1、 STDoITU-T RECMN J-150-ENGL 1998 m 48b259L Ob53772 3TB m INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUN KATION STANDARDIZATION SECTOR OF ITU J.150 (03/98) SERIES J: TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS Digital television distribution through local subscrib
2、er networks Operational functionalities for the delivery of digital multiprogramme television, sound and data services through multichannel, multipoint distribution systems (MMDS) ITU-T Recommendation J.150 (Previously CCITT Recommendation) ITU-T J-SERIES RECOMMENDATIONS TRANSMISSION OF TELEVISION,
3、SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS General Recommendations General specifications for analogue sound-programme transmission Performance characteristics of analogue sound-programme circuits Equipment and lines used for analogue sound-programme circuits Digital encoders for analogue sound-pr
4、ogramme signals Digital transmission of sound-programme signals Circuits for analogue television transmission Analogue television transmission over metallic lines and interconnection with radio-relay links Digital transmission of television signals Ancillary digital services for television transmiss
5、ion Operational requirements and methods for television transmission Interactive systems for digital television distribution Transport of MPEG-2 signals on packetised networks J. 1-J.9 J.10-J.19 J. 20-J. 29 J .30-J.39 J.40-J .49 J.50-J.59 J.60-J.69 J.70-J.79 J .8O-J.89 J .90-J .99 J. 100-J. 109 J. 1
6、 1 O-J. 129 J. 130-5.1 39 Measurement of the quality of service J. 1 40-J. 1 49 For further details, please refer to ITU-T List of Recommendations. STD.ITU-T RECMN J-1.50-ENGL 3998 4b2591 Ob53774 370 m ITU-T RECOMMENDATION J.150 OPERATIONAL FUNCTIONALITIES FOR THE DELIVERY OF DIGITAL MULTIPROGRAMME
7、TELEVISION, SOUND AND DATA SERVICES THROUGH MULTICHANNEL, MULTIPOINT DISTRIBUTION SYSTEMS (MMDS) Source ITU-T Recommendation J. 150 was prepared by ITU-T Study Group 9 (1997-2000) and was approved under the WTSC Resolution No. 1 procedure on the 18th of March 1998. Recommendation J.150 (03/98) i FOR
8、EWORD ITU (International Telecommunication Union) is the United Nations Specialized Agency in the field of telecommuni- cations. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the ITU. The IT-T is responsible for studying technical, operating and tariff questions an
9、d issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Conference (WTSC), which meets every four years, establishes the topics for study by the IT-T Study Groups which, in their turn, produce Recommendations
10、 on these topics. The approval of Recommendations by the Members of the ITU-T is covered by the procedure laid down in WTSC Resolution No. 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE
11、 In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS The ITU draws attention to the possibility that the practice or implementation of this Recommendation m
12、ay involve the use of a claimed Intellectual Properiy Right. The ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval o
13、f this Recommendation, the ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB pa
14、tent database. O ITU 1998 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. 11 Recommendation 5.150 (03/98) CONTENTS 1 Introduction 2
15、Scope 3 References 4 Definitions 5 Abbreviations and acronyms Annex A - Digital multiprogramme MMDS System A A . 1 Introduction . A.2 MMDS system concept . A.3 MPEG-2 transport layer A.4 Framing structure AS Channel coding . A.6 Byte-to-symbol mapping . A.7 Modulation A.8 Baseband filtering characte
16、ristics Annex B - Digital multiprogramme MMDS System B . Annex C - Digital multiprogramme MMDS System C . C . 1 Introduction . C.2 MMDS System C concept . C.3 MPEG-2 transport layer C.4 Framing structure C.5 Channel coding . C.6 Modulation Annex D - Digital multiprogramme MMDS architecture System D
17、. D.l Introduction . D.2 MMDS VSB system concept Recommendation J.150 (03/98) 1 1 1 1 2 2 2 2 4 4 4 4 4 4 5 5 5 5 6 6 6 6 7 7 7 . 111 Recommendation J.150 OPERATIONAL FUNCTIONALITIES FOR THE DELIVERY OF DIGITAL MULTIPROGRAMME TELEVISION, SOUND AND DATA SERVICES THROUGH MULTICHANNEL, MULTIPOINT DISTR
18、IBUTION SYSTEMS (MMDS) (Geneva, 1998) 1 Introduction This Recommendation extends the cable television network architectural principles to Multichannel, Multipoint Distribution systems (MMDS) which use radio waves at microwave frequencies, of the order of a several GHz. Recommendation J.83 is incorpo
