ETSI TS 102 721-6 V1.2.1 (2013-08)

Satellite Earth Stations and Systems (SES); Air Interface for S-band Mobile Interactive Multimedia (S-MIM); Part 6: Protocol Specifications, System Signalling

RTS/SES-00338

General Information

• Status: Published
• Publication Date: 07-Aug-2013
• Technical Committee: SES SCN - Satellite Communications and Navigation
• Current Stage: 12 - Completion
• Due Date: 23-Aug-2013
• Completion Date: 08-Aug-2013
• Mandate: M/496

Standards Content (Sample)

Technical Specification
Satellite Earth Stations and Systems (SES);
Air Interface for S-band Mobile Interactive Multimedia (S-MIM);
Part 6: Protocol Specifications, System Signalling

2 ETSI TS 102 721-6 V1.2.1 (2013-08)

Reference
RTS/SES-00338
Keywords
MSS, satellite
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ETSI
3 ETSI TS 102 721-6 V1.2.1 (2013-08)
Contents
Intellectual Property Rights . 5
Foreword . 5
Introduction . 5
1 Scope . 6
2 References . 6
2.1 Normative references . 6
2.2 Informative references . 6
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 8
4 General Description . 9
5 Forward link . 9
5.1 Forward link Control Plane Protocol Stack . 9
5.2 Forward link Signalling . 10
5.2.1 Forward link signalling for SSA support . 10
5.2.1.1 SSA Configuration Table (SCT) . 10
5.2.1.2 SSA Access Table (SAT) . 13
5.2.1.3 SSA Dynamic Table (SDT) . 14
5.2.1.4 SSA Signalling Load . 15
5.2.2 Forward link signalling for QS-CDMA support . 15
5.2.2.1 QS-CDMA Configuration Table (QSCT) . 16
5.2.2.2 QS-CDMA Dynamic Table (QSDT) . 18
5.2.2.3 QS-CDMA Power Correction Table (QSPCT) . 19
5.2.2.4 QS-CDMA Terminal Information Message (QSTIM) . 20
5.2.2.5 Descriptor Coding . 21
5.2.2.5.1 Descriptor identification . 21
5.2.2.5.2 QS-CDMA Correction Message . 21
5.2.2.5.3 QS-CDMA RoHC Feedback Message . 22
5.2.2.5.4 QS-CDMA Capacity Allocation Hub Req . 23
5.2.2.5.5 QS-CDMA Capacity Allocation Ack . 23
5.2.2.5.6 QS-CDMA Capacity Release Hub Req . 25
5.2.2.5.7 QS-CDMA Capacity Reallocation Hub Req . 25
5.2.2.5.8 QS-CDMA Capacity Reallocation Ack . 26
5.2.2.5.9 QS-CDMA Handover Ack . 27
5.2.2.5.10 QS-CDMA LogOn Ack . 28
5.2.2.6 Repetition Rates . 28
5.2.2.7 Signalling load . 28
5.2.3 Forward link signalling for Link Layer support . 29
5.2.3.1 Link Layer configuration Table (LLCT) . 29
5.2.3.2 Unequivocal ACK . 30
5.2.3.3 CRC based ACK . 30
5.2.4 Standard section headers . 31
5.2.4.1 SI section header . 31
5.2.4.2 DSM-CC private section header . 32
5.2.5 SSA Signalling Considerations for CGC . 33
6 Return link . 34
6.1 Return link Control Plane Protocol Stacks . 34
6.2 Return link Signalling . 34
6.2.1 QS-CDMA Signalling Unit . 34
6.2.2 Descriptor Coding . 35
6.2.2.1 Descriptor identification . 35
6.2.2.2 QS-CDMA Logon . 36
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4 ETSI TS 102 721-6 V1.2.1 (2013-08)
6.2.2.3 QS-CDMA Capacity Allocation Req . 37
6.2.2.4 QS-CDMA Capacity Release Req . 38
6.2.2.5 QS-CDMA Capacity Reallocation Req . 38
6.2.2.6 QS-CDMA Handover Req . 39
Annex A (normative): Transport of Forward Link Signalling over DVB-SH . 40
A.1 S-MIM Map Table . 41
A.2 Linkage descriptor (private data) . 42
A.3 S-MIM content descriptor . 43
History . 46

