1、$XJXVW(876 implementation guidelines for DVB Terrestrial services;Transmission aspects DIN EN 62553:2013-08 6 62553 IEC:2012(E) TS 101 191, Digital video broadcasting (DVB); DVB mega-frame for Single Frequency Network (SFN) synchronization TR 102 377, Digital Video Broadcasting (DVB); DVB-H Implemen
2、tation Guidelines ARIB STD-B31, Transmission system for digital terrestrial television broadcasting 3 Terms and abbreviations ADC Analog to Digital Converter ARIB Association of Radio Industries and Businesses ASI Asynchronous Serial Interface ATM Asynchronous Transfer Mode BER Bit Error Ratio C/N C
3、arrier to Noise rate CPU Central Processing Unit DTTB Digital Terrestrial Television Broadcasting DVB Digital Video Broadcasting DVB-H DVB Handheld DVB-T DVB Terrestrial D/U Desired to Undesired Signal Ratio END Equivalent Noise Degradation ETSI European Telecommunication Standards Institute FFT Fas
4、t Fourier Transform GPS Global Positioning System IF Intermediate Frequency IFFT Inverse Fast Fourier Transform IIP ISDB-T Information Packet IP Internet Protocol ISDB-T Integrated Services Digital Broadcasting Terrestrial ISI Inter Symbol Interference ISO International Organization for Standardizat
5、ion ITU International Telecommunication Union JEITA Japan Electronics and Information Technology Industries Association MER Modulation Error Ratio MFN Multi-Frequency Network MIP Mega-frame Initialization Packet MMSE Minimum Mean Square Error MPEG Moving Picture Experts Group OFDM Orthogonal Frequen
6、cy Division Multiplex PCR Program Clock Reference PCR_AC PCR Accuracy PCR_FO PCR Offset PCR_OJ PCR Overall Jitter PDH Plesiochronous Digital Hierarchy DIN EN 62553:2013-08 62553 IEC:2012(E) 7 PRBS Pseudo Random Binary Sequence PID Packet Identifier PLL Phased Locked Loop PN Pseudo Random Noise QAM Q
7、uadrature Amplitude Modulation RBW Resolution Bandwidth RF Radio Frequency RS Reed-Solomon SDH Synchronous Digital Hierarchy SFN Single Frequency Network SP Scattered Pilot signal SPI Synchronous Parallel Interface STL Studio to Transmitter Link STS Synchronization Time Stamp TMCC Transmission and M
8、ultiplex Configuration Control signal TS Transport Stream TTL Transmitter to Transmitter Link TV TeleVision UHF Ultra-High Frequency (300 MHz to 3 000 MHz) UI Unit Interval VBW Video Bandwidth VHF Very High Frequency (30 MHz to 300 MHz) VLAN Virtual Local Area Network 4 General conditions of measure
9、ment 4.1 Definitions and classifications of digital terrestrial TV transmission network 4.1.1 General The digital terrestrial broadcasting transmission networks defined in this standard consist of two or more Digital Tv transmitters, relay lines (SDH or PDH contribution link: e.g. satellite, ATM rad
10、io, ATM optical fibre, IP Ethernet VLAN), broadcast-wave relay stations (called Gap-Filler or Transposer) through which the same broadcasting program is transmitted. Figure 1 shows an example of the transmission network. The network is classified in 4.1.2 and 4.1.3 according to the following conditi
11、ons a) Assigned frequencies of each transmitter station which compose the network. b) Signal transmission method between transmitter stations. DIN EN 62553:2013-08 8 62553 IEC:2012(E) %URDGFDVWLQJVWDWLRQ7UDQVPLWWLQJVWDWLRQ 6)1 76UHPXOWLSOHHU76VLJQDOWUDQVPLVVLRQ67/2)0PRGXODWRU77/7UDQVPLWWLQJVWDWLRQ 6
12、)1 5HFHLYHU ARIB STD-B31 Main body 4.3 Test signals and auxiliary signals for measurement 4.3.1 Test signals As test signals for measurement, the following signals can be used. The broadcasting Transport Stream signal used for on-air services, or the equivalent broadcasting Transport Stream signal i
13、n it, or the OFDM signal used for on-air. The specifications of the test signals should be specified for each system, but unless specified, for OFDM signal, the following transmission parameter set should apply, see Tables 2 and 3: Table 2 Parameter set of OFDM signal for test in ISDB-T system Param
14、eter Value Channel bandwidth 6 MHz Number of carriers 8k Guard interval ratio 1/8 Time interleave (see note) I=2 Carrier modulation 64QAM Coding rate of inner code 3/4 or 7/8 NOTE Apply for ISDB-T system. DIN EN 62553:2013-08 10 62553 IEC:2012(E) Table 3 Parameter set of OFDM signal for test in DVB-
15、T/H system Parameter Value Channel bandwidth 6 MHz / 7 MHz / 8 MHz Number of carriers 8k Guard interval ratio 1/8 Time interleave(see note) Native Carrier modulation 64QAM Coding rate of inner code 2/3 NOTE Apply for DVB-T/H system. 4.3.2 Auxiliary signals for measurement 4.3.2.1 General For measure
16、ment of signal delay, the auxiliary signals shown below are used. 4.3.2.2 Reference signal a) 10 MHz signal; 10 MHz reference signal which is synchronized to GPS. b) Sample clock pulse (see note); reference signal which is synchronized to Broadcast TS signal or sample clock signal of OFDM signal. NO
