generator polynomial SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 10 g1(x), g2(x), …, g12(x) polynomials to obtain BCH code generator polynomial i LDPC code information block 110,.,,−ldpckiii LDPC code information bits H(f) RC filters frequency transfer function H(n-k)xn LDPC code parity check matrix I, Q In-phase, Quadrature phase components of the modulated signal Kbch number of bits of BCH uncoded Block Nbch number of bits of BCH coded Block kldpc number of bits of LDPC uncoded Block
nldpc number of bits of LDPC coded Block
η PLFRAMING efficiency ηc code efficiency ηMOD number of transmitted bits per constellation symbol ηtot System spectral efficiency m BCH code information word m(x) BCH code message polynomial 0121,,.,,mmmmbchbchkk−− BCH code information bits M number of modulated symbols in SLOT 110,.,−−ldpcldpcknppp LDPC code parity bits P number of pilot symbols in a pilot block q code rate dependant constant for LDPC codes θ deviation angle in hierarchical constellations rm In-band ripple (dB) Rs Symbol rate corresponding to the bilateral Nyquist bandwidth of the modulated signal Ru Useful bit rate at the DVB-S2 system input
S Number of Slots in a XFECFRAME Ts Symbol period 3.2 Abbreviations For the purposes of the present document, the following abbreviations apply: 8PSK 8-ary Phase Shift Keying 16APSK 16-ary Amplitude and Phase Shift Keying 32APSK 32-ary Amplitude and Phase Shift Keying ACM Adaptive Coding and Modulation ASI Asynchronous Serial Interface AWGN Additive White Gaussian Noise BB BaseBand BC Backwards-Compatible NOTE: Referred to the system allowing partial stream reception by DVB-S receivers. BCH Bose-Chaudhuri-Hocquenghem multiple error correction binary block code BER Bit Error Ratio BS Bandwidth of the frequency Slot allocated to a service BS Broadcast Service BSS Broadcast Satellite Service BW BandWidth (at -3 dB) of the transponder CBR Constant Bit Rate CCM Constant Coding and Modulation CNI Carrier to Noise plus Interference ratio CRC Cyclic Redundancy Check D Decimal notation DD Decision Directed SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 11 DEMUX DEMUltipleXer DF Data Field DNP Deleted Null Packets DSNG Digital Satellite News Gathering DTH Direct To Home DTT Digital Terrestrial Television DVB Digital Video Broadcasting project DVB-S DVB System for satellite broadcasting NOTE: As specified in EN 300 421 [2].
DVB-S2 second generation DVB System for satellite broadcasting and unicasting NOTE: As specified in the present document. EBU European Broadcasting Union EN European Norm FDM Frequency Division Multiplex FEC Forward Error Correction FIFO First In First Out FSS Fixed Satellite Service GF Galois Field GS Generic Stream HDTV High Definition TeleVision HEX HEXadecimal notation HP High Priority IBO Input Back Off IF Intermediate Frequency IMUX Input MUltipleXer - filter IRD Integrated Receiver Decoder IS Interactive Services ISCR Input Stream Clock Reference ISI Input Stream Identifier ISSY Input Stream SYnchronizer ISSYI Input Stream SYnchronizer Indicator ITU International Telecommunications Union LDPC Low Density Parity Check (codes) LNB Low Noise Block LP Low Priority LSB Least Significant Bit MIS Multiple Input Stream MPE Multi-Protocol Encapsulation MPEG Moving Pictures Experts Group MSB Most Significant Bit NOTE: In DVB-S2 the MSB is always transmitted first. NBC Non-Backwards-Compatible MUX MUltipleX NA Not Applicable NP Null Packets NPD Null-Packet Deletion OBO Output Back Off OCT OCTal notation OMUX Output MUltipleXer - filter PER (MPEG TS) Packet Error Rate PID Packet IDentifier PL Physical Layer PLL Phase-Locked Loop PLS Physical Layer Signalling PRBS Pseudo Random Binary Sequence PS Professional Services PSK Phase Shift Keying SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 12 QEF Quasi-Error-Free QPSK Quaternary Phase Shift Keying RF Radio Frequency RO Roll-Off SDTV Standard Definition TeleVision SIS Single Input Stream SNG Satellite News Gathering SMATV Satellite Master Antenna TeleVision SOF Start Of Frame TDM Time Division Multiplex TS Transport Stream TV TeleVision TWTA Travelling Wave Tube Amplifier UPL User Packet Length VCM Variable Coding and Modulation TSDT Transport Stream Descriptor Table 4 Transmission system description 4.1 System definition The System is defined as the functional block of equipment performing the adaptation of the baseband digital signals, from the output of a single (or multiple) MPEG transport stream multiplexer(s) (ISO/IEC 13818-1 [1]), or from the output of a single (or multiple) generic data source(s), to the satellite channel characteristics. The System is designed to support source coding as defined in ISO/IEC 13818 [1], TR 101 154 [i.3]
