1、 ETSI TS 102 550 V1.1.1 (2006-11)Technical Specification Satellite Earth Stations and Systems (SES);Satellite Digital Radio (SDR) Systems;Outer Physical Layer of the Radio InterfaceETSI ETSI TS 102 550 V1.1.1 (2006-11) 2 Reference DTS/SES-00284 Keywords digital, layer 1, radio, satellite ETSI 650 Ro
2、ute 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 but non lucratif enregistre la Sous-Prfecture de Grasse (06) N 7803/88 Important notice Individual copies of the present document can be downloade
3、d 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 sha
4、ll 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 avail
5、able 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 c
6、opyright and the foregoing restriction extend to reproduction in all media. European Telecommunications Standards Institute 2006. All rights reserved. DECTTM, PLUGTESTSTM and UMTSTM are Trade Marks of ETSI registered for the benefit of its Members. TIPHONTMand the TIPHON logo are Trade Marks current
7、ly being registered by ETSI 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. ETSI ETSI TS 102 550 V1.1.1 (2006-11) 3 Contents Intellectual Property Rights4 Foreword.4 1 Scope 5 2 References 5 3 Symbols a
8、nd abbreviations.5 3.1 Symbols5 3.2 Abbreviations .5 3.3 Number format and transmission order5 3.4 SI-Prefix Notation 6 4 Outer physical layer6 4.1 Overview 6 4.2 Interfacing to SL (Service Layer).8 4.3 S-TS to OPL adaptation layer: S-TS encapsulation .8 4.3.1 PF infoword format for S-TS stream type
9、 0 (dummy packet) 9 4.3.2 PF infoword format for S-TS stream type 1 (transparent) 10 4.3.3 PF infoword format for S-TS stream type 2 (MPEG-TS).10 4.3.4 PF infoword format for S-TS stream type 3 (IP stream).11 4.4 PL FEC: turbo code13 4.4.1 Interface to OPL encapsulation.13 4.4.2 Turbo encoder.13 4.4
10、.3 Turbo code termination.16 4.4.4 Turbo Interleavers.17 4.4.5 Output of turbo encoder18 4.4.6 FEC Parameter signalling .18 4.4.7 FEC Parameters for the signalling pipe 19 4.5 Mixer 19 4.6 Segmenter and Slot demultiplexer20 4.7 Disperser.20 4.8 Collector.21 4.9 C-TS multiplexer22 4.10 Configuration
11、of the OPL.23 4.10.1 Signalling pipe23 4.10.1.1 Encoding and interleaving of signalling pipe23 4.10.1.2 SOF Preamble .23 4.10.1.3 Format of the signalling pipe infoword.24 4.10.2 Partitioning of the C-TS multiplex .27 4.10.3 S-TS schedule and slot allocation.28 4.10.4 S-TS re-scheduling and slot re-
12、allocation.28 4.10.5 Birth/death of S-TS.29 4.10.6 S-TS ID.29 4.10.7 Calculation of the disperser profile.29 4.10.8 Configuration of the tail pipe30 4.10.9 Pipe reconfiguration31 Annex A (informative): Time slicing can be achieved on two layers .34 Annex B (informative): Bibliography.35 History 36 E
13、TSI ETSI TS 102 550 V1.1.1 (2006-11) 4 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
14、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 ETS
15、I 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
16、 This Technical Specification (TS) has been produced by ETSI Technical Committee Satellite Earth Stations and Systems (SES). TC SES is producing standards and other deliverables for Satellite Digital Radio (SDR) systems. An SDR system enables broadcast to fixed and mobile receivers through satellite
17、s and complementary terrestrial transmitters. Functionalities, architecture and technologies of such systems are described in TR 102 525. Several existing and planned ETSI standards specify parts of the SDR system, with the aim of interoperable implementations. The physical layer of the radio interf
18、ace (air interface) is divided up into the outer physical layer, the inner physical layer with a single carrier transmission, and the inner physical layer with multiple carriers transmission. These parts can be used all together in SDR compliant equipment, or in conjunction with other existing and f
19、uture specifications. The present document specifies the outer physical layer. The inner physical layer with single carrier transmission is specified in TS 102 551-1, and with multiple carriers transmission in TS 102 551-2. ETSI ETSI TS 102 550 V1.1.1 (2006-11) 5 1 Scope The present document concern
20、s the radio interface of SDR broadcast receivers. It specifies the functionality of the outer physical layer. It allows implementing this part of the system in an interoperable way. 2 References Void. 3 Symbols and abbreviations 3.1 Symbols For the purposes of the present document, the following sym
