1、 STDnBSI ES EN 50255-ENGL 3998 Lb24669 07233b3 879 BRITISH STANDARD Digital audio broadcasting system - Specification of the receiver data interface (RDI) The European Standard EN 50255 1997 has the status of a British Standard ICS 33.160.20 BS EN 50255:1998 nn( n-m U- NO COPYING WITHOUT BSI PERMISS
2、ION EXCEPT AS PERMITTED BY COPYRIGH LAW u - Copyright European Committee for Electrotechnical Standardization Provided by IHS under license with CENELECNot for ResaleNo reproduction or networking permitted without license from IHS-,-STD-BSI BS EN 50255-ENGL 1998 Lb24bb9 0723364 705 Amd. No. BS EN 60
3、266:1998 Date Textaffected National foreword This British Standard is the English language version of EN 50255A997. The UK participation in its preparation was entrusted by Technid Committee EPU100, Audio, video and multimedia systems and equipment, to Subcommiaee EPUl/l, Receiving equipment, which
4、has the responsibility to: This British Standard, having been prepared under the direction of the Electrotechnicai Sector Board, was published under the authority of the Standards Board and comes into effect on 15 June 1998 - aid enquirers to understand the tea - present to the responsible European
5、committee any enquiries on the - monitor related internationai and European developments and promulgate interpretation, or proposals for change, and keep the UK interests informed; them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. C
6、ross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index“, or by using the “Find“ facility of the BSI Standards Electr
7、onic Catalogue. A British Standard does not purport to include aU the necessary provisions of a contract Usem of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This docume
8、nt comprises a front cover, an inside front cover, the EN title page, pages 2 to 13 and back cover. Q BSI 1998 ISBN O 680 29716 2 Copyright European Committee for Electrotechnical Standardization Provided by IHS under license with CENELECNot for ResaleNo reproduction or networking permitted without
9、license from IHS-,-* * u STD-BSI BS EN 50255-ENGL 1998 W 1b24bb9 07233b5 b4L w EUROPEAN STANDARD EN 50255 NOIEME EUROPENNE EUROP error check field is reserved. 100 : CRC was performed, no errors detected, error check field is reserved. O10 : CRC was performed, errors were detected, error check field
10、 contains CRC as received. 110 : CRC check was performed, error check field contains the bitwise sum of received and locally ca- CRC. The other codes are reserved NOTE Although data of one FIB shall be carried in successive RDI frames, padding frames (see 2.1) may be inserted at any position. NOTE I
11、n transmission mode i, the 12 FIBS contained in one transmission frame may be conveyed in a single series of RDI frames. Such series of FIBS are then conveyed once per 96 ms period. Alternatively, the 12 FIBS may be conveyed as four series of three FIBS at 24 ms intervals. NOTE intrammus ion mode W,
12、 the 6 FIBS contained in one transmission frame may be conveyed in a single series of RDI frames. Such series of FIBS are then conveyed once per 48 ms period. Alternatively, the 6 FLBs may be conveyed as two series of three FIBS at 24 ms intervals. 4.6 Lkansmitter identincation information (TII) For
13、 signaing the transmitter idencation information within the RDI, two fonnats are dened in the high capacity mode: a basic one giving an indication on the transmitters bei received and their respective field strengths, and an extended one which in addition provides the complex resuits of the discrete
14、 Fourier transform on the samples of the null symbol of selected pairs of carriers. 4.6.1 Basic format The basic coding for TII can be seen from Figure 8. The following definitions apply: y+ NRT Reserved Field Sub. Id Main Id. O100 strength ISB MSB LSB MSB i Page 9 EN 50256:1997 TII fonnat: This 3 b
15、it field shall specify the format in which “U is provided, as follows: b b10 O10 : Basic format 001 : Extended format The other codes are reserved. NRT (number of received tmnsmimrs): This unsigned binary number, coded in the range 1.24, shall specify the number of transmim for which infomation is p
16、rovided. The other codes are reserved. Main Id., Sub. Id: see i, 8.1.9 Field strength: This 3 bit field shall indicate the relative skngth of the received parn, as follows: o00 : Not signalled O01 : Very weak 010: weak o11 : Quite weak 100 : Medium 101 : Quite strong 110: stz-ong 111 : Very strong b
