1、Rec. ITU-R F.748-4 1 RECOMMENDATION ITU-R F.748-4 Radio-frequency arrangements for systems of the fmed service operating in the 25,26 and 28 GHz bands (Questions TTU-R 10819 and ITU-R 229/9) (1992-1994-1995-1999-2001) The ITU Radiocommunication Assembly, considering that the bands 24.25-25.25 GHz, 2
2、5.25-27.5 GHz and 27.5-29.5 GHz are allocated to fixed a) and other services; b) that some administrations use digital systems for point-to-point (P-P) and/or point- to-multipoint (P-MP) applications; c) that the bands are used for differing applications by various administrations and that these app
3、lications require different frequency plans; d) that the bands may also be used for fixed wireless access (FWA) systems; e) that several types of service with various capacities may be in simultaneous use in these frequency bands; 0 that the band allocated to each service or even to each administrat
4、ion may vary from one country to another; g) that the applications in these frequency bands may require differing channel bandwidths; h) that a high degree of compatibility between different systems and between radio-fie- quency (RF) channels of different arrangements can be achieved by selecting al
5、l channel centre frequencies from a homogeneous basic pattern; j) that allocation of frequency blocks to FWA systems allows flexible deployment of various technologies including provision for inter-systemservices operation and overall spectrum efficiency, recom m ends 1 27.5-29.5 GHz bands should be
6、 based on homogeneous patterns; 2 that the preferred RF channel arrangement for the 24.25-25.25 GHz, 25.25-27.5 GHz and that the homogeneous pattern with a preferred 3.5 MHz interval be defined by the relation: fp =fr i- 3.5 P where: 1 I p I 285 for the band 24.25-25.25 GHz 287 I p I 928 for the ban
7、d 25.25-27.5 GHz 930 I p I 1500 for the band 27.5-29.5 GHz fr : reference frequency of the homogeneous pattern; 75 2 Rec. ITU-R F.74-4 3 that the homogeneous pattern with a preferred 2.5 MHz interval be defined by the relation: fp =fr+ 2 + 2.5 where: 1 I p I 399 for the band 24.25-25.25 GHz 401 I p
8、I 1299 for the band 25.25-27.5 GHz 1301 I p I 2099 for the band 27.5-29.5 GHz fr : reference frequency of the homogeneous pattern; 4 should be: that the reference frequency of the homogeneous pattern for international connections fr = 24248 MHz 5 in the other; that all go channels should be in one h
9、alf of any bidirectional band, and all return channels 6 that the channel spacings, XS, centre gap, YS, and the lower and upper band limits, ZlS, Z2S, should be agreed by the administrations concerned, dependent on the application and the channel capacity envisaged (see Recommendation ITU-R F.746 fo
10、r definitions of XS, YS and 2s); 7 with the homogeneous pattern. NOTE 1 - Due regard has to be taken that, in certain countries, a 3.5 MHz homogeneous pattem, interleaved by 1.75 MHz from that referred in recommends 2, is used in conjunction with the main pattem. NOTE 2 - Examples of channel arrange
11、ments based on this Recommendation are described in Annexes 1 and 2. that allocated blocks should result fiom aggregation of contiguous channels in accordance NOTE 3 - Examples of FWA system block (sub-band) arrangements are described in Annex 3. ANNEX 1 Radio-frequency channel arrangements for some
12、 CEPT administrations in the band 24.5-26.5 GHz in accordance with recommends 2 An example of the RF channel arrangement based on this Recommendation for carrier spacings of 112 MHz, 56 MHz, 28 MHz, 14 MHz, 7 MHz and 3.5 MHz is derived as follows (see Fig. 1): Let fo be the reference frequency of 25