17、TE For 6 MHz ISDB-T system, its frequency is 512/63 MHz. 4.3.2.3 1 pps signal Used for signal delay measurement within 1 s, unless specified, leading edge of 1 pps signal and up edge of 10 MHz sine wave signal should coincide. 1 pps signal and 10 MHz reference signal are obtained by making use of Re
18、ference signal generator with GPS synchronization. 4.3.2.4 Frame sync. Signal Frame sync. Signal is extracted from frame synchronization information multiplexed in broadcast TS signal described in 4.2.1. In case of OFDM signal, frame sync. signal is regenerated from demodulator timing recovery circu
19、it. Frame sync. Signal may be used as a reference signal for signal delay measurement. The relationship between frame sync. Signal and sample clock should be specified for each system. In addition, it is possible to widen the measurement range to more than 1 frame, by making use of the following inf
20、ormation which is multiplexed in Transport stream. x DVB-T system: mega-frame information, refer to ETSI TS 101 191. x ISDB-T system: frame identification signal, refer to ARIB STD-B31. 5 Methods of measurement for signal delay time 5.1 Scope Management of signal delay in transmission network is one
21、 important issue for SFN operation in Digital Terrestrial Broadcasting Network. In this clause, measurement methods for signal delay of transmission lines and equipments, and for relative delay time difference between different DIN EN 62553:2013-08 62553 IEC:2012(E) 11 transmission links are describ
22、ed. Signal delay of video and audio encoder/decoder is out of scope. 5.2 Definition of signal delay time 5.2.1 Delay time As shown in Figure 2 a), delay time should be defined as the delay time between input signal and output signal of same transmission link. Kinds of signal type of input/output are
23、 described in Table 4. 5.2.2 Relative delay time difference As shown in Figure 2 b), relative delay time difference should be defined as the relative time difference between outputs of different transmission links. Kinds of signal type of input/output are described in Table 4. Transmission link Inpu
24、t signal (point #1) Output signal (point #2) Delay time Figure 2 a) Delay time definition IEC 2135/12Figure 2 b) Definition of relative delay time difference Figure 2 Delay time and relative delay time difference definitons Table 4 Combination of signal type Measurement item Measurement point #1 Mea
25、surement point #2 Broadcast TS signal Broadcast TS signal Broadcast TS signal OFDM signal Delay time OFDM signal OFDM signal Broadcast TS signal Broadcast TS signal Relative delay time difference OFDM signal OFDM signal NOTE See details for signal type in Clause 4. 5.3 Direct/indirect measurement 5.
26、3.1 General As defined in 5.2, both signal delay and relative delay time difference are given as the time difference between measurement point #1 and #2. Divide Transmission link #1Transmission link #2Input signal Output signal #1(point #1) Output signal #2(point #2) Relative delay time difference I
27、EC 2136/12DIN EN 62553:2013-08 12 62553 IEC:2012(E) Two measurement systems are considered according to the compared signal. One is direct comparison of signals of #1 and #2; this measurement system is defined as direct measurement system in this standard. On the other hand, the signal timing of poi
28、nts #1 and #2 are measured by making use of common reference signal, this measurement system is defined as indirect measurement system in this standard. Details of these two systems are described below. 5.3.2 Direct measurement system Measurement method in which signals at two measuring points are d
29、irectly compared and measured delay time in this method, input signal is defined as reference signal and output signal is defined as measured signal. Concept of this method is shown in Figure 3a). 5.3.3 Indirect measurementsystem Measurement method in which the common reference signal is used as a r
30、eference of signal delay measurement. As shown in Figure 3b), each measured signal at each measuring point is compared by reference signal and measure the time difference between reference signal and measured signal at each measuring points. The time difference of measurement results is defined as d
31、elay time in this method. TransmissionsystemInput signal Output signalMeasurementsystemReference signalMeasured signalDelay timeMeasurement result = t Delay time = t IEC 2137/12Figure 3a) Direct measurement method TransmissionsystemInput signal Output signalMeasurementsystem #2Reference signalMeasur
32、ed signalDelay timeMeasurementsystem #1Reference signalMeasured signalMeasurementresult = t1Delay time = t2 t1 Measurement result = t2 IEC 2138/12Figure 3b) Indirect measurement method Figure 3 Direct and indirect measurement method 5.4 Measurement place The measurement system is defined regarding m
33、easurement place. DIN EN 62553:2013-08 62553 IEC:2012(E) 13 Places of measurement of points #1 and #2 are in same place, this case is defined as measurement in same place. Measurement of signal delay of transmission equipment is one of these types. On the other hand, places of measurement of points