and TS 102 005 [i.1]. Data services may be transported in Transport Stream format according to EN 301 192 [4] (e.g. using Multi-protocol Encapsulation), or Generic Stream format. If the received signal is above the C/N+I threshold, the Forward Error Correction (FEC) technique adopted in the System is designed to provide a "Quasi Error Free" (QEF) quality target. The definition of QEF adopted for DVB-S2 is "less than one uncorrected error-event per transmission hour at the level of a 5 Mbit/s single TV service decoder", approximately corresponding to a Transport Stream Packet Error Ratio PER< 10-7 before de-multiplexer. 4.2 System architecture According to figure 1, the DVB-S2 System shall be composed of a sequence of functional blocks as described below. Mode adaptation shall be application dependent. It shall provide input stream interfacing, Input Stream Synchronization (optional), null-packet deletion (for ACM and Transport Stream input format only), CRC-8 coding for error detection at packet level in the receiver (for packetized input streams only), merging of input streams (for Multiple Input Stream modes only) and slicing into DATA FIELDs. For Constant Coding and Modulation (CCM) and single input Transport Stream, Mode Adaptation shall consist of a "transparent" DVB-ASI (or DVB-parallel) to logical-bit conversion and CRC-8 coding. For Adaptive Coding and Modulation (ACM), Mode Adaptation shall be according to annex D. A Base-Band Header shall be appended in front of the Data Field, to notify the receiver of the input stream format and Mode Adaptation type. To be noted that the MPEG multiplex transport packets may be asynchronously mapped to the Base-Band Frames.
For applications requiring sophisticated merging policies, in accordance with specific service requirements (e.g. Quality of Service), Mode Adaptation may optionally be performed by a separate device, respecting all the rules of the DVB-S2 specification. To allow standard interfacing between Mode and Stream Adaptation functions, an optional modulator interface (Mode adaptation input interface) is defined, according to clauses I.1 (separate signalling circuit) or I.2 (in-band signalling). Stream adaptation shall be applied, to provide padding to complete a Base-Band Frame and Base-Band Scrambling. SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 13 Forward Error Correction (FEC) Encoding shall be carried out by the concatenation of BCH outer codes and LDPC (Low Density Parity Check) inner codes (rates 1/4, 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5, 5/6, 8/9, 9/10). Depending on the application area, the FEC coded block shall have length nldpc= 64 800 bits or 16 200 bits. When VCM and ACM is used, FEC and modulation mode may be changed in different frames, but remains constant within a frame. For Backwards Compatible modes, the bit-stream at the output of the FEC encoder shall be processed according to annex F. Bit interleaving shall be applied to FEC coded bits for 8PSK, 16APSK and 32APSK. Mapping into QPSK, 8PSK, 16APSK and 32APSK constellations shall be applied, depending on the application area. Gray mapping of constellations shall be used for QPSK and 8PSK. Physical layer framing shall be applied, synchronous with the FEC frames, to provide Dummy PLFRAME insertion, Physical Layer (PL) Signalling, pilot symbols insertion (optional) and Physical Layer Scrambling for energy dispersal. Dummy PLFRAMEs are transmitted when no useful data is ready to be sent on the channel. The System provides a regular physical layer framing structure, based on SLOTs of M = 90 modulated symbols, allowing reliable receiver synchronization on the FEC block structure. A slot is devoted to physical layer signalling, including Start-of-Frame delimitation and transmission mode definition. This mechanism is suitable also for VCM and ACM demodulator setting. Carrier recovery in the receivers may be facilitated by the introduction of a regular raster of pilot symbols (P = 36 pilot symbols every 16 SLOTs of 90 symbols), while a pilot-less transmission mode is also available, offering an additional 2,4 % useful capacity. Base-Band Filtering and Quadrature Modulation shall be applied, to shape the signal spectrum (squared-root raised cosine, roll-off factors 0,35 or 0,25 or 0,20) and to generate the RF signal.