13、 501 MHz = fr + (358 x 3.5) MHz, fn be the centre frequency of a RF channel in the lower half of the band, f; be the centre frequency of a RF channel in the upper half of the band, . 76 Rec. ITU-R F.748-4 3 then the centre frequencies of individual channels are expressed by the following relationshi
14、ps: a) for systems with a carrier spacing of 112 MHz: lower half ofband: fn = fo - 1008 + 112 n upper half of band: fi = fo + 1 12 n MHz MHz where: n = 1,2,3, . . . 8 for systems with a carrier spacing of 56 MHz: lower half ofband: fn = fo - 980 + 56 n b) MHz MHZ upper half of band: fi = fo + 28 + 5
15、6 n where: n = 1,2,3,. . . 16 cl for systems with a carrier spacing of 28 MHz: lower half ofband: fn = fo - 966 + 28 n upper half of band: f, = fi + 42 + 28 n MHz MHz where: n = 1,2,3,. . .32 for systems with a carrier spacing of 14 MHz: lower half of band: d) fn = fo - 959 + 14 n upper half of band
16、: fi = fo + 49 + 14 n MHZ MHZ where: n = 1,2,3,. . .64 (SeeNote 1) e) for systems with a carrier spacing of 7 MHz: lower half of band: fn = fo - 955.5 + 7 n MHz MHZ upper half of band: fi = fo + 52.5 + 7 n where: n = 1,2,3,. . . 128 for systems with a carrier spacing of 3.5 MHz: lower half ofband: f
17、n = fo - 953.75 + 3.5 n upper half ofband: fi = fo + 54.25 + 3.5 n f) MHz MHz where: n=l,2,3 ,. 256. 77 4 a) Rec. ITU-R F.748-4 8x 112MHZ +I 8x 112MHz FiGURE 1 b) 16x56MHz 16x56MHz c) 32x28MHz 32 x28 MHZ d) 64xl4MHz 64xl4MHz -I 128x7MHz 128 x 7 MHz 24.5 GHz I) 25.445 GHz 256 x 3.5 MHz 256 x 3.5 MHz
18、25.557 GHz 26.5 GHz 074841 NOTE 1 - The RF channel arrangements of a) to e) of this Annex use channel centre frequenciesf, and fi selected from the homogeneous pattern of recommends 2. The arrangement of 8 f) above uses frequencies spaced by 3.5 MHz but interleaved between the homogeneous pattern of
19、 recommends 2 with an offset of 1.75 MHz. NOTE 2 - Figure 1 gives occupied spectrum in the 24.5-26.5 GHz band. The centre and edge guardbands may be reduced, by agreement between administrations, to allow the use of an increased number of lower capacity systems, by the addition of extra channels usi
20、ng frequencies derived from the homogeneous pattern of recommends 2. NOTE 3 - The RF channel arrangements of fj a) to f) of this Annex may be used in digital systems for P-P and/or P-MP applications. 78 Rec. ITU-R F.748-4 5 ANNEX 2 RF channel arrangements for some CEPT administrations in the band 27
21、.5-29.5 GHz in accordance with recommends 2 An example of the RF channel arrangement based on this Recommendation for camer spacings of 112 MHz, 56 MHz, 28 MHz, 14 MHz, 7 MHz and 3.5 MHz is derived as follows: Let fo be the centre frequency of 28 500.5 MHz = fr + (1 215 x 3.5) MHz, fn be the centre
22、frequency of a RF channel in the lower half of the band, f; be the centre frequency of a RF channel in the upper half of the band, then the centre frequencies of individual channels are expressed by the following relationships: a) for systems with a carrier spacing of 1 12 MHz: lower half of band: f
23、n = fi - 1 008 + 1 12 n upper half of band: fi = fi + 112 n where: n = 1,2, 3, . . . 8 for systems with a carrier spacing of 56 MHz: lower half ofband: fn = fo - 980 + 56 n upper half of band: fi = fi + 28 + 56 n b) where: n = 1,2,3,. . . 16 for systems with a carrier spacing of 28 MHz: lower half o
24、f band: fn = fo - 966 + 28 n upper half of band: fi = fo + 42 + 28 n c) where: n = 1,2,3,. . .32 for systems with a carrier spacing of 14 MHz: lower half of band: fn = fo - 959 + 14 n upper half of band: fi = fi + 49 + 14 n d) where: n = 1,2,3,. . .64 for systems with a carrier spacing of 7 MHz: low
