ETSI ETS 300 635 ed.1 (1996-10)

Transmission and Multiplexing (TM); Synchronous Digital Hierarchy (SDH); Radio specific functional blocks for transmission of M x STM-N

DE/TM-04028

Prenos in multipleksiranje (TM) – Sinhrona digitalna hierarhija (SDH) – Radijsko specifični funkcijski bloki za prenos pri Mx STM-N

General Information

• Status: Published
• Publication Date: 23-Oct-1996
• Technical Committee: TM 4 - TM Fixed Radio Systems
• Current Stage: 12 - Completion
• Due Date: 08-Nov-1996
• Completion Date: 24-Oct-1996
• Ref Project: SIST ETS 300 635 E1:2003 - Transmission and Multiplexing (TM); Synchronous Digital Hierarchy (SDH); Radio specific functional blocks for transmission of M x STM-N

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ETS 300 635 E1:2003
01-december-2003
3UHQRVLQPXOWLSOHNVLUDQMH70±6LQKURQDGLJLWDOQDKLHUDUKLMD6'+±5DGLMVNR
VSHFLILþQLIXQNFLMVNLEORNL]DSUHQRVSUL0[6701
Transmission and Multiplexing (TM); Synchronous Digital Hierarchy (SDH); Radio
specific functional blocks for transmission of M x STM-N
Ta slovenski standard je istoveten z: ETS 300 635 Edition 1
ICS:
33.040.20 Prenosni sistem Transmission systems
SIST ETS 300 635 E1:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ETS 300 635 E1:2003

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SIST ETS 300 635 E1:2003
EUROPEAN ETS 300 635
TELECOMMUNICATION October 1996
STANDARD
Source: ETSI TC-TM Reference: DE/TM-04028
ICS: 33.040.20
Key words: SDH, radio, transmission
Transmission and Multiplexing (TM);
Synchronous Digital Hierarchy (SDH);
Radio specific functional blocks
for transmission of Mx STM-N
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE
Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: [e-mail]
Tel.: [phone] - Fax: [phone]
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 1996. All rights reserved.

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Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.

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Contents
Foreword .5
1 Scope .7
2 Normative references.7
3 Abbreviations.8
4 Generalized functional block diagram .9
4.1 SDH Radio Synchronous Physical Interface function (RSPI) .10
4.1.1 Signal flow from B to R.12
4.1.2 Signal flow from R to B.13
4.1.3 Application to the transmission of Mx STM-N .14
4.2 Radio OverHead Access (ROHA).14
4.3 Radio Protection Switch (RPS).15
4.3.1 Signal flow .17
4.3.2 Additional requirement on the signal flow from XT (tributary side) to XL
(line side).18
4.3.3 Additional requirement on the signal flow from XL (line side) to XT
(tributary side).18
4.3.4 Switching initiation criteria .19
4.3.4.1 Lockout .19
4.3.4.2 Forced switch.19
4.3.4.3 Autoswitch signal fail .19
4.3.4.4 Autoswitch HBER and LBER.20
4.3.4.5 Autoswitch EW .20
4.3.4.6 Manual switch.20
4.3.4.7 Exercise.20
4.3.5 Switching time .20
4.3.6 Switch restore.20
4.3.6.1 Forced restore .20
4.3.6.2 Automatic forced restore .21
4.3.6.3 Automatic switch restore .21
5 Requirement of Operation and Maintenance (O&M).21
5.1 RSPI requirements .21
5.2 RPS requirements .21
6 Performance monitoring.22
Annex A (informative): RPS practical implementations .23
A.1 Signal flow and main functionality .25
A.1.1 RPS type A (VC4 Path layer RPS).25
A.1.2 RPS type B (MS layer RPS).26
A.1.3 RPS type C (RS layer RPS).26
A.1.4 RPS type D (Physical layer RPS) .26
Annex B (informative): Example of ROHA SOH managing of 2 Mbit/s wayside traffic in the
regenerator sections.27
Annex C (informative): Description of the transport network architecture based on SDH DRRS .28
C.1 Basic concepts .28
C.2 Radio specific atomic functions.30