ETSI
5 ETSI TS 102 721-6 V1.2.1 (2013-08)
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://ipr.etsi.org).
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 Technical Specification (TS) has been produced by ETSI Technical Committee Satellite Earth Stations and
Systems (SES).
The present document is part 6 of a multi-part deliverable. Full details of the entire series can be found in part 1 [2].
Introduction
The S-MIM system specified herein is designed to provide:
• Interactive mobile broadcast services.
• Messaging services for handhelds and vehicular terminals, capable of serving millions of terminals due to a
novel optimized air-interface in the return link.
• Real-time emergency services such as voice and file transfer, mainly addressing institutional users
on-the-move such as fire brigades, civil protection, etc.
Inside the S-band, the 2 GHz MSS band is of particular interest for interactive multimedia, since it allows two-way
transmission. Typically, the DVB-SH standard [i.5] is applied for broadcast transmission of user services; ESDR [i.1] or
DVB-NGH [i.6] standards are other alternatives. Essential requirements under the R&TTE directive are covered by the
harmonized standard EN 302 574 [i.2], [i.3] and [i.4].
The present document supersedes the previous version of the document and is recommended for new implementations.
In case DVB-SH is used in the forward link, the changes with respect to the previous version are backward compatible.
The technology applied has been developed in the framework of the ESA funded project "DENISE" (ESTEC/Contract
Number 22439/09/NL/US).
ETSI
6 ETSI TS 102 721-6 V1.2.1 (2013-08)
1 Scope
The present document specifies the S-MIM (S-band Mobile Interactive Multimedia) system in which a standardized
S-band satellite mobile broadcast system is complemented by the addition of a return channel
The present document is part 6 of the standard and concerns aspects of the air interface for the S-band Mobile
Interactive Multimedia (S-MIM) system, and in particular it specifies the system signalling.
The other parts are listed in the foreword of part 1 [2].
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
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 necessary for the application of the present document.
[1] ETSI EN 300 468: "Digital Video Broadcasting (DVB); Specification for Service Information (SI)
in DVB systems".
[2] ETSI TS 102 721-1: "Satellite Earth Stations and Systems (SES); Air Interface for S-band Mobile
Interactive Multimedia (S-MIM); Part 1: General System Architecture and Configurations".
[3] ETSI TS 102 721-3: "Satellite Earth Stations and Systems (SES); Air Interface for S-band Mobile
Interactive Multimedia (S-MIM); Part 3: Physical Layer Specification, Return Link Asynchronous
Access".
[4] ETSI TS 102 721-4: "Satellite Earth Stations and Systems (SES); Air Interface for S-band Mobile
Interactive Multimedia (S-MIM); Part 4: Physical Layer Specification, Return Link Synchronous
Access".
[5] ETSI TS 102 721-5: "Satellite Earth Stations and Systems (SES); Air Interface for S-band Mobile
Interactive Multimedia (S-MIM); Part 5: Protocol Specifications, Link Layer".
[6] IETF RFC 4944: "Transmission of IPv6 Packets over IEEE 802.15.4 Networks".
[7] ETSI EN 301 790: "Digital Video Broadcasting (DVB); Interaction channel for satellite
distribution systems".
[8] ETSI TS 102 470-2: "Digital Video Broadcasting (DVB); IP Datacast: Program Specific
Information (PSI)/Service Information (SI); Part 2: IP Datacast over DVB-SH".
2.2 Informative references
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] ETSI EN 302 550 (all parts and sub-parts): "Satellite Earth Stations and Systems (SES); Satellite
Digital Radio (SDR) Systems".
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7 ETSI TS 102 721-6 V1.2.1 (2013-08)
[i.2] ETSI EN 302 574-1: "Satellite Earth Stations and Systems (SES); Harmonized standard for
satellite earth stations for MSS operating in the 1 980 MHz to 2 010 MHz (earth-to-space) and
2 170 MHz to 2 200 MHz (space-to-earth) frequency bands; Part 1: Complementary Ground
Component (CGC) for wideband systems: Harmonized EN covering the essential requirements of
article 3.2 of the R&TTE Directive".
[i.3] ETSI EN 302 574-2: "Satellite Earth Stations and Systems (SES); Harmonized standard for
satellite earth stations for MSS operating in the 1 980 MHz to 2 010 MHz (earth-to-space) and
2 170 MHz to 2 200 MHz (space-to-earth) frequency bands; Part 2: User Equipment (UE) for
wideband systems: Harmonized EN covering the essential requirements of article 3.2 of the
R&TTE Directive".
[i.4] ETSI EN 302 574-3: "Satellite Earth Stations and Systems (SES); Harmonized standard for
satellite earth stations for MSS operating in the 1 980 MHz to 2 010 MHz (earth-to-space) and
2 170 MHz to 2 200 MHz (space-to-earth) frequency bands; Part 3: User Equipment (UE) for
narrowband systems: Harmonized EN covering the essential requirements of article 3.2 of the
R&TTE Directive".
[i.5] ETSI TS 102 585: "Digital Video Broadcasting (DVB); System Specifications for Satellite
services to Handheld devices (SH) below 3 GHz".
[i.6] DVB BlueBook A160: "Next Generation broadcasting system to Handheld, physical layer