17、5 b7 Reserved: These bits are reserved. They are set to “O“ for the current definition of the type O001 RDI frame. NOTE TI1 data is not required to be sent as one group of successive RDI frames. It may be sent in several groups of successive RDI frames with others in between. NOTE In each group of T
18、I1 data, starting with a O001 type frame and ending with a O100 type frame, padding frames (see 2.1) may be inserted at any position. 4.6.2 Extended format The extended format for tramnus ionofTiIdatais shown in Figure 9. . NOTE The frame numbering refers to a case where no padding frames are insert
19、ed. Figure 8 - Basic format for TI1 data (TI1 format = 010) O BSI 1998 Copyright European Committee for Electrotechnical Standardization Provided by IHS under license with CENELECNot for ResaleNo reproduction or networking permitted without license from IHS-,-STD.BS1 BS EN 50255-ENGL 1998 m 3b24bb9
20、0723374 b54 m Page 10 EN MnSS:1997 TII format Y Y+l Y+2 NRT Res. 100001 LSB MSB . y + NRT Sub. Id Main Id ISB ISB MSB MSB Sub. Id Main Id ISB ISB MSB MSB O 1234567 O010 O010 Reserved Res. Field Field NSI NCP Field Sub. Id Main Id LSB skength LSB ISB MSB MSB MSB y+NRT +1 y+NRT +2 y+NRT +3 y+NE +4 - R
21、eserved ISignal transmitter 1, carrier pair 1, carrier 1 O Reserved Q-Si transmitter 1, carrier pair 1, carrier 1 O Reserved I-Signa transmitter 1, carrier pair 1, carrier 2 O Reserved Q-Sii transmitter 1, carrier pair 1, carrier 2 O LSB MSB ISB MSB LSB MSB LSB MSB - O . y+K-l y+K y+K+1 y+K+2 Reserv
22、ed ISigna transmitter 1, carrier pair NCP, carrier 2 O010 Reserved Q-Si transmitter 1, carrier pair NCP, carrier 2 O010 Reserved I-Signa tsansmitter 2, carrier pair 1, carrier 1 O010 Reserved Q-Signal transmitter 2, carrier pair 1, carrier 1 O010 ISB MSB ISB MSB ISB MSB LSB MSB y+N-l y+N . Reserved
23、Reserved ISi transmitter 0, carrier pair (NCP), cher 2 ISB MSB Q-Si transmitter (NRT), carrier pair (NCP), carrier 2 LSB MSB NOTE K = NRT + 4*NCP(tmxmitkr 1); N = NRT + L 4*NCP(transmitter k). The frame numbering refers tn a case where no padding frames are inserted. Figure 9 - Extended format for T
24、I1 data (“II format = 001) 0 BSI 1998 Copyright European Committee for Electrotechnical Standardization Provided by IHS under license with CENELECNot for ResaleNo reproduction or networking permitted without license from IHS-,-* m * S FIB1,l FIB 4,3 SubCh X TI1 . S Subch X TI . STD.BS1 BS EN 50255-E
25、NGL 1998 m Lb24669 0723375 590 Page 11 EN 502661997 S SubChX . S . SubCh The following definitions apply Reserved: These bits are reserved. They are set to “O“ for the current definition of the Qpe o001 RDI frame. NRl? See 4.6.1 TII formah See 4.6.1 Main Id, Sub Id: Field strength: See 4.6.1 NCP (nu
26、mber of carrier pairs): This 3 bit field, coded as an unsigned binary number, shall specify the number of carrier pairs for which information is provided for this transmitter. NSI (nd symbo indicator): This flag shall change when data from a new null symbol are transmitted for the nrSt time (toggie
27、fiag). ISi tranmme * r n, der pair m, carrier k, :1997 Y Y+l Y+2 Y+3 6 Specification of the low capacity mode The codmg of the FtDI frames used in the low capacity mode is shown in Figure 11. Reserved: These bits are reserved They are set to “O” for the current defnition of the type 1111 and O111 an
28、d oo00 RDI frames. Data: This 8 bit field shall contain a data byte. The first bit in the of the DAB 3 interface shall be Camed in bit 8. Id f. Ind (identier field indicator): This 2 bit field shall indicate the origin on the data and the contents of the Id. field, as follows: b6 b7 00 : Not signall
29、ed, Id field is reserved. 10 : Main service channel, Id field contains subch.Id O1 : Fast information channel, Id. field is reserved 11 : reserved, Id. field is reserved. Id field: This 6 bit field shall contain an identier to characterize the contents of the data byte, as indicated by the identifie
30、r field indicator. w1, w2, w4, W8 Window signals indicating to which channel the data byte of the same RDI frame belongs (see annex A). Id field Id f. Data w1 w2 w4 W8 1 1 1 1 LSB MSB Ind Reserved NRT o111 Id field Id f. Data w1 w2 w4 W8 1 1 1 1 LSB MSB Ind Reserved Field Sub Id Main Id O010 strengh
31、 LSB MSB LSB MSB LSB MSB NRT See 4.6.1 Field strength: See 4.6.1 Main Id: See 4.6.1 Sub Id: See 4.6.1 NOTE Padding frames may not be included during data -fer. NOTE If the low capacity format is used on an iEC 968 interface (see 3.1), the frames of me 1111 shall be carried in the “Channel A” subfram