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C.2.1 RSPI related atomic functions. 30
C.2.2 RPS related atomic functions. 31
Annex D (informative): Bibliography . 35
History. 36

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ETS 300 635: October 1996
Foreword
This European Telecommunication Standard (ETS) was produced by the Transmission and Multiplexing
(TM) Technical Committee of the European Telecommunications Standards Institute (ETSI).
Transposition dates
Date of adoption of this ETS: 4 October 1996
Date of latest announcement of this ETS (doa): 31 January 1997
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 31 July 1997
Date of withdrawal of any conflicting National Standard (dow): 31 July 1997

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Blank page

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1 Scope
This European Telecommunication Standard (ETS) defines functional blocks specific to the Digital Radio
Relay System (DRRS) which uses the Synchronous Digital Hierarchy (SDH) for transmitting Mx STM-N
signals (where STM-N is Synchronous Transport Module-(level) N).
Considering that:
- ITU-T Recommendation G.783 [7] describes the characteristics of SDH equipment functional
blocks;
and that:
- ETS 300 417 [1] defines a library of basic building blocks and a set of rules, by which they may be
combined to describe an SDH equipment;
this ETS uses the methodology specified in ITU-T Recommendation G.783 [7], in order to give a generic
description of a SDH DRRS. However in informative annex C some functional description in
ETS 300 417 [1] style has been included in order to facilitate a future enhancement of radio specific
functionality description with this methodology.
This ETS defines:
- the functional blocks specific to SDH DRRS.
This ETS does not define:
- the information model for radio relay network elements;
- the protocol stack to be used for message communication;
- the network level management processes;
- the functional block already defined by ITU-T Recommendation G.783 [7] and ETS 300 417 [1];
- the radio specific management of performance monitoring requirements.
The equipment functionality is consistent with SDH multiplexing structure given in ETS 300 147 [15].
Equipment developed prior to this ETS may not comply in all details with this ETS.
2 Normative references
This ETS incorporates, by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications
apply to this ETS only when incorporated in it by amendment or revision. For undated references, the
latest edition of the publication referred to applies.
[1] ETS 300 417: "Transmission and Multiplexing (TM); Generic functional
requirements for Synchronous Digital Hierarchy (SDH) transmission
equipment".
[2] ETS 300 304 (1994): "Transmission and Multiplexing (TM); Synchronous Digital
Hierarchy (SDH) information model for the Network Element (NE) view".
[3] ITU-R Recommendation F.750: "Architectures and functional aspects of
radio-relay systems for SDH based networks".
[4] ITU-T Recommendation G.773: "Protocols suites for Q-interfaces for
management of transmission systems".
[5] ITU-T Recommendation G.781: "Structure of Recommendations on equipment
for the Synchronous Digital Hierarchy (SDH)".