specification (DVB-NGH)".
[i.7] ISO/IEC 13818-1: "Information technology -- Generic coding of moving pictures and associated
audio information: Systems".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
2 GHz MSS band: 1 980 MHz to 2 010 MHz (earth-to-space) and 2 170 MHz to 2 200 MHz (space-to-earth) frequency
bands
NOTE: These paired bands are assigned to MSS.
architecture: abstract representation of a communications system
NOTE: Three complementary types of architecture are defined:
� Functional Architecture: the discrete functional elements of the system and the associated logical
interfaces.
� Network Architecture: the discrete physical (network) elements of the system and the associated
physical interfaces.
� Protocol Architecture: the protocol stacks involved in the operation of the system and the
associated peering relationships.
collector: terrestrial components that "collect" return link transmissions from terminals and forward them towards the
ground segment
control plane: plane that has a layered structure and performs the call control and connection control functions; it deals
with the signalling necessary to set up, supervise and release calls and connections
repeater: terrestrial components that (mainly) repeat the satellite signal in the forward link
S-band: equivalent to 2 GHz MSS band
ETSI
8 ETSI TS 102 721-6 V1.2.1 (2013-08)
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
ACK ACKnowledgement
bslbf bit string, left bit first.
BW Bandwidth
CAC Call Admission Control
CDMA Code Division Multiple Access
CGC Complementary Ground Component
CID Context Identifier
CRC Cyclic Redundancy Check
DAMA Dynamic Assignment Multiple Access
DSM-CC Digital Storage Media Command and Control
DVB-SH Digital Video Broadcasting, Satellites services to Handhelds
EIRP Equivalent Isotropic Radiated Power
EOC Edge Of Coverage
ESA European Space Agency
ESDR ETSI Satellite Digital Radio
FEC Forward Error Correction
FL Forward Link
FLS Forward Link Signalling
FLSS Forward Link Sub-System
FWD Forward (link)
GHz Giga Hertz
ID Identifier
IMSI International Mobile Subscriber Identity
IP Internet Protocol
IPSec IP Security
Ipv6 Internet Protocol version 6
LLC/SNAP Logical Link Control/Sub-Network Access Protocol
LLCT Link Layer Configuration Table
LLMT Link Layer Map Table
MAC Medium Access Control
MAI Multiple Access Interference
MPE Multiprotocol Encapsulation
MPEG Moving Pictures Experts Group
MPEG-TS MPEG Transport Stream
MSB Most Significant Bit
MSS Mobile Satellite Services
NIT Network Information Table
PAT Program Association Table
PCCH Physical Control Channel
PDCH Physical Data Channel
PID Program Identifier
PMT Program Map Table
PN Pseudo Noise
PSI Program Specific Information
QS-CDMA Quasi Synchronous CDMA
QSCT QS-CDMA Configuration Table
QSDT QS-CDMA Dynamic Table
QSPCT QS-CDMA Power Correction Table
QSTIM QS-CDMA Terminal Information Message
R&TTE Radio and Telecommunications Terminal Equipment
RACH Random Access CHannel
RFC Request For Comments
RFU Reserved for Future Use
RL Return Link
RLE Return Link Encapsulation
RLSS Return Link Sub-System
rpchof remainder polynomial coefficients, highest order first
ETSI
9 ETSI TS 102 721-6 V1.2.1 (2013-08)
RTN Return (link)
SAT SSA Access Table
SCT SSA Configuration Table
SDR Satellite Digital Radio
SDT SSA Dynamic Configuration Table
SF Spreading Factor
SFN Single Frequency Network
SI Service Information
simsbf signed integer, most significant bit first
S-MIM S-band Mobile Interactive Multimedia
SMT SSA Map Table
SNIR Signal to Noise plus Interference Ratio
SNR Signal to Noise Ratio
SS1 Service Segment 1
SS2 Service Segment 2
SS3 Service Segment 3
SSA Spread Spectrum Aloha
TFI Transport Format Indication
TMSI Temporary Mobile Subscriber Identity
TS Transport stream
TX Transmission or Transmit
uimsbf unsigned integer, most significant bit first
UMTS Universal Mobile Telecommunications System
USIM Universal Subscriber Identity Module
WGS World Geodetic System
4 General Description
The management of S-MIM resources concerns long term and short term aspects.
The Control Plane is concerned with dynamic (short term) resource management with the associated signalling needed
to manipulate communication channels.
The clauses below deal with the Forward and Return Links separately.
5 Forward link
5.1 Forward link Control Plane Protocol Stack
In the Control Plane, most of the system signalling is provided through signalling tables following DVB-SI format [1]).
The way such signalling tables are transported over the FWD link and encapsulated in MPEG-TS, depends on the
adopted technology. An informative annex explains how to carry S-MIM forward link signalling when using DVB-SH.
However, the signalling for authentication needs to communicate with the USIM. In order to allow reuse of existing
technologies, UMTS data units are employed for authentication signalling going through the USIM. Hence, the protocol
stack for the Control Plane has a specific branch to allow the transport of this type of data packets over MPE/MPEG. To
achieve compatibility with the USIM, the use of MPE with the LLC/SNAP protocol is selected to transport data other
than IP, as shown in Figure 5.1.
ETSI
10 ETSI TS 102 721-6 V1.2.1 (2013-08)