19、rated by direct reference. 2 Scope The scope of this Recommendation covers the operational functionalities for digital (multiprogramme) signals distributed by MMDS systems, used as extensions or alternatives to CATV networks, possibly in frequency division multiplex with existing analogue signals. D
20、etailed specifications are contained in Annexes A, B, C and D. Annex A is based on work done in Europe and should provide a suitable basis for future developments. Annex B is still under study. Annex C is based on work done in Japan and should provide a suitable basis for future developments. Annex
21、D is based on VSB modulation scheme and on work done in North America. It should provide a suitable basis for future developments. It should be noted that this Recommendation deals with downstream signal delivery only; the needs for interactive services requiring both downstream and upstream (return
22、) channels are beyond the scope of this Recommendation. 3 References The following ITU-T Recommendations, and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Re
23、commendations and other references are subject to revision; all users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is re
24、gularly published. Pl ITU-T Recommendation J. 83 (1 997), Digital multi-programme systems for television, sound and data services for cable distribution. Pl Recommendation ITU-R F.755-1 (1 993), Point-to-multipoint systems used in the fuced service. 31 Recommendation ITU-R BO. 121 1 (1 995), Digital
25、 multi-programme emission systems for television, sound and data services for satellites operating in the 11/12 GHz fiequency range. 4 Definitions This Recommendation defines the following term: 4.1 byte: A group of eight bits. Recommendation J.150 (03/98) 1 5 Abbreviations and acronyms This Recomme
26、ndation uses the following abbreviations: BB CATV C/N FEC 1, Q MMDS MPEG MUX QAM QPSK RF VSB Baseband Cable Television Carrier-to-Noise ratio Forward Error Correction In-phase, Quadrature phase components of the modulated signal Multichannel, Multipoint Distribution System Moving Pictures Experts Gr
27、oup Multiplex Quadrature Amplitude Modulation Quaternary Phase Shift Keying Radio Frequency Vestigial Sideband Annex A Digital multiprogramme MMDS System A A.l Introduction This Annex describes a transmission system known as System A for digital multiprogramme television distribution by MMDS operati
28、ng below 10 GHz. It is based on the System A of Recommendation 5.83. It uses QAM modulation and allows for 16, 32 and 64 constellation points. A.2 MMDS system concept The MMDS system shall be defined as the functional block of equipment performing the adaptation of the baseband TV signals to the MMD
29、S channel characteristics (see Figure A.l). At the transmitter site, the following TV baseband signal sources can be considered: - satellite signal(s); - cable signal(s); - contribution link(s); - local program source(s). The following processes shall be applied as shown in Figure A. 1 : - baseband
30、interfacing and synchronization; - - Reed-Solomon encoding; - convolutional interleaving; - byte to m-tuple conversion; - differential encoding. synchronization 1 inversion and randomization; 2 Recommendation J.150 (03198) STDoITU-T RECMN J-150-ENGL 1778 W u) c. .- ES ES . 4 4 4 4 4 “4 . - U 4862573
31、 Ob53779 752 U 4 4 “-1- “S -I al z? LUI I I l I I I I I I I l I u c Y O m P 3 a 2 o O w I o * $ $ Ei a rA a E E c O rA a * .3 rA M E * a U a i .- .- .u e co M C .- c c) .C E c m i a .L e +-. I v * e o I E a c O co i M I m E 1- u O .o cd P, a U e I - I a c) u O iti c, 2 Q) i M a k .- N Recommendation
32、 J.150 (03/98) 3 All these functions are identical to those defined in Annex AlJ.83. - Baseband shaping Similar to the 5.83 System A, this unit performs mapping from differentially encoded m-tuples to I and Q signals and a square-root raised cosine filtering of the I and Q signals prior to QAM modul
33、ation. - QAM modulation and physical interface Similar to the J.83 System A, this unit performs QAM modulation. It is followed by interfacing the QAM modulated signal to the radio-frequency MMDS channel. The MMDS System A receiver shall perform the inverse signal processing, as described for the mod
34、ulation process above, in order to recover the baseband signal. A.3 MPEG-2 transport layer The MPEG-2 transport layer shall be identical to the one defined in J.83 System A. A.4 Framing structure The framing structure shall be identical to the one defined in 5.83 System A. AS Channel coding The chan
35、nel coding shall be identical to the one defined in J.83 System A. A.6 Byte-to-symbol mapping The byte-to-symbol mapping shall be identical to the one defined in J.83 System A. A.7 Modulation 5.83 System A defined modulations for cable networks. They are also valid for the MMDS channels. The modulat