34、#1 and #2 are in different place, this case is defined as measurement in different places. Measurement of transmission time difference of different station is one of these types. 5.5 Classification of measurement system According to the parameters defined in 5.2 through 5.4, measurement systems are
35、classified into 16 cases shown in Table 5. Examples and measurement systems of each case are described below: a) Case 1: this is a typical case as a measurement of transmission delay of TS transmission line and/or TS transmission equipment in same station. An example of measurement system is shown i
36、n Clause A.1. b) Case 2: signal delay of OFDM modulator is the typical case. The input signal format is TS, and output format is OFDM modulated RF signal. In this case, frame synchronization timing of both signals are compared. An example of measurement system is shown in Clause A.1. c) Case 3: this
37、 is typical case as a measurement of transmission delay of RF transmission line and/or RF transmission equipment in same station. An example of measurement system is shown in Clause A.1. d) Case 4: This is as case 3, but measurement method is different. An example of measurement system is shown in C
38、lause A.2 e) Case 5: this is typical case as a measurement of transmission delay of TS transmission link between different stations. Common frame sync. Signal is used as reference signal. In this case, time difference of reference signal at different positions should be exactly measured before. An e
39、xample of measurement system is shown in Clause A.3. f) Case 6: this is typical case as a measurement of transmission delay of RF transmission link between different stations. Common frame sync. Signal is used as reference signal. In this case, time difference of reference signal at different positi
40、on should be exactly measured before. An example of measurement system is shown in Clause A.3. g) Case 7: this is typical case as a measurement of transmission delay of TS transmission link between different stations. 1 pps signal of GPS is used as reference signal. An example of measurement system
41、is shown in Clause A.3. h) Case 8: this is typical case as a measurement of transmission delay of RF transmission link between different stations. 1 pps signal of GPS is used as reference signal. An example of measurement system is shown in Clause A.4. i) Case 9 case 12: in case that different TS/RF
42、 transmission links are used as redundant, the time difference of different transmission outputs should be measured in the same station. The measurement systems are similar to case 1 case 4, j) Case 13 case 16: these are popular in transmission network composed by different TS/RF transmission links
43、to different stations. These measurement systems are used to verify the time difference of different stations. The measurement systems are similar to case 5 case 8. For cases 13 and 14, time difference of reference signal (frame sync. signal) at different places may be measured by 1 pps signal, or o
44、ther method previously. DIN EN 62553:2013-08 Table 5 Classificationof measurement system for signal delaytime 62553 IEC:2012(E) Signal format Case Definition (note 1) Measurement place(note 2) #1 #2 Direct/indirect (note 3) Reference Signal (note 4)Measuredtiming format (note 5)remarks 1 TS TS 2 TS
45、OFDM 3 OFDM OFDM Frame timing ofmeasured signal See Clause A.1 4 Same place OFDM OFDM direct Input A (note 6) See Clause A.2 5 TS TS 6 OFDM OFDM frame Sync. signal See Clause A.37 TS TS See Clause A.48 DelaytimemeasurementDifferent place OFDM OFDM indirect 1 pps signal Frame timing ofmeasured signal
46、 (note 7) See Clause A.49 TS TS 10 TS OFDM 11 OFDM OFDM Frame timing ofmeasured signal See Clause A.112 Same place OFDM OFDM direct Input A (note 6) See Clause A.213 TS TS 14 OFDM OFDM frame Sync. signal See Clause A.315 TS TS See Clause A.416 Relative delaytimedifference Different place OFDM OFDM i
47、ndirect 1 pps signal Frame timing ofmeasured signal (note 7) See Clause A.4NOTE 1 See 5.2 fordefinition. NOTE 2 See 5.4 formeasurement place. NOTE 3 See 5.3 formeasurement methods. NOTE 4 Referencesignalis defined in 5.3. NOTE 5 Signal formatfor delaytimemeasurement. NOTE 6 In cases 4 and 12, direct
48、 comparisonof 2signals for delaytime measurement. NOTE 7 For accurate measurement,newtechnologyis proposedinClause A.5 ofthis standard. 14 DIN EN 62553:2013-08 62553 IEC:2012(E) 15 6 Methods of measurement for performances of radio wave relay station 6.1 Scope A broadcast wave relay station is impor
49、tant to cover the area where radio wave field strength of main station is not strong enough for receiver. As an example, Gap filler is one of this type of stations. This station type is useful because another frequency resource and/or transmission link is not necessary, and also possible to reduce infrastructure c