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[6] ITU-T Recommendation G.782: "Types and general characteristics of
Synchronous Digital Hierarchy (SDH) equipment".
[7] ITU-T Recommendation G.783: "Characteristics of Synchronous Digital
Hierarchy (SDH) equipment functional blocks".
[8] ITU-T Recommendation G.784: "Synchronous Digital Hierarchy (SDH)
management".
[9] ITU-T Recommendation G.803: "Architectures of transport networks based on
the Synchronous Digital Hierarchy (SDH)".
[10] ITU-T Recommendation G.831: "Management capabilities of transport networks
based on the Synchronous Digital Hierarchy (SDH)".
[11] ITU-T Recommendation M.3010: "Principles for a telecommunications
management network".
[12] ITU-T Recommendation M.60: "Maintenance Terminology and definitions".
[13] ITU-T Recommendation Q.811: "Lower layer Protocol profiles for the Q3
interface".
[14] ITU-T Recommendation Q.812: "Upper layer Protocols profile for the Q3
interface".
[15] ETS 300 147 (1995): "Transmission and Multiplexing (TM); Synchronous Digital
Hierarchy (SDH) Multiplexing structure".
[16] ITU-T Recommendation G.707: "Synchronous Digital Hierarchy bit rates".
[17] ITU-T Recommendation G.708: "Network node interface for the Synchronous
Digital Hierarchy".
[18] ITU-T Recommendation G.709: "Synchronous multiplexing structure".
3 Abbreviations
For the purposes of this ETS, the following abbreviations apply:
AIS Alarm Indication Signal
AP Access Point
ATPC Automatic Transmit Power Control
BER Bit Error Rate
CMIP Common Management Information Protocol
CMIS Common Management Information Service
CP Connection Point
CTP Connection Termination Point
DRRS Digital Radio Relay System
EW Early Warning
GTP Group Termination Point
HPA Higher order Path Adaptation
IF Intermediate Frequency: frequency(s) other than RF used for the purpose of
implementation depending functions (e.g. easier filtering)
IA Indirect Adapter
IOS Intra-Office Section
LOF Loss Of Frame
LPA Lower order Path Adaptation
MOC Managed Object Class
MSP Multiplex Section Protection
MSOH Multiplex Section OverHead
NE Network Element

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O&M Operations and Maintenance
OS Operation System
OSI Open System Interconnection
PDH Plesiochronous Digital Hierarchy
Pkg Packages
PI Physical Interface
RAPS Radio Automatic Protection Switch
RF Radio Frequency
RFCOH Radio Frame Complementary OverHead
ROHA Radio OverHead Access
RPI Radio (generic) Physical Interface
RPPI Radio Plesiochronous Physical Interface
RSPI Radio Synchronous Physical Interface
RPS Radio Protection Switching
RDN Relative Distinguished Name
RRR Radio Relay Regenerator
RRT Radio Relay Terminal
RS Regenerator Section
RSOH Regenerator Section OverHead
RST Regenerator Section Termination
SDH Synchronous Digital Hierarchy
SEMF Synchronous Equipment Management Function
SETS Synchronous Equipment Timing Source
SF Switch Failure
Snk Sink
SOH Section OverHead
SPI SDH Physical Interface
Src Source
STM-N Synchronous Transport Module (level) N
STM-RR Synchronous Transport Module for Sub-STM-1 Radio Relay
TMN Telecommunication Management Network
TP Termination Point
TTP Trail Termination Point
VC-n Virtual Container n
XPIC Cross Polar Interference Canceller
4 Generalized functional block diagram
Figure 1 is taken as a generalized block diagram for STM-N systems (in this figure Ux, Kx and Sx
interface numbering for radio specific blocks has been taken starting from 50 onward).
In figure 1 only the most common ITU-T Recommendation G.783 [7] defined functional blocks are
reported, together with the radio specific ones. Nevertheless other present or future defined functional
blocks may be implemented, if applicable, into SDH DRRS.
Additional description using ITU-T Recommendation G.803 [9] and ETS 300 417 [1] methodology is not in
the scope of this ETS, however some basic related concept may be found in annex C.

