1、 Rep. ITU-R M.2111 1 REPORT ITU-R M.2111 Sharing studies between IMT-Advanced and the radiolocation service in the 3 400-3 700 MHz bands (2007) 1 Introduction The Radiocommunication Assembly 2003 adopted Recommendation ITU-R M.1645 on the Framework and overall objectives for the future development o
2、f IMT-2000 and IMT-Advanced systems. WRC-07 Agenda item 1.4 has “to consider frequency-related matters for the future development of IMT-2000 and systems beyond IMT-2000 taking into account of the results of ITU-R studies in accordance with Resolution 228 (Rev.WRC-03)”. Report ITU-R M.2078 provides
3、the estimated spectrum bandwidth requirement for pre-IMT-2000, IMT-2000 and IMT-Advanced for the year 2020, and it was calculated for both low and high user demand scenarios to be 1 280 MHz and 1 720 MHz respectively. The frequency band 3 400-4 200 MHz has been identified as a candidate band for IMT
4、-Advanced systems, as indicated by Report ITU-R M.2079. The allocations for this band are provided in Article 5 of the Radio Regulations (RR). Several administrations have deployed mobile radar systems that operate in the 3 400-3 700 MHz frequency band. These systems have been operating in this band
5、 for over thirty years. These radar systems are expected to continue to operate within these allocations for many more years. This Report provides sharing studies between radar systems and IMT-Advanced systems in the bands 3 400-3 700 MHz, and potential interference mitigation techniques. Sharing st
6、udies are shown in Annexes 1 and 2, and potential interference mitigation techniques which may be applied to both IMT-Advanced systems and radar systems are shown in Annex 3. This Report contains multiple studies using different scenarios and assumptions, and consequently has different results. Desp
7、ite these differences of assumptions, some similar results have been achieved. 2 Scope of the Report This Report only deals with the sharing between IMT-Advanced and the radiolocation service in the bands 3 400-3 700 MHz, including potential interference mitigation techniques which may be applicable
8、 for IMT-Advanced and the radiolocation systems. The sharing between the fixed-satellite service and IMT-Advanced is addressed in a separate Report. The allocated services in the bands 3 400-3 700 MHz specified in RR Article 5 are listed in the following table. 2 Rep. ITU-R M.2111 3 400-3 700 MHz Al
9、location to services Region 1 Region 2 Region 3 3 400-3 600 FIXED FIXED-SATELLITE (space-to-Earth) Mobile Radiolocation 5.431 3 600-3 700 FIXED FIXED-SATELLITE (space-to-Earth) Mobile 3 400-3 500 FIXED FIXED-SATELLITE (space-to-Earth) Amateur Mobile Radiolocation 5.433 5.282 5.432 3 500-3 700 FIXED
10、FIXED-SATELLITE (space-to-Earth) MOBILE except aeronautical mobile Radiolocation 5.433 5.435 5.282 In the bands 435-438 MHz, 1 260-1 270 MHz, 2 400-2 450 MHz, 3 400-3 410 MHz (in Regions 2 and 3 only) and 5 650-5 670 MHz, the amateur-satellite service may operate subject to not causing harmful inter
11、ference to other services operating in accordance with the Table (see No. 5.43). Administrations authorizing such use shall ensure that any harmful interference caused by emissions from a station in the amateur-satellite service is immediately eliminated in accordance with the provisions of No. 25.1
12、1. The use of the bands 1 260-1 270 MHz and 5 650-5 670 MHz by the amateur-satellite service is limited to the Earth-to-space direction. 5.431 Additional allocation: in Germany, Israel and the United Kingdom, the band 3 400-3 475 MHz is also allocated to the amateur service on a secondary basis. (WR
13、C-03) 5.432 Different category of service: in Korea (Rep. of), Japan and Pakistan, the allocation of the band 3 400-3 500 MHz to the mobile, except aeronautical mobile, service is on a primary basis (see No. 5.33). (WRC-2000) 5.433 In Regions 2 and 3, in the band 3 400-3 600 MHz the radiolocation se
14、rvice is allocated on a primary basis. However, all administrations operating radiolocation systems in this band are urged to cease operations by 1985. Thereafter, administrations shall take all practicable steps to protect the fixed-satellite service and coordination requirements shall not be impos
15、ed on the fixed-satellite service. 5.435 In Japan, in the band 3 620-3 700 MHz, the radiolocation service is excluded. 3 Sharing studies The detailed results of the sharing studies are included in Annexes 1 to 3. Specifically, Annex 1 presents sharing studies of the required separation distance betw
16、een the radiolocation service and IMT-Advanced; Annex 2 discusses required frequency separation; and Annex 3 addresses potential interference mitigation techniques. In each annex, two sets of sharing studies are presented that are based on different scenarios and assumptions. Fundamental differences
17、 in the sharing studies are summarized in Table 1. Extensive comparisons of each study are included in each Annex. The key results of these sharing studies are shown in Table 2. Rep. ITU-R M.2111 3 TABLE 1 Highlights of each sharing study in Annexes 1 and 2 Topic Annex 1 Annex 2 Study A Study B Stud