25、er half of band: fn = fo - 955.5 + 7 n upper half of band: fi = fo + 52.5 + 7 n e where: n = 1,2,3,. . . 128 (SeeNote 1) MHZ MHZ MHz MHz MHZ MHZ MHZ MHz MHZ MHZ 79 6 Rec. ITU-R F.748-4 4 f) for systems with a carrier spacing of 3.5 MHz: lower halfofband: fn = fo - 953.75 + 3.5 n upper half ofband: f
26、i = fo + 54.25 + 3.5 n MHz MHz 8x112MHz z6 8x112MHz where: n = 1,2,3, . . . 256. b) 16x56MHz FIGURE 2 16x56MHz d) 64x I4MHz 64x14MHz 4 256 x 3.5 MHz 256 x 3.5 MHz 27.5 GHz 28.4445 GHz 28.5565 GHz 29.5 GHz 074842 NOTE 1 - The RF channel arrangements of 4 a) to e) of this Annex use channel centre freq
27、uenciesf, and selected from the homogeneous pattern of recommends 2. The arrangement of $ f) above uses frequencies spaced by 3.5 MHz but interleaved between the homogeneous pattern of recommends 2 with an offset of 1.75 MHz. NOTE 2 -Figure 2 gives occupied spectrum in the 27.5-29.5 GHz band. The ce
28、ntre and edge guardbands may be reduced, by agreement between administrations, to allow the use of an increased number of lower capacity systems, by the addition of extra channels using frequencies derived from the homogeneous pattern of recommends 2. NOTE 3 - The RF channel arrangements of Q a) to
29、I) of this Annex may be used in digital systems for P-P andor P-MP applications. , 80 Rec. ITU-R F.748-4 Paired block 7 Lower frequency block Upper frequency block (MW (MHz) ANNEX 3 NA BEI RF block arrangements in the bands 24.25-25.25 GHz and 25.27-26.98 GHz in accordance with recommends 7 24 250-2
30、4 290 24 290-24 330 25 050-25 090 25 090-25 130 1 The following arrangements can be referred to for use by administrations wishing to implement arrangements based on frequency blocks. Arrangement based on a 40 MHz frequency block C/C D/D 1.1 RF block arrangement description 24 330-24 370 24 370-24 4
31、1 O 25 130-25 170 25 170-25 210 :The band 24.25-25.25 GHz is divided into five paired frequency blocks (40 MHz + 40 MHz) as follows: E/E 24410-24450 -25 210-25 250 1.2 Usage - - The block arrangement is for both P-P and P-MP systems. Frequency blocks are paired to facilitate frequency division duple
32、x (FDD) systems. Preference is given to the lower frequency blocks for downlink operation and to the upper frequency blocks for uplink operation. Time division duplex (TDD) systems may operate in either the lower or upper frequency blocks. - - Operators may subdivide the 40 MHz blocks according to t
33、heir needs. Larger frequency blocks can be made available through the aggregation of 40 MHz paired blocks. 2 Arrangement based on a 60 MHz frequency block 2.1 RF block arrangement description The band 25.27-26.98 GHz is divided into 13 paired frequency blocks (60 MHz + 60 MHz) as follows. 81 8 Paire
34、d block Lower frequency block (MW Rec. ITU-R F.748-4 Upper frequency block (MW DID1 D2/D2 25 270-25 330 25 330-25 390 26 125-26 185 26 185-26 245 D3D3 26 245-26 305 25 390-25 450 Bl/B1 B2/B2 25 450-25 5 10 25 5 10-25 570 26 305-26 365 26 365-26 425 B3B3 B4/B4 25 570-25 630 26425-26 485 25 630-25 690
35、 26485-26 545 B5/B15 B6/B6 2.2 Usage - - The block arrangement is for both P-P and P-MP systems. Frequency blocks are paired to facilitate FDD systems. Preference is given to the lower frequency blocks for uplink operation and to the upper frequency blocks for downlink operation. TDD systems may ope
36、rate in either the lower or upper frequency blocks. Operators may subdivide the 60 MHz blocks according to their needs. Larger frequency blocks can be made available through the aggregation of 60 MHz paired blocks. - - 25 690-25 750 25 750-25 8 1 O 26 545-26 605 26 605-26 665 . I B7/B7 82 I 25 8 10-25 870 I 26665-26 725 D4/D4 D5D5 25 945-26 005 26 005-26 065 26 800-26 860 26 860-26 920 D6D6 26 065-26 125 26 920-26 980