36、ions of System A shall be identical to the ones defined in J.83 System A. A.8 Baseband filtering characteristics The baseband filtering characteristics shall be identical to the ones defined in J.83 System A. 4 Recommendation 5.150 (03/98) STD-ITU-T RECMN J-3.50-ENGL - 1998 Waveform 64-QAM Error cor
37、rection Interieaver Reed-Solomon (1 2 bytes) - - shaping - modulation (a= 0.13) (Note) (204,188) m Error correction (12 bytes) Reed-Solomon down Waveform (Note) (a = 0.13) - De-interleaver converter 64-QAM demodulation - shaping - (204,188) Li862591 Data Baseband - - Clock Energy dispersal - removal
38、 IIF Ob51781 300 9 Annex B Digital multiprogramme MMDS System B System B of Recommendation J.83 has at the present time no companion MMDS system. Annex C Digital multiprogramme MMDS System C C.l Introduction This Annex describes a transmission system for digital multiprogramme television distributio
39、n known as MMDS. MMDS System C uses a frequency band up to several GHz. The system is based on Annex C/J.83, and this Recommendation depicts digital encoding and modulation before the MMDS transmitter and digital demodulation and decoding after the MMDS receiver that contains a down converter. C.2 M
40、MDS System C concept A configuration of MMDS System C is shown in Figure C.1. Considering service data quality and service range, Forward Error Correction (FEC) and quadrature amplitude modulation (64-QAM) technologies are introduced. In a higher frequency usage, other modulation methods should be a
41、pplied if the system could not meet the MMDS system requirement. Transmitter side Baseband Energy dispersal To MMDS transmitter - NOTE - In higher frequency ranges, other modulation methods should be applied to meet the MMDS system requirement. Figure C.1/5.150 - MMDS System C configuration Recommen
42、dation J.150 (03/98) 5 STD-ITU-T RECMN J=LSO-ENGL 1998 m 4862593 Ob53782 247 m C.2.1 Transmitter side The baseband signal for MMDS transmission is a source of MPEG-2 ISS-byte packets. The MPEG-2 packets are processed by: 1) data randomizer; 2) Reed-Solomon encoder; 3) data interleaver; 4) differenti
43、al encoder; 5) 64-QAM modulator. C.2.2 Receiving side After the low noise amplifier and down converter, the receiving side of MMDS System C is configured as the inverse function of the transmitter side: QAM demodulator, differential decoder, symbol-to-byte mapping, de-interleaver, Reed-Solomon decod
44、er and data de-randomizer. C.3 MPEG-2 transport layer The MPEG-2 transport layer should be compliant with Annex UJ.83. C.4 Framing structure The framing structure should be compliant with Annex UJ.83. C.5 Channel coding The channel coding should be compliant with Annex UJ.83. C.5.1 Randomization The
45、 randomization should be compliant with Annex UJ.83. C.5.2 Reed-Solomon coding The Reed-Solomon coding should be compliant with Annex UJ.83. C.5.3 Convolutional interleaving The convolutional interleaving should be compliant with Annex UJ.83. C.6 Modulation C.6.1 Byte-to-symbol mapping The byte-to-s
46、ymbol mapping should be compliant with Annex UJ.83. C.6.2 Differential encoding The differential encoding should be compliant with Annex UJ.83. C.6.3 64-QAM constellation The 64-QAM constellation should be compliant with Annex UJ.83. Other modulation methods are under study for use at a fiequency,ra
47、nge higher than the one considered in this Recommendation. C.6.4 Roll-off factor The roll-off factor should be compliant with Annex UJ.83. C.6.5 Baseband filter characteristics The baseband filter characteristics should be compliant with Annex UJ.83. 6 Recommendation 5.150 (03/98) STD*ITU-T RECMN J-
48、150-ENGL 1998 Y862591 Ob51783 183 Annex D Digital multiprogramme MMDS architecture System D D.l Introduction This Annex describes the head-end processing and equipment configuration suitable for digital MMDS based on MPEG-2 transport multiplexing by the use of a chosen mode of the Vestigial Sideband
49、 (VSB) digital transmission system as defined in Annex D/J.83. D.2 MMDS VSB system concept D.2.1 Head-end A configuration of head-end equipment suitable for digital multiprogramme systems is shown in Figure D. 1. As shown, television programming is supplied by satellite signals, terrestrial broadcast signals - local and distant, all of which may be analogue or digital. The satellite signal, when digital, with appropriate demodulator and interface circuitry, is a source of MPEG-2 188-byte packets. The MPEG-2 188-byte packet source(s) are processed by: 1) data rand
