1、 Rec. ITU-R F.240-7 1 RECOMMENDATION ITU-R F.240-7*,*Signal-to-interference protection ratios for various classes of emission in the fixed service below about 30 MHz (Question ITU-R 143/9) (1953-1956-1959-1970-1974-1978-1986-1990-1992-2006) Scope This Recommendation describes minimum signal-to-inter
2、ference protection ratios and frequency separations for various classes of emission in the fixed service below about 30 MHz. The ITU Radiocommunication Assembly, considering a) that knowledge of the signal-to-interference protection ratios for various classes of emission is needed, recommends 1 that
3、 the values of signal-to-interference protection ratios shown in Table 1 for stable conditions, below which harmful interference occurs, should be considered appropriate for the emissions indicated; 2 that studies should be continued to provide values of signal-to-interference protection ratios for
4、stable conditions where they are not shown in Table 1 and also to review the values that are shown; 3 that the studies in connection with Recommendation ITU-R F.339 should be continued for the purpose of determining whether the provisional values given for the fading allowances may be accepted or sh
5、ould be modified; 4 that meanwhile, the values given may be regarded as provisional total fading allowances (combined fading safety factors intensity fluctuation factors) and may be used as a guide, in conjunction with the values for signal-to-interference protection ratios (for stable conditions),
6、appropriate to the various classes of emission; *This Recommendation should be brought to the attention of the Radio Regulations Board and Radiocommunication Study Group 1. *Radiocommunication Study Group 9 made editorial amendments to this Recommendation in 2000 in accordance with Resolution ITU-R
7、44. 2 Rec. ITU-R F.240-7 TABLE 1 Minimum required protection ratios and frequency separations* WANTED SIGNAL CLASS OF EMISSION OF INTERFERING SIGNAL Telegraphy Telegraphy Telegraphy Class of emission A1A Manual A1B 50 Bd (1) A1B 100 Bd A2A Manual A2B 24 Bd F1B 50 Bd 2D = 200 Hz (1) F1B 50 Bd 2D = 28
8、0 Hz (1) 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 dB kHz dB kHz dB kHz dB kHz dB kHz dB kHz dB kHz A1A telegraphy aural reception 13 13 13 13 13 A1B telegraphy 50 Bd printer B = 500 Hz 13 11 0.36 0.44 1.41 (2)12 (2)0.25(2)0.3513 13 0.46 0.54 1.24A1B telegraphy 100 and 120 Bd recorder
9、B = 500 Hz 13 13 13 13 13 A2A telegraphy aural reception A2B telegraphy, 24 Bd F1B telegraphy (3) 50 Bd, printer 2D = 280 Hz: B = 500 Hz 1.0 0.2 0.28 0.6 3 7 7.0 0.32 0.39 0.67F1B telegraphy 50 Bd, printer 2D = 400 Hz: B = 500 Hz 1.0 (2)3 (2)0.35(2)0.507 7 F7B telegraphy 200 Bd, printer ARQ 2D = 400
10、 Hz B = 500 Hz 4 4 4 F7B telegraphy 200 Bd, printer ARQ 2D = 400 Hz: B = 500 Hz 4 4 (4)4 (4)0.40(4)0.55F7B (2), 50 Bd printer Channel 1 8 8 2D = 1 200 Hz B = 1 200 Hz Channel 2 18 18 R3C phototelegraphy 16 16 16 16 16 F3C phototelegraphy 60 rpm, B = 1 000 Hz 15 15 15 1.00 1.20 15 15 just usable 13 1
11、3 13 1 1 21 21 marginally commercial 29 29 29 17 17 33 33 A3E telephony DSB good commercial 56 56 56 44 44 60 60 just usable 7 7 7 5 5 15 15 marginally commercial 23 23 23 11 11 27 27 H3E telephony SSB full carrier(5) good commercial 50 50 50 38 38 54 54 just usable 2 2 2 10 10 10 10 marginally comm
12、ercial 18 18 18 6 6 22 22 R3E telephony SSB reduced carrier(5) good commercial 45 45 45 33 33 49 49 just usable 1 1 1 11 11 9 9 marginally commercial 17 17 17 5 5 21 21 J3E telephony SSB suppressedcarrier(5) good commercial 44 44 44 32 32 48 48 just usable 7 7 7 5 5 15 15 marginally commercial 23 23
