1、 Rec. ITU-R RS.1632 1 RECOMMENDATION ITU-R RS.1632*Sharing in the band 5 250-5 350 MHz between the Earth exploration-satellite service (active) and wireless access systems (including radio local area networks) in the mobile service (Question ITU-R 218/7) (2003) The ITU Radiocommunication Assembly, c
2、onsidering a) that the frequency band 5 250-5 350 MHz is allocated to the Earth exploration-satellite service (EESS) (active) and to the radiolocation service on a primary basis; b) that some administrations have proposed to use the band 5 250-5 350 MHz for low power high speed wireless local area n
3、etworks (WLANs), or radio local area networks (RLANs); c) that these high speed WLANs are proposed to be deployed in the band as unlicensed devices, making regulatory control of their deployment density non-feasible, recognizing a) that studies are continuing in ITU-R with a view to facilitating sha
4、ring of wireless access systems (including RLANs) with EESS (active), noting a) that some administrations have adopted technical limits which permit wireless access systems (including RLANs) to operate with an e.i.r.p. power limit of l W, while other administrations have adopted more stringent e.i.r
5、.p. limits, recommends 1 that sharing between spaceborne active sensors of the EESS with the characteristics as given in Annex 1 and high speed WLANs in the 5 250-5 350 MHz band is feasible with wireless access systems (including RLANs) having constraints such as those given in Annex 2; 2 that the l
6、evel of protection required for EESS systems as given in Annex 1 may also be achieved using alternative sets of operational and technical limits being studies under recognizing a). *Radiocommunication Study Group 7 made editorial amendments to this Recommendation. 2 Rec. ITU-R RS.1632 Annex 1 Techni
7、cal characteristics of spaceborne active sensors in the 5 250-5 570 MHz band Technical characteristics of spaceborne active sensors in the 5.3 GHz frequency range are given in Tables 1 and 2. TABLE 1 5.3 GHz typical spaceborne imaging radar characteristics Value Parameter SAR1 SAR2 SAR3 SAR4 Orbital
8、 altitude (km) 426 (circular) 600 (circular) 400 (circular) 400 (circular) Orbital inclination (degrees) 57 57 57 57 RF centre frequency (MHz) 5 305 5 405 5 405 5 300 Peak radiated power (W) 4.8 4 800 1 700 1 700 Polarization Horizontal (HH) Horizontal and vertical (HH, HV, VH, VV) Horizontal and ve
9、rtical (HH, HV, VH, VV) Horizontal and vertical (HH, HV, VH, VV) Pulse modulation Linear FM chirp Linear FM chirp Linear FM chirp Linear FM chirp Pulse bandwidth (MHz) 8.5 310 310 40 Pulse duration (s) 100 31 33 33 Pulse repetition rate (pps) 650 4 492 1 395 1 395 Duty cycle (%) 6.5 13.9 5.9 5.9 Ran
10、ge compression ratio 850 9 610 10 230 1 320 Antenna type (m) Planar phased array 0.5 16.0 Planar phased array 1.8 3.8 Planar phased array 0.7 12.0 Planar phased array 0.7 12.0 Rec. ITU-R RS.1632 3 TABLE 1 (end) Value Parameter SAR1 SAR2 SAR3 SAR4 Antenna peak gain (dBi) 42.2 42.9 42.7/38 (full focus
11、/beamspoiling) 42.7/38 (full focus/beamspoiling) Antenna median side lobe gain (dBi) 5 5 5 5 Antenna orientation (degrees from nadir) 30 20-38 20-55 20-55 Antenna beamwidth (degrees) 8.5 (El), 0.25 (Az) 1.7 (El), 0.78 (Az) 4.9/18.0 (El), 0.25 (Az) 4.9/18.0 (El), 0.25 (Az) Antenna polarization Linear
12、 horizontal/vertical Linear horizontal/vertical Linear horizontal/vertical Linear horizontal/vertical Receiver front end 1 dB compression point ref to receiver input (dBW) 62 input 62 input 62 input 62 input Allowable density of configuration saturation ref to receiver input 114/54 dBW input at 71/1
13、1 dB receiver gain 114/54 dBW input at 71/11 dB receiver gain 114/54 dBW input at 71/11 dB receiver gain 114/54 dBW input at 71/11 dB receiver gain Receiver input max. power handling (dBW) +7 +7 +7 +7 Operating time (%) 30 the orbit 30 the orbit 30 the orbit 30 the orbit Minimum time for imaging (s)
14、 9 15 15 15 Service area Land masses and coastal areas Land masses and coastal areas Land masses and coastal areas Land masses and coastal areas Image swath width (km) 50 20 16/320 16/320 4 Rec. ITU-R RS.1632 TABLE 2 5.3 GHz typical spaceborne radar altimeter characteristics TABLE 3 5.3 GHz typical
15、spaceborne scatterometer characteristics Jason mission characteristics Lifetime 5 years Altitude 1 347 km 15 km Inclination 66 Poseidon 2 altimeter characteristics Signal type Pulsed chirp. linear FM C band pulse repetition frequency (PRF) 300 Hz Pulse duration 105.6 s Carrier frequency 5.3 GHz Band
16、width (BW) 320 MHz Emission RF peak power 17 W Emission RF mean power 0.54 W Antenna gain 32.2 dBi 3 dB aperture 3.4 Side lobe level/maximum 20 dB Backside lobe level/maximum 40 dB Beam footprint at 3 dB 77 km Interference threshold 118 dBW Parameter Value System name Scatterometer 1 Scatterometer 2