Figure 5.1: FWD link Control Plane Protocol Stack for SS1 and SS2
5.2 Forward link Signalling
5.2.1 Forward link signalling for SSA support
The signalling over the forward link for SSA support is organized into the following tables: SSA Configuration Table
(SCT), SSA Access Table (SAT), SSA Dynamic Table (SDT).
The following clauses show the organization of the different tables.
5.2.1.1 SSA Configuration Table (SCT)
This table is carried in one or more section (each section is in fact limited to 1 024 bytes) with each section having the
format described in Table 5.1.
ETSI
11 ETSI TS 102 721-6 V1.2.1 (2013-08)
Table 5.1: SSA Configuration Table
Syntax No. of bits Information
Reserved Mnemonic
Information
(see note)
SSA_configuration_section(){
SI_private_section_header  64 -
rl_carriers_loop_count 3 5 uimsbf
for(i=0;i<= rl_carriers_loop_count;i++){
rl_carrier_id 3 5 uimsbf
uplink_polarization 6 2 bslbf
centre_frequency 32 uimsbf
chip_rate 2 22 uimsbf
preamble_len 16 uimsbf
num_spreading_codes 8 uimsbf
preamble_s1_index 16 uimsbf
preamble_s2_index 16 uimsbf
data_scrambling_code_index 16 uimsbf
spread_factor_control 8 uimsbf
WH_code_control 8 uimsbf
WH_code_data 8 uimsbf
tfi_count 3 5 uimsbf
for(k=0,k<=tfi_count;k++){  uimsbf
tfi_value 3 5 uimsbf
spread_factor_data 8 uimsbf
Info_lenght 10 uimsbf
crc_lenght 2 2 uimsbf
control_spread 2 uimsbf
control_power 4 uimsbf
pilot_num 4 uimsbf
}
}
CRC_32 32 rpchof
}
NOTE: Reserved bits are of type bslbf, and shall precede the Information bits on the same line.