13、 23 11 11 27 27 R8E telephonyTwo ISB reduced or suppressed carrier(5) good commercial 50 50 50 38 38 54 54 J7B multichannel V.F. telegraphy 250-3 000 Hz 17.5 17.5 17.5 20.5 20.5 J7B multichannel V.F. telegraphy 300-3 400 Hz (6) 17.5 17.5 1.7 1.7 8.0 17.5 1.7 1.8 9.1 20.5 1.9 1.9 2.0 20.5 R7B multich
14、annel V.F. telegraphy reduced carrier 18.5 18.5 18.5 21.5 21.5 J2D data transmission SSB suppressed carrier PSK/QAM(13) 9 9 9 9 9 9 9 Rec. ITU-R F.240-7 3 TABLE 1 (continued) WANTED SIGNAL CLASS OF EMISSION OF INTERFERING SIGNAL Telegraphy Telegraphy Class of emission F1B 50 Bd 2D = 400 Hz (1) F1B 1
15、00 Bd 2D = 400 Hz F1B 100 Bd 2D = 500 Hz F1B 200 Bd 2D = 500 Hz F7B 100 Bd 2D = 400 Hz F7B 100 Bd 2D = 1500 Hz F7B 200 Bd 2D = 600 Hz 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 dB kHz dB kHz dB kHz dB kHz dB kHz dB kHz dB kHz A1A telegraphy aural reception 13 13 13 13 3 3 3 A1B telegrap
16、hy 50 Bd printer B = 500 Hz 13 13 13 13 (2)3 (2)0.40(2)0.553 3 A1B telegraphy 100 and 120 Bd recorder B = 500 Hz 13 13 13 13 3 3 3 A2A telegraphy aural reception A2B telegraphy. 24 Bd F1B telegraphy (3) 50 Bd, printer 2D = 280 Hz: B = 500 Hz 7 7 7 7 2 2 2 F1B telegraphy 50 Bd, printer 2D = 400 Hz: B
17、 = 500 Hz 7 7 7 7 (2)2 (2)0.45(2)0.602 2 F7B telegraphy 100 Bd, printer ARQ 2D = 400 Hz B = 500 Hz 4 4 4 F7B telegraphy 200 Bd, printer ARQ 2D = 400 Hz: B = 500 Hz (4)4 (4)0.50(4)0.704 4 F7B (3), 50 Bd, printer Channel 1 8 0.85 0.95 1.51 8 8 8 8 8 8 2D = 1 200 Hz B = 1 200 Hz Channel 2 18 0.98 1.1 2
18、.06 18 18 18 18 18 18 R3C phototelegraphy 16 16 16 16 16 16 16 F3C phototelegraphy 60 rpm, B = 1 000 Hz 15 15 15 15 15 1.10 1.20 15 15 just usable 21 21 21 21 17 17 17 marginally commercial 33 33 33 33 35 35 35 A3E telephony DSB good commercial 60 60 60 60 66 66 66 just usable 15 15 15 15 11 11 11 m
19、arginally commercial 27 27 27 27 29 29 29 H3E telephony SSB full carrier(5) good commercial 54 54 54 54 60 60 60 just usable 10 10 10 10 6 6 6 marginally commercial 22 22 22 22 24 24 24 R3E telephony SSB reduced carrier(5) good commercial 49 49 49 49 55 55 55 just usable 9 9 9 9 5 5 5 marginally com
20、mercial 21 21 21 21 23 23 23 J3E telephony SSB suppressedcarrier(5) good commercial 48 48 48 48 54 54 54 just usable 15 15 15 15 11 11 11 marginally commercial 27 27 27 27 29 29 29 R8E telephony Two ISB reduced or suppressed carrier(5) good commercial 54 54 54 54 60 60 60 J7B multichannel V.F. teleg
21、raphy 250-3 000 Hz 20.5 20.5 20.5 20.5 20.5 20.5 20.5 J7B multichannel V.F. telegraphy 300-3 400 Hz (6) 20.5 1.9 1.9 2.1 20.5 1.9 1.9 2.8 20.5 2.0 2.0 2.9 20.5 1.9 2.0 3.1 20.5 20.5 2.4 2.5 3.5 20.5 R7B multichannel V.F. telegraphy reduced carrier 21.5 21.5 21.5 21.5 21.5 21.5 21.5 J2D data transmis
22、sion SSB suppressed carrier PSK/QAM(13) 9 9 9 9 9 9 9 4 Rec. ITU-R F.240-7 TABLE 1 (continued) WANTED SIGNAL CLASS OF EMISSION OF INTERFERING SIGNAL Telegraphy Telegraphy Telephony Class of emission F7B 200 Bd 2D = 3 000 Hz A1B 200 Bd 2D = 1 200 Hz R3C F3C A3E DSB (7) H3E full carrier R3E reduced ca
23、rrier1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 dB kHz dB kHz dB kHz dB kHz dB kHz dB kHz dB kHz A1A telegraphy aural reception 3 3 5 5 10 A1B telegraphy 50 Bd, printer B = 500 Hz 3 3 5 5 10 A1B telegraphy 100 and 120 Bd recorder B = 500 Hz 3 3 5 5 10 A2A telegraphy aural reception 5 11
24、 16 A2B telegraphy, 24 Bd 5 11 16 F1B telegraphy (3) 50 Bd, printer 2D = 280 Hz: B = 500 Hz 2 2 3 3 8 F1B telegraphy 50 Bd, printer 2D = 400 Hz: B = 500 Hz 2 2 3 3 8 F7B telegraphy 100 Bd, printer ARQ 2D = 400 Hz B = 500 Hz 4 4 F7B telegraphy 200 Bd, printer ARQ 2D = 400 Hz: B = 500 Hz 4 4 F7B (3),
