1、Rec. ITU-R B0.1130-4 1 RECOMMENDATION ITU-R BO.1130-4 Systems for digital satellite broadcasting to vehicular, portable and fixed receivers in the bands allocated to BSS (sound) in the frequency range 1 400-2 700 MHz (Question ITU-R 93/10) (1 994- 1995- 1999-2000-200 1) The IT Radiocommunication Ass
2、embly, considering a) that there is an increasing interest worldwide for digital sound broadcasting to vehicular, portable and fixed receivers in the broadcasting-satellite service (BSS) (sound) bands allocated at the World Administrative Radio Conference for Dealing with Frequency Allocations in Ce
3、rtain Parts of the Spectrum (Malaga-Torremolinos, 1 992) (WARC-92), and that several satellite-based digital sound broadcasting services for national and supra-national coverage are being considered; b) that the ITU-R has already adopted Recommendations ITU-R BS.774 and ITU-R B0.789 to indicate the
4、necessary technical and operating characteristics for digital sound broadcasting systems to vehicular, portable and fixed receivers for terrestrial and satellite delivery, respectively; c) that to conform with the requirements of Resolution ITU-R 1, where Recommendations provide information on multi
5、ple systems, an evaluation of the systems should be undertaken and the results of that evaluation should be included in the Recommendation; d) documented in the ITU-R; that all five recommended systems (Digital Systems A, B, Ds, DH and E) are sufficiently e) have been documented in the ITU-R; that t
6、hese five systems have been field-tested sufficiently, and that the results of these tests 0 that Digital System A, described in Annex 1, is the recommended standard for terrestrial digital sound broadcasting to vehicular, portable and fixed receivers in the frequency bands allocated to sound broadc
7、asting above 30 MHz as specified in Recommendation ITU-R BS. 1 1 14; g) that Digital System DH, described in Annex 5, is being considered for a draft new Recommendation by Radiocommunication Study Group 6 for the terrestrial component of hybrid satellite/terrestrial digital sound broadcasting to veh
8、icular, portable and fured receivers in the frequency band 1452-1 492 MHz allocated to sound broadcasting; h) that a standardization process in Europe has resulted in the adoption of Digital SystemA (Eureka 147 as a European Telecommunications Standard Institute (ETSI) Standard ETS 300 401) for BSS
9、(sound)/broadcasting service (BS) (sound) to vehicular, portable and fixed receivers; 3 2 Rec. ITU-R B0.1130-4 j) that Resolution 1, digital sound broadcasting, of the 8th World Conference of Broadcasting Unions (Barbados, 24-25 April 1995) stated that continuing efforts should be made to see if a u
10、nique worldwide standard is achievable, and if not achievable, that maximum commonality of source coding, transport structure, channel coding and frequency band should be encouraged, noting that summaries of Digital Systems A, B, Ds, DH and E are presented in Annex 1; that the full system descriptio
11、ns for Digital Systems A, B, Ds, DH and E are given in a) b) Annexes 2,3,4,5 and 6, recommends 1 that Digital Systems A, B, Ds, DH and E, as described in Annexes I through 6, be used for satellite digital sound broadcasting services to vehicular, portable and fixed receivers in the frequency range I
12、 400-2 700 MHz; 2 that administrations that wish to implement BSS (sound) meeting some or all of the requirements as stated in Recommendation ITU-R B0.789, should use Table 1 to evaluate the respective merits of Digital Systems A, B, Ds, DH and E. NOTE 1 - Digital System C is for terrestrial use onl
13、y. 4 Rec. ITU-R B0.1130-4 3 W e Q - o .m E w E c h r/i d c .C .C .* M L Ei v1 2 rn h 5 4 Rec. ITU-R B0.1130-4 w 8 x ai II) c c) .I .I M Ei a“ c) B x II) o M I U .I .I Ei a“ c s x m ai M I c) .I E ep 8 x II) ai M - c) .I E a U 3 rn h II) (o M I c) .I .I Ei 6 w c) B Wl h CA I M I c) .- .I fi a“ c) B m
14、 h CA I M I c) .I E m c) B x CA I M I ci .I a 4 f B x m I M - CI .I .- Ei - Rec. ITU-R B0.1130-4 5 w I I I I 7 6 Rec. ITU-R B0.1130-4 w U 3 v h v) o M m Y .I E 3 Y s A v) m o Y .I .I M n a“ U s A E v) - m c .I M U : v) h VI o M I U .I E a A 3 E U s tA m .I M I I l I I I I I I 8 Rec. ITU-R B0.1130-4
15、7 U E B m v) x v1 - U M E 9 8 Rec. ITU-R B0.1130-4 hi 10 .e 2 3 c 3 E! I, hi Rec. ITU-R B0.1130-4 9 11 10 Rec. ITU-R B0.1130-4 1 ANNEX 1 Annex description of digital BSS (sound) systems Summary of Digital System A Digital System A, also known as the Eureka 147 DAB (digital audio broadcasting) system
16、, has been developed for both satellite and terrestrial broadcasting applications in order to allow a common low-cost receiver to be used. The system has been designed to provide vehicular, portable and fixed reception with low gain omnidirectional receive antennas located at 1.5 m above ground. Dig
17、ital System A allows for complementary use of satellite and terrestrial broadcast transmitters resulting in better spectrum efficiency and higher service availability in all receiving situations. It especially offers improved performance in multipath and shadowing environments which are typical of u