The SCT table parameters are:
• SI_private_section_header. See clause 5.2.4.1.
• rl_carriers_loop_count. This represents the number of SSA return link carriers which are described in
Table 5.1.
• rl_carrier_id. It is the ID of the return link carrier for which the following parameters apply.
• up_link_polarization. This represents the tx polarization (see Table 5.1) which should be used by terminals
accessing that carrier.
• centre_frequency. This is the centre frequency of the considered RL carrier in multiples of 100 Hz.
• chip_rate. It is the chip rate expressed in chips/s.
• preamble_len. It represents the preamble length in chips.
• num_spreading_codes. Number of different codes which can be used on that carrier.
• preamble_s1_index. This represents the index of the preamble signature sequence s1 (indicated with n in
clause 7.2.1 of TS 102 721-3 [3]). If num_spreading_codes is greater than one the terminal will randomly
select with uniform probability a signature code s1 with index between preamble_s1_index and
(preamble_s1_index+ num_spreading_codes-1).
ETSI
12 ETSI TS 102 721-6 V1.2.1 (2013-08)
• preamble_s2_index. This is the index of the sequence s2 constituting the hierarchical preamble. It indicates
which of the 2 complementary sequences defined in clause 7.2.2.1 of TS 102 721-3 [3] shall be used,
according to the following mapping:
- 0 means sequence 1
- 1 means sequence 2
Other values are reserved for future use.
• data_scrambling_code_index. It is the index of the scrambling code used in the data part of the message. If
num_spreading_codes is greater than one the terminal will actually use a scrambling code index (indicated
with n in clause 7.1.2 of TS 102 721-3 [3]) which is obtained as the concatenation of the 8 least significant bits
of premble_s1_index with the 16 bits of data_scambling_code_index. Otherwise the remaining 8 bits are set to
0.
• spread_factor_control. Spreading factor of the control channel.
• WH_code_control. Walsh-Hadamard code index to be used for the control channel.
• WH_code_data. Walsh-Hadamard code index to be used for data channel.
• tfi_count. Number of allowed different bursts.
• tfi_value. It represents the TFI value corresponding to each allowed configuration. The terminal will use such
value for its TFI field in the PCCH.
• spread_factor_data. It is the SF for the data channel.
• Info_lenght. Nominal size of the RACH data burst (in 4 bits nibbles), including link layer encapsulation header
but no CRC. For the currently defined RACH data burst lengths, the following correspondence apply:
1 200 bits � Info_length=300
600 bits � Info_length=150
300 bits � Info_length=75
Although the actual size of RACH data bursts might vary and will compensated by rate matching, it is
recommended to keep the effective size of the RACH data burst length within ± 10% of the nominal sizes.
• crc_length. A value of 0 indicates that no CRC is appended to the message before FEC coding. Values of 1,
and 2 indicate the use of a CRC of length respectively 8 bits, 16 bits. A value of 3 is reserved for future use,
e.g. for a CRC of length 32 bits.
• control_spread. Number of frames in which the control channel is sent. A value of 0 means that the control
channel is transmitted over all frames. A value > 0 indicates that the length of PCCH is equal to control_spread
× FRAME_GROUP_LENGTH frames. The FRAME_GROUP_LENGTH = 6 for the 5 kbit/s PDCH channel
and 3 for the 10 kbit/s PDCH. The FRAME_GROUP_LENGTH is not signalled but can be implicitly derived
from the ratio of SF between the PCCH and PDCH which are instead signalled.
• control power. Indicate the voltage gain of the control channel relatively to the data channel (see Table 5.3).
• pilot_num. Number of pilot symbols in a slot of the control channel (the complement to ten are TFI bits).
• CRC_32: This is a 32-bit field that contains the CRC value that gives a zero output of the registers in the
decoder defined in annex B of EN 300 468 [1] after processing the entire section.
Table 5.2: Polarization table
Polarization Description
00 Linear-horizontal
01 Linear-vertical
10 Circular-left
11 Circular-right
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13 ETSI TS 102 721-6 V1.2.1 (2013-08)
Table 5.3: Quantization of the gain parameter
Signalling values for β Quantized amplitude ratios (β)
15 1,0
14 0,9333
13 0,8666
12 0,8000
11 0,7333
10 0,6667
9 0,6000
8 0,5333
7 0,4667
6 0,4000
5 0,3333
4 0,2667
3 0,2000
2 0,1333
1 0,0667
0 Switch off
5.2.1.2 SSA Access Table (SAT)
This table is carried in one or more section (each section is in fact limited to 1 024 bytes) with each section having the
format described in Table 5.4.
Table 5.4: SSA Access Table
No. of bits
Information
Syntax Reserved
Information Mnemonic
(see note)
SSA_access_section(){
SI_private_section_header  64 -
FL_EIRP 8 uimsbf
K_factor 8 uimsbf
Rl_TX_EIRP_flag 6 2 bslbf
service_class_loop_count 8 uimsbf
for(i=0;i<= service_class_loop_count;i++) {
service_class_id 8 uimsbf
allowed_rl_carrier_index 32 uimsbf
load_flag_count 2 6 uimsbf
for(i=0;i load_flag 2 6 uimsbf
Back_off_time 8 uimsbf
Persistence_index 16 uimsbf
ack_time_out 16 uimsbf
max_retransmissions 8 uimsbf
R_max 8 uimsbf
}
}
CRC_32 32 rpchof
}
NOTE: Reserved bits are of type bslbf, and shall precede the Information bits on the same line.