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U6
To
PDH
M
PPI
LPA
ROHA interfaces
OHA interfaces
G.703
K50 K51
S11 S10
S13
S52
OHA
T2 To U4 To To To U3 ROHA
To U5
U6
PDH
M L K J G
H
PPI LPA LPT LPC HPA HPT
U1 U6
U1 U2 U50
G.703
S11 S10 S9 S8 S7 S6
To U1 U2 To To To To To To To U2 U1 To K50
U50
A F
B C D E F E D C B R
HPC
SPI RST MST MSP MSA MSA MSP MST RST RSPI
STM-N
RF
S1 S2 S3 S14 S4 S5 S14 S2 S50
T1 N P S4 S3 P N T1
Y
Y
S1 Sn
K51
T2 To
To T1
Ext.
T3
SETPI
SETS XT XL
SEMF
RPS
Synchr.
note
T4
V
S12
S15
S51
P
MCF
N
f
Q
U50: Reference point for Radio Frame Complementary OverHead (RFCOH) bytes access
(insertion/extraction);
K50: Media specific or RFCOH bytes (whichever is applicable) interface for Radio
Synchronous Physical Interface (RSPI) usage;
K51: Media specific or RFCOH bytes (whichever is applicable) interface for Radio Protection
Switching (RPS) usage;
XT: RPS Reference point (Tributary side);
XL: RPS Reference point (Line side);
Other references: see ITU-T Recommendations G.782 [6] and G.783 [7].
NOTE: The RPS functional block comprises a connection type function which, for an implementation
dependent purpose, can be inserted in between any other functional block to perform specific
(n + m) line protection for the radio section. It has the same "X" input/output interfaces which
are always compatible with any interface where it may be inserted, namely reference points B,
C, D, E or F, however it should be noted that, when looked from the point of view of
ETS 300 417 [1] methodology, RPS placed in different network layer will result in different
functionality (see informative annex A for details).
Figure 1: Generalized SDH-DRRS logical and functional block diagram
4.1 SDH Radio Synchronous Physical Interface function (RSPI)
The RSPI function provides the interface between the radio physical medium at reference point R and the
Regenerator Section Termination (RST) function at reference point B.
Data at R is a Radio Frequency (RF) signal containing an STM-N signal with non-standardized use of
Section Overhead (SOH) media dependent bytes (provided by ITU-T Recommendations G.707 [16] and
G.708 [17]) and (if used) an additional arbitrary RFCOH. Therefore, in accordance with
ITU-R Recommendation F.750 [3], mid-air interconnectivity between transmitter and receiver of different
vendors is not required.
The information flows associated with the RSPI function are described with reference to figure 2.
This functional block is, therefore, expanded in figure 3.

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K50 is an interface for any radio specific control and monitoring use (e.g. Automatic Transmit Power
Control (ATPC) making use of the media specific bytes of Regenerator Section OverHead (RSOH) or of
RFCOH extracted through reference points U1 or U50 respectively and made available by the Radio
OverHead Access (ROHA) functional block. The possible functional modelling with ETS 300 417[1]
methodology of the RSOH access for K50 interface is shown in figure C5 annex C (informative).
K50 U50
Reference point B Reference point R
RF Out
Data
Timing
RSPI
Receive loss of Signal
Data
Timing
RF In
S50 T1
Figure 2: RSPI functional block
The RSPI functions are subdivided into transmit (source) and receive (sink) functions; a second level of
decomposition refinement is the splitting of the transmit and receive functions into two smaller sub blocks,
as shown in figure 3. These are:
- transmit function: modulation function;
TX function;
- receive function: demodulation function;
RX function.
These functions are described as follows:
- the modulation function performs all the processing needed to transfer the STM-N data signal at
reference point B into a suitable Intermediate Frequency (IF) or RF signal (whichever is applicable),
including scrambling (additional to that provided by RST function) and optionally, channel-coding
and RFCOH insertion;
- the TX function represents the process of power amplifying the signal, coming from the modulation
function, filtering and optionally, up converting from the modulation function for presentation at
reference point R;
- the RX function represents any signal processing between the receiver input at reference point R,
and the demodulation function input. The signal processing performed by the RX function also
includes any diversity of reception arrangement, which would be represented as an equipment
redundancy by multiple receivers (and if required demodulators) within a single receive function;
- the demodulation function represents any process (including propagation countermeasures e.g.
equalizer and Cross Polar Interference Canceller (XPIC)) of converting an IF or RF signal
(whichever is applicable), into a fully formatted STM-N data signal for presentation at reference
point B. The demodulation process includes the functions of filtering, timing recovery and
descrambling, and may optionally include RFCOH extraction and propagation countermeasures,
e.g. equalizer, XPIC, error correction.