18、rban reception conditions, and the required satellite transponder power can be reduced by the use of on-channel terrestrial repeaters to serve as “gap-fillers“. Digital System A is capable of offering various levels of sound quality up to high-quality sound comparable to that obtained from consumer
19、digital recorded media. It can also offer various data services and different levels of conditional access and the capability of dynamically re-arranging the various services contained in the multiplex. 2 Summary of Digital System B Since available transponder power is at a premium on communications
20、 satellites, Digital System B, originally proposed by Voice of AmericdJet Propulsion Laboratory (VONJPL), was designed to provide maximum efficiency on board a communications satellite. Use is made of QPSK coherent demodulation. Appropriate levels of error correction are included. Since complementar
21、y terrestrial use requires significant multipath rejection, an adaptive equaliser technique was designed to permit Digital System B to be a complete satellite/terrestrial broadcast delivery mechanism. Receiver cost is expected to be relatively low because the modulation methods and other aspects of
22、the overall design are relatively simple. The systems current status is that it is a hardware prototype engineering model. 3 Summary of Digital System Ds Digital System Ds, also known as the Worldspace system, is primarily designed to provide satellite digital audio and data broadcasting for fixed a
23、nd portable reception. It has been designed to optimize performance for satellite service delivery in the 1452-1 492 MHz band. This is achieved through the use of coherent QPSK demodulation with concatenated block and convolutional error correcting coding, and linear amplification. The choice of TDW
24、QPSK modulation allows for enhanced coverage for a given satellite transponder power. Digital System Ds provides for a flexible multiplex of digitized audio sources to be modulated onto a downlink TDM carrier. The Digital System Ds receiver uses state-of-the-art microwave and digital large-scale int
25、egrated circuit technology with the primary objective of achieving low-cost production and high-quality performance. Work is also proceeding on the development of techniques to allow hybrid satelliteherrestrial broadcasting systems using Digital System Ds. 12 Rec. ITU-R B0.1130-4 11 4 Summary of Dig
26、ital System DH Digital System DH, also known as the hybrid satelliteterrestrial Worldspace system, is designed to provide satellite digital audio and data broadcasting for vehicular, fixed and portable reception by inexpensive common receivers. The satellite delivery component of Digital System DH i
27、s based on the same broadcast channel transport used in Digital System Ds but with several significant enhancements designed to improve Los reception in areas partially shadowed by trees. These enhancements include fast QPSK phase ambiguity recovery, early/late time diversity and maximum likelihood
28、combination of early/late time diversity signals. It extends the system structure of Digital System Ds by adding the terrestrial delivery system component based on MCM. MCM is a multipath-resistant orthogonal frequency division multiplex technique that has gained wide acceptance for pervasive mobile
29、 reception from terrestrial emitters. The MCM extension improves upon the techniques which are common in systems such as Digital System A, which is one standard utilized for terrestrial digital audio broadcast services. MCM utilizes multiple frequencies to avoid frequency selective fades resulting f
30、rom channel delay spread. 5 Summary of Digital System E Digital System E, also known as the ARIB (Association of Radio Industries and Businesses) system, is designed to provide satellite and complementary terrestrial on-channel repeater services for high-quality audio and multimedia data for vehicul
31、ar, portable and fixed reception. It has been designed to optimize performance for both satellite and terrestrial on-channel repeater service delivery in the 2630-2655 MHz band. This is achieved through the use of CDM based on QPSK modulation with concatenated block and convolutional error correctin
32、g coding. The Digital System E receiver uses state-of-the-art microwave and digital large-scale integrated circuit technology with the primary objective of achieving low-cost production and high-quality performance. ANNEX 2 Digital System A 1 Introduction Digital System A is designed to provide high
33、-quality, multi-service digital radio broadcasting for reception by vehicular, portable and fixed receivers. It is designed to operate at any frequency up to 3 O00 MHz for terrestrial, satellite, hybrid (satellite and terrestrial), and cable broadcast delivery. The System is also designed as a flexi