The SAT table parameters are:
• SI_private_section_header. See clause 5.2.4.1.
• FL_EIRP. It is the FL carrier EIRP at EOC in multiples of 0,5 dBW.
• K_factor. It is a factor which shall be used by the terminal to compute its Tx EIRP. The parameter K is equal
to C/(N + I )| – G where C/(N + I )| is the target value used for the desired C/(N + I ) at the satellite
0 0 T S 0 0 T 0 0
transponder input. G is the satellite antenna gain at EOC. K is expressed in multiples of -0,5 dB.
S
ETSI
14 ETSI TS 102 721-6 V1.2.1 (2013-08)
• RI_tx_EIRP_flag. It defines the TX control strategy to be used by the terminal according to the options
detailed in Table 5.5.
• service_class_id. It is the ID of the class of service for which the following parameters apply.
• allowed_rl_carrier_index. It is a 32 bit integer representing the RL carriers (described by the SCT table) which
can be used for the SSA access by terminal_class_id terminals. The i-th bit of the integer, if 1, allow use of
carrier i-th for the SSA access.
• load_flag. It is the value of the load flag for which the following access parameters apply.
• back_off_time. It is the number of time units for packet retransmission protocol. The time unit is one physical
layer frame (10 ms).
• persistence_index. It is a value from which the probability of transmitting at the next time step (in unit of
back_off time) is computed. The probability (persistence) is: persistence=1/2^(persistence_index/2).
• ack_time_out. Time out for ack expressed in physical layer frames (10 ms).
• max_retransmissions. Maximum number of retransmission of the same packet.
• R_max. It is a parameter used for computing the TX EIRP depending on the value of the Rl_tx_EIRP_flag as
detailed in Table 5.5.
• CRC_32: This is a 32-bit field that contains the CRC value that gives a zero output of the registers in the
decoder defined in annex B of EN 300 468 [1] after processing the entire section.
Table 5.5: Syntax of Rl_tx_EIRP_flag
Value of TX control strategy Meaning of R_max
Rl_tx_EIRP_flag
00 No SSA terminal can TX None
01 TX control strategy #1 from TS 102 721-3 [3] Max value of the additional power
randomization in multiples of 0,5 dB
10 TX control strategy #2 from TS 102 721-3 [3] Max value of the SNR fluctuation in
multiples of 0,5 dB
11 All SSA terminals shall TX at maximum power level None