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K50
U50
RSPI
Transmit Function
Modulation TX
Function Function
lossOfSignal(mod) modulationFail txLOS txFail
B R
Receive Function
Demodulation RX
Function Function
demodulationFail demLOS rxFail lossOfSignal(rx)
S50 T1
Figure 3: RSPI functional block (detail)
Given that the RSPI includes modulation and demodulation functions, it performs a regeneration of the
signal in the DRRS repeater. As a consequence, when the network provider requires that radio repeaters
behaved and were managed like SDH regenerators, the RSPI function shall be always used in conjunction
with a Regenerator Section Termination (RST) function in order to perform SDH functionalities; the
opposite case is not in the scope of this ETS.
4.1.1 Signal flow from B to R
Data flow at B is the fully formatted STM-N data as specified in ITU-T Recommendations G.707 [16],
G.708 [17] and G.709 [18]. Data is presented together with associated timing at B by the RST function.
The RSPI function multiplexes these data together with the RFCOH (if used) and adapts them for
transmission over the RF medium (by means of a suitable modulation format, carrier frequency and output
power) and presents it at R.
Data for inclusion in RFCOH (if used) are inserted at reference point U50.
Radio specific managing data (e.g. ATPC increase/decrease power request from the far end receiver
function to control the local transmitter function) will be shown at K50 from functional block ROHA, which
has provided proper extraction from the media specific byte of RSOH or from RFCOH through reference
point U1 or U50 respectively (see ROHA functional block description).
Indications related to the physical status of the interface shall be reported at S50 to the Synchronous
Equipment Management Function (SEMF) functional block.

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Requirements of Operation and Maintenance (O&M) are:
lossOfSignal(mod): This indication shall indicate a loss of the incoming data for the modulation function.
The indication is used in case of split indoor/outdoor RSPI functions, it is therefore optional.
modulationFail: This indication shall report the internal failures of the modulation function affecting the
modulated signal and the loss of incoming data to the modulation function.
txFail: This indication shall indicate a failed transmitted signal caused by internal failure of the transmit
function.
txLOS: This indication shall indicate a loss of the incoming signal for the transmitting function (TX).
When the distinction between txFail and txLOS can not be carried out with a sufficient degree of
confidence, the use of txFail indication shall be preferred, therefore this indication is optional.
ATPC Status: Returns the ATPC status of the TX function as "ATPC implemented/not implemented" and
"ATPC enabled/disabled".
ATPC Enable: Command to enable/disable ATPC for the TX function, provided when ATPC is
implemented.
Transmitted level request: Returns the monitored transmitter output power at reference point R for the
TX function.
4.1.2 Signal flow from R to B
The RF signal received at R may be either a single signal or a signal doubled (or multiplied) for a space
(or/and angle) diversity of protection against adverse propagation phenomena.
The RF signal at reference point R contains STM-N signal together with an arbitrary RFCOH (if used).
The RSPI function recovers data and associated timing at reference point B from the RF signal. The
recovered timing is also made available at reference point T1 to the Synchronous Equipment Timing
Source (SETS) for the purpose of synchronizing the synchronous equipment reference clock if selected.
The RFCOH, if present, is made available at reference point U50.
When the proper receiver thresholds are activated (e.g. by receiver power level or by error correction
activity), radio specific managing data (e.g. ATPC increase/decrease power request from the local
receiver function to be sent to the far end transmitter function or early warning switching request to the
local Radio Protection Switching (RPS) or to be forwarded from a regenerative repeater to the next one)
will be shown at K50 to functional block ROHA, which will provide for proper insertion in the media specific
byte of RSOH or in RFCOH through reference points U1 or U50 respectively.
If the signal fails at reference point R or the input signal to the demodulation function fails, then the receive
Loss of Signal (LOS) condition is generated and passed to reference point S50 and to the RST function at
B. The signal at reference point R is considered to have failed when none of the receivers contained by a
single receive function are able to present a signal of sufficiently high quality to enable the demodulation
function to distinguish and recover the transmitted symbols.
Requirements of O&M are:
lossOfSignal(rx): This indication shall report a loss of the incoming signal at reference point R for the RX
function. When the distinction between rxFail and lossOfSignal(rx) can not be carried out with a sufficient
degree of confidence, the use of rxFail indication shall be preferred, therefore this indication is optional.
rxFail: This indication shall report the internal failures of the RX function affecting the received signal.
demLOS: This indication shall indicate a loss of the incoming data for the demodulation function.
When the distinction between demodulationFail and demLOS can not be carried out with a sufficient
degree of confidence, the use of demodulationFail indication shall be preferred, therefore this indication is
optional.