25、50 Bd, printer Channel 1 8 8 1.24 1.33 2.32 2D = 1 200 Hz B = 1 200 Hz Channel 2 18 18 1.33 1.51 3.08 R3C phototelegraphy 16 16 F3C phototelegraphy 60 rpm, B = 1 000 Hz 15 15 just usable 17 17 19 20 6 12 17 marginally commercial 35 35 34 35 18 24 29 A3E telephony DSB good commercial 66 66 64 65 39 4
26、5 50 just usable 11 11 13 14 0 6 11 marginally commercial 29 29 28 29 12 18 23 H3E telephony SSB full carrier(5) good commercial 60 60 58 59 33 39 44 just usable 6 6 8 9 5 1 6 marginally commercial 24 24 23 24 7 13 18 R3E telephony SSB reduced carrier(5) good commercial 55 55 53 54 28 34 39 just usa
27、ble 5 5 7 8 6 0 5 marginally commercial 23 23 22 23 6 12 17 J3E telephony SSB suppressed carrier(5) good commercial 54 54 52 53 27 33 38 just usable 11 11 13 14 0 6 11 marginally commercial 29 29 28 29 12 18 23 R8E telephony Two ISB reduced or suppressed carrier(5) good commercial 60 60 58 59 33 39
28、44 J7B multichannel V.F. telegraphy 250-3 000 Hz 20.5 20.5 J7B multichannel V.F. telegraphy 300-3 400 Hz (6) 20.5 3.2 3.3 5.1 20.5 R7B multichannel V.F. telegraphy reduced carrier 21.5 21.5 J2D data transmission SSB suppressed carrier PSK/QAM(13) 9 9 9 9 9 9 9 Rec. ITU-R F.240-7 5 TABLE 1 (continued
29、) WANTED SIGNAL CLASS OF EMISSION OF INTERFERING SIGNAL Telephony Telegraphy Class of emission J3E suppressed carrier B8E reduced or suppressed carrier J2B H2A/H2B 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 dB kHz dB kHz dB kHz dB kHz A1A telegraphy aural reception 11 5 13 7 A1B telegraphy 50 Bd, printer B = 5
30、00 Hz 11 5 13 7 A1B telegraphy 100 and 120 Bd recorder B = 500 Hz 11 5 13 7 A2A telegraphy aural reception 17 11 A2B telegraphy, 24 Bd 17 11 F1B telegraphy (3) 50 Bd, printer 2D = 280 Hz: B = 500 Hz 9 3 3 3 F1B telegraphy 50 Bd, printer 2D = 400 Hz: B = 500 Hz 9 3 3 3 F7B telegraphy 100 Bd, printer
31、ARQ 2D = 400 Hz B = 500 Hz 4 2 F7B telegraphy 200 Bd, printer ARQ 2D = 400 Hz: B = 500 Hz 4 2 Channel 1 F7B (3), 50 Bd, printer 2D = 1 200 Hz B = 1 200 Hz Channel 2 R3C phototelegraphy 16 10 F3C phototelegraphy 60 rpm, B = 1 000 Hz 15 9 just usable 18 12 13 7 marginally commercial 30 24 29 23 A3E te
32、lephony DSB good commercial 51 45 56 50 just usable 12 6 7 1 marginally commercial 24 18 23 17 H3E telephony SSB full carrier(5) good commercial 45 39 50 44 just usable 7 1 2 4 marginally commercial 19 13 18 12 R3E telephony SSB reduced carrier(5) good commercial 40 34 45 39 just usable 6 0 1 5 marg
33、inally commercial 18 12 7 11 J3E telephony SSB suppressed carrier(5) good commercial 39 33 44 38 just usable 12 6 7 1 marginally commercial 24 18 23 17 R8E telephony Two ISB reduced or suppressed carrier(5) good commercial 45 39 50 44 J7B multichannel V.F. telegraphy 250-3 000 Hz 17.5 11.5 J7B multi
34、channel V.F. telegraphy 300-3 400 Hz (6) 17.5 11.5 R7B multichannel V.F. telegraphy reduced carrier 18.5 12.5 J2D data transmission SSB suppressed carrier PSK/QAM(13) 9 9 9 9 6 Rec. ITU-R F.240-7 TABLE 1 (end) WANTED SIGNAL CLASS OF EMISSION OF INTERFERING SIGNAL Multichannel V.F. telegraphy Data tr
35、ansmission Class of emission J7B suppressed carrier 250-3 000 Hz J7B suppressed carrier 300-3 400 Hz R7B reduced carrier J2D PSK/QAM 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 Provisional total fading allowances(8) for the protection of a fading signal against an interfering signal subject to fading and day-to