5.2.1.3 SSA Dynamic Table (SDT)
This table is carried in one or more section (each section is in fact limited to 1 024 bytes) with each section having the
format described in Table 5.6.
The SDT table parameters are self-describing except for:
• current_sat_noise. It is the current noise plus interference at the satellite transponder input expressed in
multiples of -0,5 dBm for the considered RL carrier slots.
ETSI
15 ETSI TS 102 721-6 V1.2.1 (2013-08)
Table 5.6: SSA Dynamic Table
Syntax No. of bits Information
Reserved Mnemonic
Information
(see note)
SSA_dynamic_section(){
SI_private_section_header  64 -
rl_carriers_loop_count 3 5 uimsbf
for(i=0;i<= rl_carriers_loop_count;i++){
rl_carrier_id 3 5 uimsbf
current_sat_noise 8 uimsbf
service_class_loop_count 8 uimsbf
for(i=0;i<=service_class_loop_count;i++){
service_class_id 8 uimsbf
load_flag 2 6 uimsbf
}
}
CRC_32 32 rpchof
}
NOTE: Reserved bits are of type bslbf, and shall precede the Information bits on the same line.

5.2.1.4 SSA Signalling Load
Table 5.7: Recommended table parameters
Parameter Recommended Value
SCT and SAT table transmit periodicity about 10 seconds.
(range 3 seconds to 30 seconds).
SDT transmit periodicity about 1 second.
(range 0,5 second to 2 seconds).
SCT minimum length 320 bits.
(Assuming worst case of 5 MHz RL slot used by 16 carriers of 240 kchip/s and
with 32 TFI values, the length of the SCT would become 4 200 bits).
SAT minimum length 240 bits.
(Assuming 8 service classes and 4 load flags values, the length of SCT would
become 2 560 bits).
SDT minimum length 144 bits.
(Assuming 8 service classes and 16 RL carriers, the length of SDT would
become 2 536 bits).
The overall impact of specific signalling for SSA would thus be in the order of a few kbit/s per 5 MHz channel.
5.2.2 Forward link signalling for QS-CDMA support
The signalling for QS-CDMA is organized into the following tables: QS-CDMA Configuration Table (QSCT), QS-
CDMA Dynamic Table (QSDT), QS-CDMA Power Correction Table (QSPCT) and QS-CDMA Terminal Information
Message (QSTIM)
The assignment of PID to the tables shall consider the kind of information and its priority. That the following
assignment policy is recommended:
• A PID is assigned to the set of QSCT and QSDT tables as they are small and low priority tables.
• A PID is assigned to QSPCT table because it conveys high priority information; essential for terminal
synchronization. In addition the size of the table depends on the number of active links which may be high.
Therefore this table shall be scheduled with a low period in comparison to other tables.
• A PID is assigned to QSTIM which conveys QS-CDMA system signalling like CAC/DAMA requests. This
table, as the QSPCT does, conveys high priority information. However, the size of the QSTIM is smaller than
QSPCT so the first one shall pre-empt the second.
The following clauses show the organization of the different tables.
ETSI
16 ETSI TS 102 721-6 V1.2.1 (2013-08)
5.2.2.1 QS-CDMA Configuration Table (QSCT)
The syntax of QSCT is shown in Table 5.8. It shall be segmented in QS-CDMA Configuration sections using the syntax
described in EN 300 468 [1]. Any sections forming part of a QSCT shall be transmitted in TS packets with a PID value
assigned in the PMT.
Table 5.8 defines the static configuration of the QS-CDMA subsystem.
Table 5.8 may be mapped either to the real time transport channel or into the non-real time transport channel of the
FWD link radio interface.
Table 5.8: QS-CDMA Configuration Table (QSCT)
Syntax No. of bits Information
Reserved Information Mnemonic
(see note)
qscdma_configuration_table () {
SI_private_section_header () 64 -
fwd_snir_total 16 uimsbf
flsl_timeout 8 uimsbf
lr_timeout 8 uimsbf
lr_max_time_before_retry 8 uimsbf
lr_max_retries 8 uimsbf
car_timeout 8 uimsbf
car_max_time_before_retry 8 uimsbf
car_max_retries 8 uimsbf
max_time_without_correction 8 uimsbf
nof_rl_spots 8 uimsbf
rl_spot_info_length 16 uimsbf
for (i=0; i rl_spot_id 8 uimsbf
polarization_id 1 2 bslbf
Rfu 5 uimsbf
nof_rl_slots 8 uimsbf
rl_slot_info_length 16 uimsbf
for (j=0; j rl_slot_id 8 uimsbf
center_frequency 32 uimsbf
chip_rate 1 3 bslbf
Rfu 4 uimsbf
rach_preamble_length 16 uimsbf
rach_preamble_seed 10 uimsbf
rach_pilot_seed 1 15 uimsbf
rach_scrambling_code 24 uimsbf
rach_spreading_i_code 3 9 uimsbf
rach_spreading_q_code 3 9 uimsbf
rach_ref_eirp_stationary 10 simsbf
rach_ref_eirp_mobile 10 simsbf
rach_ref_eirp_high_speed_mobile 10 simsbf
qscdma_small_power_step 4 uimsbf
qscdma_large_power_step 6 uimsbf
qscdma_pilot_seed 1 15 uimsbf
qscdma_pilot_gain_factor 2 4
pattern_advantage_bias 8 simsbf
}
}
CRC_32 32 rpchof
}
NOTE: Reserved bits are of type bsblf, and shall precede the information bits on the same line.