17、 Orbital altitude (km) 780 800 Inclination (degrees) 98.5 98.5 Centre frequency (GHz) 5.3 5.255 Pulse width 70 s (mid) 8 ms (mid) 130 s (fore/aft) 10.1 ms (fore/aft) Modulation Interrupted CW Linear FM (chirp) Transmitter BW (kHz) 15 500 PRF (Hz) 115 (mid) 29.4 98 (fore/aft) Antenna type Slotted wav
18、eguide Slotted waveguide Rec. ITU-R RS.1632 5 TABLE 3 (end) Annex 2 Sharing constraints between spaceborne active sensors and high speed WLANs in the 5 250-5 350 MHz band 1 Introduction This Annex presents the results of three sharing analyses for the band 5 250-5 350 MHz between the spaceborne acti
19、ve sensors and the high speed WLANs, or RLANs. The first study, given in 2 of this Annex, uses high performance RLAN (HIPERLAN) type 1 classes B and C and HIPERLAN type 2 characteristics for the RLANs and uses SAR4 characteristics for the SAR. In this study, it is feasible for the indoor only HIPERL
20、AN type 1 class B and HIPERLAN type 2 to share the 5 250-5 350 MHz band with SAR4, but is not feasible for the HIPERLAN type 1 class C to share the band, nor for any HIPERLAN type designed to be operated outdoors with the technical characteristics assumed in the study. The second study, as given in
21、3 of this Annex, uses three RLAN types, RLAN1, RLAN2, and RLAN3, and uses SAR2, SAR3, and SAR4 characteristics for the SARs. In this study, for the single transmitter deployed outdoors, the RLAN1 high speed WLAN transmitter interference was above the acceptable level for SAR4, the RLAN2 high speed W
22、LAN transmitter interference was above the acceptable levels for both SAR3 and SAR4, and the RLAN3 high speed WLAN transmitter interference was above the acceptable level for SAR4. For indoors/outdoors RLAN deployment, it is feasible for the RLAN1, based on an assumption of only 12 active transmitte
23、rs per km2within the Parameter Value Antenna gain (dBi) 31 (mid) 28.5 (mid) 32.5 (fore/aft) 29.5 (fore/aft) Antenna mainbeam orientation (degrees) Incidence angles: 18-47 (mid) 24-57 (fore/aft) Incidence angles: 25.0-54.5 (mid) 33.7-65.3 (fore/aft) Antenna beamwidth (3 dB), elevation Azimuth beamwid
24、th 24 (mid) 1.3 26 (fore/aft) 0.8 23.6 (mid) 1.1 23.9 (fore/aft) 0.8 Instrument elevation angle (degrees) 29.3 37.6 Antenna polarization Vertical Vertical Transmitter peak power 4.8 kW 120 W Receiver noise temperature (dB) Noise factor: 3 Noise factor: 3 Service area Oceanic and coastal areas, land
25、masses Oceanic and coastal areas, land masses 6 Rec. ITU-R RS.1632 SAR (footprint) and a single frequency channel for the RLAN1, to share with SAR2, SAR3, and SAR4, but it is not feasible for the RLAN2, based on an assumption of 1 200 active transmitters per office space and 14 channels across a 330
26、 MHz band, to share with SAR2, SAR3, and SAR4. For an indoor deployment and considering the interference from the RLAN3 configuration of high speed WLANs to the SARs, the analysis shows that any surface density less than 37-305 transmitters/km2/channel will yield acceptable interference levels into
27、the SAR, depending on the imaging SAR pixel S/N for an imaging SAR. The anticipated mean density is estimated to 1 200 transmitter/large office area and 250 transmitters/industrial area. The anticipated high density assumes 14 channels, each 23.6 MHz wide, over a 330 MHz band. For interference from
28、the RLAN3 configuration of high speed WLANs to the SARs, the analysis shows that only for a surface density less than 518 to 4 270 transmitters/km2over 14 channels, will local area networks (LANs) yield acceptable interference levels into the SAR. For RLAN3 interference into SAR2 and SAR4, this woul
29、d correspond to about 3 to 12 large office buildings or 15 to 60 industrial areas within the SAR footprint, depending on the SAR pixel S/N. The third study, as given in 4 of this Annex, uses the more critical HIPERLAN type 1 characteristics for the RLANs and uses the altimeter characteristics as giv
30、en in Table 2 for the altimeter. The radar altimeter operation with a 320 MHz bandwidth around 5.3 GHz is compatible with HIPERLANs. The fourth study, as given in 5 of this Annex, uses the HIPERLAN type 2 characteristics for the RLANs and uses the scatterometer characteristics as given in Table 3 fo
31、r the scatterometer. The scatterometer operation around 5.3 GHz is compatible with HIPERLANs operated indoors. 2 Study of HIPERLANs types 1 and 2 and SARs 2.1 Technical characteristics of the two systems The technical characteristics of the WLANs used for the sharing analysis are those of the HIPERL
32、AN type 1 and type 2, for which the European Telecommunications Standards Institute (ETSI) in Europe has published the relevant specifications: EN 300 652 for type 1 and TS 101 683 for type 2. For other study parameters (building attenuation, operational activity duty cycle, HIPERLAN density, etc.)