34、ble, general-purpose integrated services digital broadcasting (ISDB) system which can support a wide range of source and channel coding options, sound-programme associated data and independent data services, in conformity with the flexible and broad-ranging service and system requirements given in R
35、ecommendations ITU-R B0.789 and ITU-R BS.774, supported by Reports ITU-R BS.1203 and ITU-R B0.955. 13 12 Rec. ITU-R B0.1130-4 The system is a rugged, yet highly spectrum and power-efficient, sound and data broadcasting system. It uses advanced digital techniques to remove redundancy and perceptually
36、 irrelevant information from the audio source signal, then it applies closely-controlled redundancy to the transmitted signal for error correction. The transmitted information is then spread in both the frequency and time domains so that a high quality signal is obtained in the receiver, even when w
37、orking in conditions of severe multipath propagation, whether stationary or mobile. Efficient spectrum utilization is achieved by interleaving multiple programme signals and a special feature of frequency reuse permits broadcasting networks to be extended, virtually without limit, using additional t
38、ransmitters all operating on the same radiated frequency. A conceptual diagram of the emission part of the System is shown in Fig. 1. Digital System A has been developed by the Eureka 147 DAB Consortium and is known as the Eureka DAB System. It has been actively supported by the European Broadcastin
39、g Union (EBU) in view of introducing digital sound broadcasting services in Europe in 1995. Since 1988, the System has been successfully demonstrated and extensively tested in Europe, Canada, the United States of America and in other countries worldwide. In this Annex, Digital System A is referred t
40、o as “the System”. The full system specification is available as the European Telecommunications Standard ETS 300401 (see Note 1). NOTE 1 - The addition of a new transmission mode has been found to be desirable, and is being considered as a compatible enhancement to Digital System A to allow the use
41、 of higher power Co-channel terrestrial retransmitters, resulting in larger area gap-filling capabilities, thus providing better flexibility and lower cost in implementing hybrid BSS (sound) for the 1 452-1 492 MHz band. 2 Use of a layered model The System is capable of complying with the Internatio
42、nal Organization for Standardization (ISO) OS1 basic reference model described in IS0 Standard 7498 (1 984). The use of this model is recom- mended in Recommendation IT-R BT. 807 and Report ITU-R BT. 1207, and a suitable interpret- ation for use with layered broadcasting systems is given in the Reco
43、mmendation. In accordance with this guidance, the System will be described in relation to the layers of the model, and the interpretation applied here is illustrated in Table 2. 14 Rec. ITU-R B0.1130-4 FIGURE 1 Conceptual diagram of the transmission part of the System n times rn times Energy dispers
44、al scrambler* Transmitter identification (optional) Sync channel 1 modulator generator 1 Q optional 0 Function applied DAB signal to transmitter 13 * These processors operate independently on each service channel. OFDM: orthogonal frequency division multiplex 1130-01 15 14 Network layer Rec. ITU-R B
45、0.1130-4 TABLE 2 Interpretation of the OS1 layered model Logical channel Name of layer I Description 1 Features specific to the System Data link layer Physical layer _ Application layer Format of the transmitted signal Physical (radio) transmission Presentation layer Practical use of the system Conv
46、ersion for presentation System facilities Audio quality Transmission modes Audio encoding and decoding Audio presentation Service information Session layer I Data selection Transport layer Grouping of data Programme selection Conditional access Programme services Main service multiplex Ancillary dat
47、a Association of data IS0 audio frames Programme associated data Transmission frames Synchronization Energy dispersal Convolutional encoding Time interleaving Frequency interleaving Modulation by 4-DPSK OFDM Radio transmission DPSK: differential PSK Descriptions of many of the techniques involved ar
48、e most easily given in relation to the operation of the equipment at the transmitter, or at the central point of a distribution network in the case of a network of transmitters. The fundamental purpose of the System is to provide sound programmes to the radio listener, so the order of sections in th
49、e following description will start from the application layer (use of the broadcast information), and proceed downwards to the physical layer (the means of radio transmission). 3 Application layer This layer concerns the use of the System at the application level. It considers the facilities and audio quality which the System provides and which broadcasters can offer to their listeners, and the different transmission modes. 16 Rec. ITU-R B0.1130-4 15 3.1 Facilities offered by the System The System provides a signal which carries a multiplex of digital data, and this multi