18、y A Study B Focus of study Range separation in both co-channel case and adjacent channel case Range separation in combination of co-channel case and adjacent channel case Frequency separation in adjacent channel case Frequency separation in combination of co-channel case and adjacent channel case In
19、terference conditions Aggregated IMT-Advanced interference to a radar Aggregated IMT-Advanced interference to a radar Point-to-point between one IMT-Advanced element and radar at distances of 1, 5, 20 and 40 km One IMT-Advanced unit as interference to a radar Propagation model (airborne radar case)
20、Free-space propagation loss with additional random and uniformly distributed building/terrain obstruction loss between 0 and 20 dB Recommendation ITU-R P.452 was used to compute propagation loss with a time percent of 20%. Building penetration was also taken into account as an additional random vari
21、able in the range 0 to 20 dB Free-space or diffraction propagation loss without additional building/terrain obstruction loss Recommendation ITU-R P.452 was used to compute propagation loss with a time percent of 0.001%. Building penetration was also taken into account as an additional random variabl
22、e in the range 0 to 20 dB Propagation model (shipborne radar case) Similar propagation model described in Recommendation ITU-R M.1652 Recommendation ITU-R P.452 was used to compute propagation loss with a time percent of 20%. Building penetration was also taken into account as an additional random v
23、ariable in the range 0 to 20 dB Free-space or diffraction propagation loss without additional building/terrain obstruction loss Recommendation ITU-R P.452 was used to compute propagation loss with a time percent of 0.001%. Building penetration was also taken into account as an additional random vari
24、able in the range 0 to 20 dB Recommendation titles: Recommendation ITU-R M.1652 Dynamic frequency selection (DFS) in wireless access systems including radio local area networks for the purposes of protecting the radiodetermination services in the 5 GHz band. Recommendation ITU-R P.452 Prediction pro
25、cedure for the evaluation of microwave interference between stations on the surface of the Earth at frequencies above about 0.7 GHz. It was noted by the ITU-R that when used with representative terrain profiles, Recommendation ITU-R P.452 is the most appropriate prediction method for each individual
26、 interfering path and ITU-R M.1652 is not suitable for sharing studies in cases where interference is limited to less than 50% time or for paths longer than about 50 km. 4 Rep. ITU-R M.2111 TABLE 2 Key results of each sharing study in Annexes 1 and 2 Results Study A Study B Range separation IMT to r
27、adar Shipborne Radar A-64 km (1.1 km in adjacent channel case) Radar B-57 km Radar A-77 km Radar B-60 km Land-based Radar B-35 km (3.3 km in adjacent channel case) Not calculated Airborne 365 km (0 km in adjacent channel case) 360 km Range separation radar to IMT Shipborne Radar A-164 km Radar B-258
28、 km Not calculated Airborne 715 km Not calculated Frequency separation IMT to radar Shipborne 100 MHz case: Radar A- from 57 MHz (at 40 km) to 123 MHz (at 1 km) Radar B- from 56 MHz (at 40 km) to 128 MHz (at 1 km) 25 MHz case: Radar A- from 21 MHz (at 40 km) to 42 MHz (at 1 km) Radar B- from 19 MHz
29、(at 40 km) to 59 MHz (at 1 km) 100 MHz case: Radar A-89 MHz (at 40 km) Radar B-136 MHz (at 40 km) 25 MHz case: Radar A-36 MHz (at 40 km) Radar B-40 MHz (at 40 km) Airborne 100 MHz case: From 51 MHz (at 8.1 km) to 63 MHz (at 9.4 km) 25 MHz case: From 13 MHz (at 8.1 km) to 21 MHz (at 9.4 km) 100 MHz c
30、ase: 58 MHz (at 40 km) 25 MHz case: 39 MHz (at 40 km) Rep. ITU-R M.2111 5 TABLE 2 (end) Results Study A Study B Frequency separation radar to IMT Shipborne 100 MHz case: Radar A-1GHz (at 40 km) Radar B-from 187 MHz (at 40 km) to 3 900 MHz (at 1 km) 25 MHz case: Radar A-148 MHz (at 40 km Radar B- fro
31、m 218 MHz (at 40 km) to 3 900 MHz (at 1 km) Not calculated Airborne 100 MHz case: From 123 MHz (at 8.1 km) to 750 MHz (at 9.4 km) 25 MHz case: From 148 MHz (at 8.1 km) to 784 MHz (at 9.4 km) Not calculated NOTE 1 25 MHz case refers to an IMT signal bandwidth of 25 MHz. Likewise, 100 MHz case refers
32、to an IMT signal bandwidth of 100 MHz. 4 Potential interference mitigation techniques Potential interference mitigation techniques which may, if appropriate, be applied to IMT-Advanced systems and radar systems are investigated in this Report. Initial descriptions of potential mitigation techniques
33、are included in Annex 3 Study A. It should be noted that some of the techniques applied to IMT-Advanced systems are implemented in order to reduce the self-interference in their own IMT-network, which will contribute to reduce the interference to radars. 5 Conclusions The studies show that co-freque