32、es and “II, if any, shall be carried in the “Channel B“ subframes. 6 References 1) ETS 300 401. Rculw Broadcast systems; Bgital Auio Broadcasting (DAB) to mobile, portable and fixed rsceivers. European Rlecommunications Standards Institute, Sophia Antipolis, 1995 2) CEVIEC 958:198!3 3) Eureka Projec
33、t 147 Digital Audio Broadcasting. Guidelines for Im-tion and Operation, Volume III. Issue 2.1, Dec. 1994. Y+2 *NR”+ 1) Reserved Field Sub Id Main Id O100 strength LSB MSB LSB MSB . v+n IReserved lo lo lo lo I Figure 11 - Coding of the low capacity mode of the RDI Q BSI 1998 Copyright European Commit
34、tee for Electrotechnical Standardization Provided by IHS under license with CENELECNot for ResaleNo reproduction or networking permitted without license from IHS-,-STD-BSI BS EN 50255-ENGL L998 Lb24669 0723377 3b3 - Page 13 EN 60266:1997 Annex A (informative) Specincation of the DAB 3 interface A.l
35、Introduction The so-called DAB 3 interface is used in the EUREKA 147 and JESSI AE14 digital audio broadcasting (DAB) projects to transfer the data bitstream decoded by the DAB channel decoder to a data sink, such as the WEG audio source decoder. in this report, the DAB 3 interface is described. A.2
36、Description of logical signals The foilowing picture shows the logical signais which comprise the DAB 3 interface. Seriai data is transferred at a tmnsfer rate of 384 kbih, accompanied by a data clock of 384 kHz. Data changes at the falling edge of the data clock, and is stable (i.e. can be clocked
37、in at the receiving end) on the rising data clock edge. The indicated master clock typically has a frequency of either 6.144 MHz (= 16 * 384 kHz), 12.288 MHz (= 32 * 384 kHz) or 24.576 MHz (= 64 * 384 kHz). The kequencies of data clock and master clock must be locked. The phase reiation between mast
38、er clock and data clock is undefined An optiona Viterbi error flag signai indicates detected errors at the input of the DAB channel decoder (the error flag is high for these bits). Thnsferring of valid data occm in bursts of 24 ms on avemge. Validity of the data is indicated by the shown window sign
39、al being high. Data accompanied by window signal beiig low is to be considered invalid data The maximum effective rate of the valid data is 384 kbit/s (in this case, the window s is high continuously). Lower effective data rates are accomplished by signaUing only the appropriate part of the transfer
40、red data bits as valid, i.e. by changing the duty cycle of the window signal. As an option, multiple window signais can be made available to share the serial data between severa applications (for example: WEG audio, FC and data). in that case, these windows should be nonaverlapping, and the windows
41、associated with one application should have an average spacing of 24 ms. A.3 Electrical definition Electrical characteristics of the logical DAB 3 signais are not defined, and may be selected appropriate to the application. The following describes common practice for connections inside modules, and
42、for connections between modules. When used to interconnect ICs, typicaiiy the DAB 3 signals are transferred with OV representing logical “low“ and with the supply voltage (e.g. 5V) representing logical “high“. Levels are commonly according to the ITL definitions. For monitoring cables, BNC connector
43、s are employed. When transferring the signais over a longer distance (e.g. between physically distinct channel decoder and audio decoder hardware modules), symmetrical signals according to the RS-422 electrical characteristics are commonly used in order to minimize interference problems. The signai
44、wires are connected using DB25 connectors. li I: master clock O BSI 1998 Copyright European Committee for Electrotechnical Standardization Provided by IHS under license with CENELECNot for ResaleNo reproduction or networking permitted without license from IHS-,-STD.BS1 BS EN 50255-ENGL Lqq8 m Lb24bb
45、 0723378 2TT m BS EN 50265:1998 BSI 389ChiswickHighRoad London w4 4AL BSI - British Standards Institution BSI is the independent national body responsible for preparing British Standards. It presents the UK view on standards in Europe and at the international level. It is incorpomted by Royal Charte
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