BBFRAME FECFRAME PLFRAME FEC ENCODING MODULATION PL FRAMING BCH Encoder (nbch,kbch) PL Signalling & Pilot insertion
LDPC Encoder (nldpc,kldpc) BB Filter and Quadrature Modulation Bit mapper into constel-lations I
Q
QPSK,
8PSK,
16APSK,
32APSK rates 1/4,1/3,2/5 1/2, 3/5, 2/3, 3/4, 4/5, 5/6, 8/9, 9/10 α=0,35, 0,25,
0,20 to the RF satellite channelMAPPING BB SCRAM BLER
STREAM
ADAPTATION PADDER BB Signalling Merger Slicer MODE ADAPTATION PL SCRAM BLER
Single Input Stream Multiple Input Streams BBHEADER DATAFIELD Bit Inter-leaver Dummy PLFRAME Insertion Null-packet Deletion (ACM, TS) CRC-8 Encoder Input Stream Synchroniser Input
interface Null-packet Deletion (ACM, TS) Input Stream Synchroniser Input
interface DATA ACM COMMAND Dotted sub-systems are not relevant for
single transport stream broadcasting applications
CRC-8 Encoder LP stream for BC modes Buffer Buffer Mode Adaptation
Input Interface (optional)
Figure 1: Functional block diagram of the DVB-S2 System 4.3 System configurations Table 1 associates the System configurations to the applications areas. According to table 1, at least "Normative" subsystems and functionalities shall be implemented in the transmitting and receiving equipment to comply with the present document Guidelines for mode selection are given in annex H. SIST EN 302 307 V1.2.1:2009
ETSI ETSI EN 302 307 V1.2.1 (2009-08) 14 Table 1: System configurations and application areas System configurations Broadcast services Interactive services DSNG Professional services QPSK 1/4,1/3, 2/5
O N N N
1/2, 3/5, 2/3, 3/4, 4/5, 5/6, 8/9, 9/10 N N N N 8PSK 3/5, 2/3, 3/4, 5/6, 8/9, 9/10 N N N N 16APSK 2/3, 3/4, 4/5, 5/6, 8/9, 9/10 O N N N 32APSK 3/4, 4/5, 5/6, 8/9, 9/10 O N N N CCM
N N (see note 1) N N VCM
O O O O ACM
NA N (see note 2) O O FECFRAME (normal) 64 800 (bits) N N N N FECFRAME (short) 16 200 (bits) NA N O N Single Transport Stream
N N (see note 1) N N Multiple Transport Streams
O O (see note 2) O O Single Generic Stream
NA O (see note 2) NA O Multiple Generic Streams
NA O (see note 2) NA O Roll-off 0,35, 0,25 and 0,20
N N N N Input Stream Synchronizer
NA except
(see note 3) O (see note 3) O (see note 3) O (see note 3) Null Packet Deletion
NA except
(see note 3) O (see note 3) O (see note 3) O (see note 3) Dummy Frame insertion
NA except
(see note 3) N N N N = normative, O = optional, NA = not applicable. NOTE 1: Interactive service receivers shall implement CCM and Single Transport Stream. NOTE 2: Interactive Service Receivers shall implement ACM at least in one of the two options: Multiple Transport Streams or Generic Stream (single/multiple input). NOTE 3: Normative for single/multiple TS input stream(s) combined with ACM/VCM or for multiple TS input streams combined with CCM.
Within the present document, a number of configurations and mechanisms are defined as "Optional". Configurations and mechanisms explicitly indicated as "optional" within the present document, for a given application area, need not be implemented in the equipment to comply with the present document. Nevertheless, when an "optional" mode or mechanism is implemented, it shall comply with the specification as given in the present document. 5 Subsystems specification The subsystem specification description is organized according to the functional block diagram of figure 1. 5.1 Mode adaptation This sub-system shall perform Input Interfacing, Input Stream Synchronization (optional), Null-packet deletion (for TS input streams and ACM only), CRC-8 encoding for error detection (for packetized input streams only), input stream merging (for multiple input streams only) and input stream slicing in DATA FIELDs. Finally, base-band signalling shall be inserted, to notify the receiver of the adopted Mode Adaptation format. According to figure 3, the input sequence(s) is (are): • Single or multiple Transport Streams (TS). • Single or multiple Generic Streams (p
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