34、ncy sharing between radiolocation services and IMT devices is not feasible in the same geographic area, without the application of mitigation techniques. Separation distances and frequency separation summarized in Table 2 are required to protect victim systems. See studies in Annexes 1 and 2 for det
35、ails. The results in this report are based on interference power (I/N = 6 dB) evaluations. The range separation calculation results are similar. Sharing studies between airborne radar and IMT-Advanced have concluded that: The required separation distance is approximately 360 km in co-channel case. U
36、sing non-overlapping adjacent channel analysis, the required separation distance is approximately 0 km, depending on the radar type and antenna type. 6 Rep. ITU-R M.2111 Sharing studies between land-based/shipborne radar and IMT-Advanced have concluded that: The required separation distance is appro
37、ximately 70 km in co-channel case. Using non-overlapping adjacent channel analysis, the required separation distance is less than 1 km, depending on the radar type and antenna type. The frequency separation analyses concluded that: The frequency separations vary between 13 and 136 MHz when interfere
38、nce is from IMT-Advanced to radar. Based on a worst-case analysis, the frequency separation is greater than 1GHz when interference is from radar to IMT-Advanced. Potential mitigation techniques shown in Annex 3 may reduce the interference, and may facilitate sharing between IMT-Advanced systems and
39、radiolocation systems. For example, a calculation of a hypothetical scenario from radar to IMT-Advanced case resulted in an 80% reduction in frequency separation to approximately 560 MHz, and another calculation resulted in a 60% reduction in range separation to approximately 70 km, if such mitigati
40、on techniques could be applied. Further studies are required to develop the actual specifications of mitigation techniques, such as procedures and performance in DFS functionality. Administrations may consider geographical segregation and mitigation techniques to facilitate sharing between IMT-Advan
41、ced and radar systems. Sharing studies between Land-based/Shipborne Radar and IMT-Advanced have concluded that: The required separation distance is approximately 70 km in co-channel case. Using non-overlapping adjacent channel analysis, the required separation distance is less than 1 km, depending o
42、n the radar type and antenna type. The frequency separation analyses concluded that: The frequency separations vary between 13 and 136 MHz when interference is from IMT-Advanced to radar. Based on a worst case analyses frequency separation is greater than 1 GHz when interference is from radar to IMT
43、-Advanced. These results show that co-frequency sharing between radiolocation services and IMT devices could be difficult in the same geographical area within the application of mitigation techniques. Potential mitigation techniques shown in Annex 3 may reduce the interference, and may facilitate sh
44、aring between IMT-Advanced systems and radiolocation systems. For example, a calculation of a hypothetical scenario from radar to IMT-Advanced case resulted in an 80% reduction in frequency separation to approximately 560 MHz, and another calculation resulted in a 60% reduction in range separation t
45、o approximately 70 km, if such mitigation techniques could be applied. Further studies are required on the development of the actual specifications of mitigation techniques, such as procedures and performance in functionality. Administrations may consider geographical segregation and mitigation tech
46、niques to facilitate sharing between IMT-Advanced and radar systems. 6 Definitions and abbreviations 6.1 Definitions No new definitions were included. Rep. ITU-R M.2111 7 6.2 Abbreviations ACLR Adjacent channel leakage power ratio CDF Cumulative distribution function CDMA Code division multiple acce
47、ss DFS Dynamic frequency selection FDR Frequency dependent rejection FDRBBFrequency dependent rejection baseband IPS Integrated propagation system (computer model) LOS Line of sight NLOS Non line of sight NTIA National Telecommunications and Information Administration OFDM Orthogonal frequency divis
48、ion multiplexing OFR Off frequency rejection OTR On tune rejection OOB Out of band SDMA Spatial division multiple access Annex 1 Compatibility between the radiolocation service and IMT-Advanced systems operating in the mobile service in the 3 400-3 700 MHz band Study A 1 Introduction This annex prov
49、ides a sharing study addressing aggregate interference and adjacent channel interference. The result of the sharing study shows that co-channel interference is very severe and introduction of various mitigation techniques as well as geographical segregation could be considered. It also shows that adjacent channel interference from IMT-Advanced to the radar systems would be within the tolerable level if radar is not located within a service cell of IMT-Advanced systems. Separation distances obtained in the simulation is necessary in principle. However, taking into a