36、-day intensity fluctuations. (See (9) (dB to be added to values in columns numbered 1) Non-diversity DiversityA1A telegraphy aural reception 11 A1B telegraphy 50 Bd, printer B = 500 Hz 1 27(10)A1B telegraphy 100 and 120 Bd recorder B = 500 Hz 1 A2A telegraphy aural reception 17 A2B telegraphy, 24 Bd
37、 17 F1B telegraphy (3) 50 Bd, printer 2D = 280 Hz: B = 500 Hz 9 F1B telegraphy 50 Bd, printer 2D = 400 Hz: B = 500 Hz 9 27(10)F7B telegraphy 100 Bd, printer ARQ 2D = 400 Hz B = 500 Hz F7B telegraphy 200 Bd, printer ARQ 2D = 400 Hz: B = 500 Hz 12(11)Channel 1 F7B (3), 50 Bd, printer 2D = 1 200 Hz B =
38、 1 200 Hz Channel 2 R3C photelgraphy 20 F3C phototelegraphy 60 rpm, B = 1 000 Hz 20 just usable 20 20 19 18 marginally commercial 34 34 33 30 A3E telephony DSB good commercial 56 56 55 51 17(12)just usable 14 14 13 12 marginally commercial 28 28 27 24 H3E telephony SSB full carrier (5) good commerci
39、al 50 50 49 45 just usable 9 9 8 7 marginally commercial 23 23 22 19 R3E telephony SSB reduced carrier(5) good commercial 45 45 44 40 17(12)just usable 8 8 7 6 marginally commercial 22 22 21 18 J3E telephony SSB suppressed carrier(5) good commercial 44 44 43 39 17(12)just usable 14 14 13 12 marginal
40、ly commercial 28 28 27 24 R8E telephony Two ISB reduced or suppressed carrier(5) good commercial 50 50 49 45 J7B multichannel V.F. telegraphy 250-3 000 Hz J7B multichannel V.F. telegraphy 300-3 400 Hz (6) R7B multichannel V.F. telegraphy reduced carrier J2D data transmission single sideband suppress
41、ed carrier PSK/QAM(13) 9 9 9 9 Rec. ITU-R F.240-7 7 Notes to Table 1: DSB: Double sideband ISB: Independent sideband SSB: Single sideband * Under “class of emission”, B represents the receiver bandwidth and 2D represents the total frequency shift. (1) Bandwidth of interfering signals limited to 500
42、Hz. (2) For a probability of character error Pc= 0.0001. (3) For a probability of character error Pc= 0.001. (4) For a traffic efficiency of 90%. (5) For telephony the values of protection ratios for stable conditions have been derived from information contained in Annexes 1 and 2. The figures for A
43、3E telephony are valid only for reception with an SSB receiver. (6) Values derived from information contained in Annex 3. (7) Average degree of modulation 70%; sideband components extended to 3 kHz. (8) Combined allowances for fading safety factor and intensity fluctuation factor. (9) The probabilit
44、y distribution of the radio of two signals fading independently has been applied. The combined intensity fluctuation allowance for two signals has been taken as 7 dB, which represents a compromise between the 0 dB allowance, appropriate to perfectly correlated intensity fluctuations of the two signa
45、ls, and the 14 dB allowance appropriate to uncorrelated intensity fluctuations of the two signals. (10) For protection 99.99% of the time. (11) Based on 90% traffic efficiency. (12) Based on 90% protection. (13) The protection ratio for the J2D wanted signal is the values for user data rate of 3.2 k
46、bit/s in the wanted signal. For the other user data rate, add the correction factor (dB) shown below: User data rate (kbit/s) 3.2 or less 4.8 6.4 8.0 9.6 12.8 Correction factor (dB) 0 4 7 10 12 18 5 that Annex 1 should be referred to for measurement of protection ratios for J3E emission; 6 that Annex 2 should be referred to for conversion factors for deriving the protection ratios; 7 that Annex 3 should be referred to for measurement of protection ratios and minimum necessary frequency separation for class of emission J7B. 8 Rec. ITU-R F.240-7 8 that the Notes shown bel