21、bols apply: R Code rate 3.2 Abbreviations For the purposes of the present document, the following abbreviations apply: AWGN Additive White Gaussian Noise BCH Bose, Ray-Chaudhuri, Hocquenghem code CRC Cyclic Redundancy Checksum C-TS Channel Transport Stream CU Capacity Unit FEC Forward Error Correcti
22、on IP Internet Protocol IPL Inner Physical LayerIU Interleaving Unit LSB Least Significant Bit MPEG-TS MPEG Transport Stream MSB Most Significant Bit MTU Maximum Transfer Unit PF Physical layer FEC OPL Outer Physical Layer PFIW Physical Layer FEC Info Word PL Payload QoS Quality of Service RFU Reser
23、ved for Future Use SOF Start Of Frame S-TS Service-TransportStream TS ETSI Technical SpecificationVBR Variable Bit Rate WER Word Error Rate 3.3 Number format and transmission order Unless otherwise stated, all bit/symbol streams and values are transmitted with the following convention: In a stream,
24、bits/symbols with a lower index are transmitted temporally earlier than those with a higher index. A prefix of a block of bits/symbols is transmitted temporally first, whereas a suffix is transmitted temporally last. ETSI ETSI TS 102 550 V1.1.1 (2006-11) 6 Signed integer and signed fixed-point value
25、s are stored in twos complement format. If a value is represented by N bits, the Most Significant Bit (MSB), i.e. bit N-1, is transmitted temporally first followed by bits N-2 down to bit 0, the Least Significant Bit (LSB). This order is referred to as Big Endian. For Bytes, the MSB, bit 7, is trans
26、mitted temporally first and the LSB, bit 0, last. The format of integer and fix-point values are specified in the following way: the first letter is U for unsigned and S for signed values, the following value following that letter states the number of integer bits. In the case of fixed-point values,
27、 this value is followed by a dot “.“ and another value, which specifies the number of fractional bits. Examples: U8, S3.2. 3.4 SI-Prefix Notation The present document uses the prefix notation as defined by the “Systme International dUnits“, i.e. M (mega) represents 1 000 000 units, k (kilo) represen
28、ts 1 000 units and m (milli) represents 0,001 units. 4 Outer physical layer 4.1 Overview The functionality of the Outer Physical Layer (in the following denoted OPL) is to provide Forward Error Correction and time interleaving for resistance against a variety of transmission channel conditions. Diff
29、erent transport channels are used in the OPL to offer the requested performance for different types of services. These transport channels are called pipes in the scope of the present document. The OPL is configurable in terms of error protection, outage mitigation in case of signal losses, end-to-en
30、d delay, zapping time, payload throughput and receiver complexity. Multiple pipes can be used as described above. Each of them contains FEC, Mixer and Disperser. One special pipe exists whose functionality is to transmit all relevant parameters to decode the other pipes. The so-called signalling pip
31、e is always transmitted at the lowest coderate which is 1/5. The modulation of the signalling pipe is equal to the modulation of the data pipes. The general block diagram of the OPL functionality is given in Figure 1. ETSI ETSI TS 102 550 V1.1.1 (2006-11) 7 Figure 1: General overview of the OPL func
32、tionality ETSI ETSI TS 102 550 V1.1.1 (2006-11) 8 The processing, multiplexing and demultiplexing of the data in the OPL is displayed in Figure 2. Figure 2: Definition of the different blocks envolved in the OPL processing 4.2 Interfacing to SL (Service Layer) The interface to the service layer is t
33、he so-called Service-Transport Stream (S-TS). For the OPL, each S-TS source is the smallest granularity which can be processed independently. The interface may work synchronously or asynchronously. In the case of asynchronous interface, the PL must be able to accept at least the average data rate th
34、at is provided by the SL. Any data buffering shall be done inside the SL, such that no data from the S-TS is lost at this interface. When the PL requests new data for transmission, the SL can either provide the requested data to the PL or it can signal that no data is currently available. If no data
35、 is available for transmission, the PL instead transmits dummy data that is discarded in the receiver. Inside an S-TS, multiplexing and de-multiplexing of information shall be carried out by the service layer. Each pipe provides a different set of transmission parameters (e.g. FEC code rate and disp
