1、STD-CEPT CEPT/ERC/REC LU-OL E-ENGL 1776 i3326434 0034543 521 CEPTERCiREC 1441 E page 1 Distribution: B CEPT/ERC/RECOMMENDATION 14-01 E (Bonn 1995) RADIO-FREQUENCY CHANNEL ARRANGEMENTS FOR HIGH CAPACITY ANALOGUE AND DIGITAL RADIO-RELAY SYSTEMS OPERATING IN THE BAND 5925 MHz - 6425 MHz Recommendation
2、proposed by the Working Group “Spectrum Engineering“ (WGSE) Text of the Recommendation adopted by the “European Radiocommunications Cornmittee“ (ERC): “The European Conference of Postal and Telecommunications Administrations, consichring 1) that it is sometimes desirable to be able to interconnect r
3、adio-relay systems on international Circuits in the 6 GHz band at radio fiequaicies, 2) that, in a frequency band 500 MHz wide, it may be desirable to interconnect up to eight go and eight return channels, 3) that economy may be achieved if at least four go and four return channels can be interconne
4、cted between systems, each of which uses common transmit-receive antennas, 4) that many interfering effects can be substantially reduced by a carefully planned arrangement of the radio frequencies in radio-relay systems employing several radio-frequency channels, 5) that the use of certain types of
5、modulation permits the use of the radio-frequency channel arrangements defined for 1800 telephone channel systems for the transmission of digital channels with a bit rate of the order of 140 Mbitls or synchronous digital hierarchy bit rates, 6) that for these digital radio systems, further economies
6、 are possible by accommodating up to eight go and eight return channels on a single antenna, 7) that it may sometimes be desirable to interleave additional radio-Iequency channels between those of the main pattern, 8) that there may be a desire to interconnect more than eight go and eight return rad
7、io-frequency channels, each with a capacity significantly lower than 1800 telephone channels, 9) that it is also highly desirable to be able to operate systems using a mix of analogue and digital radio channels on the same route, 10) there are techical and economical advantages in adopting harmonise
8、d channel plans, noting a) that this recommendation is based on the ITU-R Recommendation P.383, Edition of August 26,19% STD-CEPT CEPT/ERC/REC 14-01 E-ENGL 1996 H 2326414 0014544 468 m CEPTERUREC 14-01 E Page 2 recommends 1) that the preferred radio-frequency channel arrangement for up to eight go a
9、nd return channels with each channel being either an analogue channel accommodating 1800 telephone channels, or the equivalent, or a digital channel with a capacity of the order of 140 Mbitls, or synchronous digital hierarchy bit rates and operating at frequencies in the lower 6 GHz band (Note i), s
10、houid be as shown at Annex I, 2) that, in a section over which the international connection is arranged, ail the go channels should be in one half of the band, and all the return channels should be in the other half of the band, 3) that the go and return channels on a given section should preferably
11、 use polarisations as shown below: Go Return H(V) 13 5 7 2 4 6 8 V# 2468 1 3 5 7 The following alternative arrangement of polarisation may be used by agreement between the administrations concerned: Go Return H(V) 13 5 7 1 3 5 7 VO 2468 2 4 6 8 4) that, when common transmit-receive antennas for doub
12、le polarisation are used and not more than four channels are accommodated on a single antenna, it is preferred that the channel frequencies be selected by either making n = 1,3,5 and 7 in both halves of the band or making n = 2,4,6 and 8 in both halves of the band (Note 2), 5) that, when additional
13、radio-frequency channels, interleaved between those of the main pattern, are requked, the values of the centre frequenck of these radio-frequency channels should be 14.825 MHz below those of the corresponding main channel fiequencies; in systems for 1800 channels, or the equivalent, and digital high
14、 capacity digital systems, it may not be practical, because of the bandwidth of the moduiated carrier, to use interleaved frequencies, Note 1: Ad bit rates including overhead may be as much as 5% or more higher than net transmission rates. Note 2: When common transmit-receive antennas are used and n
15、ot more than four channels are accommodated on a single antenna, channel frequencies may be selected, by agreement between administrations, by making n = 1,3, 5 and 7 in the lower haif of the band, and n = 2,4,6 and 8 in the upper half of the band. if a second similar antenna is used for four furthe
16、r channels, the channel frequencies may be selected by making n = 2,4,6 and 8 in the lower half of the band and n = 1, 3,5 and 7 in the upper half of the band, but if only three further channels are required, the channel frequencies may be selected by making n = 2,4, and 6 in the lower haif of the b
17、and and n = 3,5 and 7 in the upper half of the band to avoid the difficulty of separating frequencies 8 and 1 . Edition of August 26, 1996 STD-CEPT CEPT/ERC/REC 14-01 E-ENGL 1996 2326434 0014545 3Tit CEPTERUREC 1401 E page 3 6) that up to 16 go and return radio-frequency channels, each with a capaci
18、ty of up to 600 telephone channels, may be obtained on the same route if the additional radio-frequency channels are used simultaneously, with those of the main pattern. Different polarisations should be used alternately for adjacent radio-frequency channels in the same half of the band (Note 3), 7)
19、 that the preferred centre frequency is 6175.0 MHz; other centre frequencies may be used by agreement between the administrations concerned.“ Note 3: “he use of a singie antenna working allows for seven go and seven return channels based cm the preferred arrangement of polarisation and eight go and
20、eight rehun channeis based on the alternative arrangement of polarisation. Edition of August 26,1996 STD-CEPT CEPT/ERC/REC 14-01 E-ENGL 199b 232b414 DULY546 230 9 CEPTIERCIREC 1441 E Annex I, Page 1 xs MHZ 29.65 Annex I n fl f8 fl f8 z1s z2s YS DS 1.3 5945.2 6152.75 6197.24 6404.75 20.2 20.21 44.49
21、252.04 MHzMHzMHzMHzMHzMHzMHzMHz 1. DERIVATION OF RADIO FREQUENCY CHANNELS The radio frequency channel arrangement for carrier spacings of 29.65 h4Hz shall be derived as follows: Let fo be the frequency (MHz) of the centre of the band of frequencies occupied, fn be the centre frequency (MHz) of one r
22、adio-frequency channel in the lower half of the band, h be the centre frequency (MHz) of one radio-frequency channel in the upper half of the band, then the frequencies (MHz) of individual channels are expressed by the following relationships: lower half of the band upper half of the band: fn = fo -
23、 259.45 + 29.65 n h = fo - 7.41 + 29.65 n where n = 1,2, 3,4, 5, 6, 7 or 8 2. CALCULATED PARAMETERS ACCORDING TO ITU-R REC. 746 Z1S: lower guard band Z2S: upper guard band 3. OCCUPIED SPECTRUM: 5925 - 6425 MHz 5.375 MHz - Figure 1 14.84 MHz i-, 5.376 MHz d-+ 6425 MHz 5925 MHz Edition of August 26,1996 2326434 0034099 TbO 9 CElTlERCEtEC 14-01 Radio-frequency channel arrangements for high capacity analogue and digital radio-relay systems operating in the band 5925 MHz - 6425 MHz