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demodulationFail: This indication shall report the internal failures of the demodulation function affecting
the demodulated signal.
The following primitives are also optionally envisaged to be accessed via reference point S50 for
maintenance operation purposes:
receivedLevelRequest: Returns the received power level at reference point R detected by the
RX function. When a single receive function comprises more than one receiver for diversity redundancy,
receivedLevelRequest will address each receiver in order to return its detected received power level.
4.1.3 Application to the transmission of Mx STM-N
The case of systems carrying more than one STM-N either by a multi-carrier technique or by single carrier
with a bit rate Mx STM-N, will be represented from the functional point of view by duplicating the RSPI
functional block up to M times. It should be noted however that this does not imply any relationship with
physical hardware implementation.
4.2 Radio OverHead Access (ROHA)
The description of this function makes reference to figure 4a.
ROHA interfaces
K50 K51
S52
ROHA
U1 U2 U50
Figure 4a: ROHA functional block
This function gives external access to RFCOH bytes (from reference point U51) and to the SOH unused
bytes (i.e. bytes reserved for future international standardization, media specific bytes and, in agreement
with the network provider, national use bytes available from reference points U1 and U2) in order to
provide radio specific controls and monitoring interfaces and wayside traffic.
Moreover, it supplies transmission interfaces K50 and K51 to functional blocks RSPI and RPS,
respectively, allowing the required information exchange between corresponding radio terminals or
regenerators for managing specific functions (e.g. ATPC) and the non-standardized switching control
protocol to operate the RPS in the n + m configuration.
Data at K50 and K51 interfaces will be inserted/extracted into/from the dedicated media specific bytes of
RSOH (available at reference point U1) or of RFCOH (available at reference point U50).
The ROHA function can provide 1 + 1 protection for the above mentioned signals.
The ROHA function recovers early warning switching requests of any foreseen threshold coming through
the relevant bytes at reference points U1 or U50. It subsequently processes this information with the
equivalent bytes coming through reference point K50 from the local receiver and makes the results
available for further forwarding to the next repeater (through the relevant bytes at U1 or U50) of the
regenerative repeaters or, to functional block RPS (through reference point S52) in the radio terminals
(see figure 4b).
When in the regenerator sections, wayside traffic signal up to 2 Mbit/s is provided on the SOH
(as foreseen by ITU-R Recommendation 750 [3]), a possible functionality for ROHA is reported in the
informative annex A.

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Other indications that may be reported at reference point S52 are:
lossOfSignal#(in): This indication is optional and reports the loss of input signal (TX side) for
service/wayside channel number #.
EW nth threshold (Note)
EW 2nd threshold
EW 1st threshold
EW 1st
threshold
EW 1st
U1 or U51
threshold
EW 2nd
U1 or processing
threshold
S52
U50 EW 2nd
S52
(remote EW)
threshold
EW nth processing
threshold
EW nth
(Note)
threshold
(Note)
EW 1st
threshold
K50
EW 2nd
K50
proce
...