36、erser profile), and achieves a different QoS in terms of protection against transmission errors and end-to-end delay. One pipe of the OPL may carry several S-TS, all with the same QoS parameters. If PL time slicing is used, each time slice is associated with one S-TS. The scheduling of the S-TS, i.e
37、. their start instants and lengths, inside a pipe can be adapted frequently (once per schedule/time slicing period). This opens the possibility of handling Variable Bit Rate (VBR) transmission. The maximum allowed payload throughput per S-TS is 3,2 Mbit/s (this corresponds to approximatively 8 to 10
38、 video services inside one S-TS). This is the throughput that the processing chain inside the receiver (e.g. the turbo decoder) must be able to handle at least. 4.3 S-TS to OPL adaptation layer: S-TS encapsulation The OPL is prepared to transport different types of S-TS, and a mixture of different S
39、-TS types may be transported simultaneously over one C-TS multiplex. ETSI ETSI TS 102 550 V1.1.1 (2006-11) 9 The following parameters have to be determined for each S-TS (for parameters, refer to signalling pipe in clause 4.10.1): S-TS ID: identifier for the transported S-TS, that is unique for each
40、 network operator (i.e. for each Operator_ID); observe that one S-TS may be transported over multiple instances of the PL and still have a single unique S-TS ID; this helps, for example, for diversity combining of one S-TS transmitted over satellite and simultaneously over terrestrial repeaters. Sev
41、eral rules apply for the S-TS: - S-TS ID 0 plays a special role: this is the Service Layer configuration S-TS (the SL can signal its own configuration via this S-TS). - An S-TS may be fed to several C-TS multiplexes. The S-TS IDs in all of these C-TS multiplexes is identical. - An S-TS may not be fe
42、d to several pipes inside the same C-TS multiplex. - S-TS IDs must be unique over the complete network of one operator except for S-TS ID 0 which is allowed on every C-TS multiplex. - S-TS with an identical Operator_ID and S-TS ID can always be diversity combined (except for S-TS ID 0). - The length
43、 of an S-TS can be configured in a granularity of one PL infoword per C-TS frame. Pipe number that this S-TS is transported over. Moreover, for the ensemble of S-TS contained inside a complete C-TS multiplex, the following parameters have to be fixed (for parameters, refer also to signalling pipe in
44、 clause 4.10.1): Operator_ ID: unique identifier for the network operator. Partitioning of the C-TS multiplex into pipes and scheduling of the S-TS inside the pipes, i.e. what is the data rate of one S-TS and when are the bursts of one S-TS transported. Each S-TS is partitioned into packets to match
45、 the length of the PL FEC information word (PF infoword). The packet size is individual for each type of S-TS. The OPL encapsulation inside the S-TS to OPL adaptation layer adapts the length of the S-TS packets to the PF infoword length by appending a suffix to the S-TS packet. Table 1 defines the S
46、-TS packet length and the suffix length for different S-TS types. Table 1: Defined S-TS type IDs S-TS Type S-TS Type ID S-TS payload packet Size in bytes Suffix length in bits Comment Dummy packet 0 0 26 Used for asynchronous SL/PL interface. Is discarded in receiver. Transparent 1 1 532 26 SL has t
47、o decide what to do with this data. MPEG-TS 2 1 504 250 Payload packet is 8 MPEG packets of 188 bytes each; additionally, a BCH code of 196 bits is applied. IP stream 3 1 504 250 MTU of IP = 4 095 bytes with 2 bytes additional header per packet. The detailed format for the different types of S-TS is
48、 given in the following clauses. 4.3.1 PF infoword format for S-TS stream type 0 (dummy packet) The format of the dummy packet is given in Table 2. The insertion of a dummy packet is performed if no data was available at the instant of processing the actual packet in the OPL. ETSI ETSI TS 102 550 V1
49、.1.1 (2006-11) 10Table 2: PF infoword format for S-TS stream type 0 (dummy packet) Start bit index Parameter Description Wordsize (bits) Format Comment 0 Dummy data To be filled with zeros 12 256 1 532U8 (1 532 bytes) 12 256 RFU 4 bits reserved for future use 4 U4 helps to bit-align the payload to byte boundaries 12 260 STS_ID S-TS ID 8 U8 can be chosen arbitrarily 12 268 STS_Stream_Type_ID S-TS stream type identifier 3 U3 Fixed to 0 for dummy packets 12 271 Encap_Ver Version number of the OPL encapsulation format 3 U3 Fixed to 0 12 274 HeaderCRC CRC ov