ETSI
17 ETSI TS 102 721-6 V1.2.1 (2013-08)
Semantics for the qscdma_configuration_table:
• SI_private_section_header: See clause 5.2.4.1.
• fwd_snir_total: Expected FWD link SNIR for a terminal located at the edge of coverage with the worst case
G/T in clear sky conditions.
• flsl_timeout: Is the time the terminal uses to trigger the event "Forward link synchronization loss" as defined in
TS 102 721-3 [3]. It is expressed in steps of 100 ms.
• lr_timeout: The LogOn Request timeout is the time the terminal waits for a Hub ack upon a LogOn request. It
is expressed in steps of 100 ms.
• lr_max_time_before_retry: Maximum time before LogOn Request retry as specified in TS 102 721-3 [3]. It is
expressed in steps of 100 ms.
• lr_max_retries: Maximum number of LogOn Request retries.
• car_timeout: The Capacity Allocation Request timeout is the time the terminal waits for a Hub ack upon a call
admission Request. It is expressed in steps of 100 ms.
• car_max_time_before_retry: Maximum time before Capacity Allocation Request retry as specified in
TS 102 721-3 [3]. It is expressed in steps of 100 ms.
• car_max_retries: Maximum number of Capacity Allocation Request retries.
• max_time_without_correction: This is the maximum time the terminal can keep transmitting a QS-CDMA
carrier in absence of physical layer corrections generated by the Hub. It is expressed in steps of 100 ms.
• nof_rl_spots: Defines the number of the return link spots that the Hub manages.
• rl_spot_info_length: Is the length in bytes of the return link spot loop.
• rl_spot_id: The spot identifier.
• polarization_id: This signals the polarization used in the current return link spot. Its allowed values are shown
in Table 5.9.
Table 5.9: Polarization
Polarization Description
00 Linear Horizontal
01 Linear Vertical
10 Circular Left Hand
11 Circular Right Hand
• nof_rl_slots: Defines the number of return link slots described in Table 5.8.
• rl_slot_info_length: Is the length in bytes of the return link slot loop.
• rl_slot_id: Is the return link slot identifier that will be used further when resources are allocated.
• center_frequency: Is the center frequency if the current return link slot.
• chip_rate: This parameter states the chip rate being used in the current return link slot. The allowed values are
shown in Table 5.10.
Table 5.10: QS-CDMA Chip rate
Chip Rate Description
000 4 096 kchips/s
001 512 kchips/s
010 256 kchips/s
other RFU
ETSI
18 ETSI TS 102 721-6 V1.2.1 (2013-08)
• rach_preamble_length: Is the preamble length that shall be used for the QS-CDMA random access
mechanism. It is expressed in symbols.
• rach_preamble_seed: Is the seed for the PN sequence that generates the preamble as defined in
TS 102 721-4 [4].
• rach_pilot_seed: Is the seed for the PN sequence that generates the RACH pilot symbols as defined in
TS 102 721-4 [4].
• rach_scrambling_code: Is the scrambling code to use for the random access carrier.
• rach_spreading_i_code: Is the spreading code for the I branch.
• rach_spreading_q_code: Is the spreading code for the Q branch.
• rach_ref_eirp_stationary: The EIRP of the Random Access carrier transmitted by a terminal at the satellite
reference contour for reception that results in the target Es/(No+Io) being received at the Hub in clear sky
conditions and without MAI. This value is used in stationary scenarios. It is expressed in steps of 0,1 dB.
• rach_ref_eirp_mobile: Equal to ssa_ref_eirp_stationary but under moderate speed scenarios (≤ 120 Km/h). It
is expressed in steps of 0,1 dB.
• rach_ref_eirp_high_speed_mobile: Equal to ssa_ref_eirp_stationary but under moderate high scenarios
(> 120 Km/h). It is expressed in steps of 0,1 dB.
• qscdma_small_power_step: This is the small step used for the power control closed-loop algorithm. It is
expressed in steps of 0,1 dB.
• qscdma_large_power_step: This is the large step used for the power control closed-loop algorithm. It is
expressed in steps of 0,1 dB.
• qscdma_pilot_seed: Is the seed for the PN sequence that generates the QS-CDMA pilot symbols as defined in
TS 102 721-4 [4]. To be applied by mobile terminals.
• qscdma_pilot_gain_factor: Is the gain (β) of the pilot channel used by QS-CDMA carrier as defined in
TS 102 721-4 [4]. To be applied by mobile terminals.
• pattern_advantage_bias: Estimated difference between the pattern advantages of the satellite transmitter and
receiver antenna over the coverage area. It is expressed in steps of 0,1 dB.
• CRC_32: This is a 32-bit field that contains the CRC value that gives a zero output of the registers in the
decoder defined in annex B of EN 300 468 [1] after processing the entire section.
5.2.2.2 QS-CDMA Dynamic Table (QSDT)
The syntax of QSDT is shown in Table 5.11. It shall be segmented in QS-CDMA Dynamic sections using the syntax
described in EN 300 468 [1]. Any sections forming part of a QSDT shall be transmitted in TS packets with a PID value
assigned in the PMT. The QS-CDMA Configuration Table (QSDT) contains dynamic information regarding return link
spots. This table shall be mapped to the real time transport channel of the FWD link radio interface.
ETSI
19 ETSI TS 102 721-6 V1.2.1 (2013-08)
Table 5.11: QS-CDMA Dynamic Table (QSDT)
Syntax No. of bits
Information
Reserved
Mnemonic
Information
(see note)
qscdma_dynamic_table () {
SI_provate_section_header () 64 -
nof_rl_spots 8 uimsbf
rl_spot_info_length 16 uimsbf
for (i=0; i rl_spot_id 8 uimsbf
nof_rl_slots 8 uimsbf
rl_slot_info_length
...