33、the values used are those agreed by ETSI ERM for these studies in Europe. HIPERLAN type 1: It provides high speed RLAN communications that are compatible with wired LANs based on Ethernet and Token-ring Standards ISO 8802.3 and ISO 8802.5. HIPERLAN/1 parameters: e.i.r.p. (high bit rate (HBR), in 23.
34、5 MHz, low bit rate (LBR), in 1.4 MHz): class A: 10 dBm maximum e.i.r.p. class B: 20 dBm maximum e.i.r.p. class C: 30 dBm maximum e.i.r.p. Channel spacing: 30 MHz Antenna directivity: omnidirectional Rec. ITU-R RS.1632 7 Minimum useful receiver sensitivity: 70 dBm Receiver noise power (23.5 MHz): 90
35、 dBm C/I for BER 103at HBR: 20 dB Effective range (class C): 50 m. Only classes B (100 mW maximum e.i.r.p.) and C (1 W maximum e.i.r.p.) are considered for this study. HIPERLAN type 2: It provides high speed RLAN communications that are compatible with wired LANs based on ATM and IP standards. HIPER
36、LAN/2 parameters: e.i.r.p.: 0.2 W (in the 5 250-5 350 MHz band) Channel bandwidth: 16 MHz Channel spacing: 20 MHz Antenna directivity: omnidirectional Minimum useful receiver sensitivity: 68 dBm (at 54 Mbit/s) to 85 dBm (at 6 Mbit/s) Receiver noise power (16 MHz): 93 dBm C/I: 8-15 dB Effective range
37、: 30-80 m. In European countries, in the band 5 250-5 350 MHz, the e.i.r.p. is limited to 200 mW and the use of HIPERLANs is only allowed when the following mandatory features are realized: transmitter power control (TPC) to ensure a mitigation factor of at least 3 dB; dynamic frequency selection (D
38、FS) associated with the channel selection mechanism required to provide a uniform spread of the loading of the HIPERLANs across a minimum of 330 MHz. Currently HIPERLAN/1 does not support these two features. The DFS does not only provide a uniform load spread, but it allows also each HIPERLAN system
39、 to detect interference from other systems and therefore is able to avoid co-channel operation with other systems, notably radar systems. The system senses which channel is free for use and automatically switches to it. This allows large numbers of HIPERLAN systems to operate in the same office envi
40、ronment. It is to be noted that the numbers given in the deployment scenarios are based on the assumption of the availability of a total of 330 MHz band for WLANs. Assuming that this bandwidth will be available in two sub-bands (5 150-5 350 MHz and 130 MHz above 5 470 MHz) and given the channel spac
41、ing and the need to create a guardband at the boundaries of the two sub-bands, the assumed number of channels used in the study is 8 for type 1 and 14 for type 2. 8 Rec. ITU-R RS.1632 Other HIPERLAN parameters used for this study are those agreed by ETSI: average building attenuation towards EESS in
42、struments: 17 dB; active/passive ratio: 5%; percentage of outdoor usage: 15%; deployment scenarios: 1 200 systems for large office buildings, 250 systems for industrial sites. For the spaceborne active sensors are taken from the SAR characteristics in Annex 1 of this Recommendation. The SAR4 type is
43、 taken as example for the analysis of the interference from HIPERLAN into SAR, but similar results can be obtained for the other types. SAR types 2-4 have been used for the analysis of the interference from SAR into HIPERLAN. 2.2 Sharing analysis (from WLAN into SAR) The sharing analysis is given in
44、 Table 4 for the three cases considered: HIPERLAN type 1 (class B and class C) and type 2. Given the expected HIPERLAN density (1 200 systems per large office building and 250 for industrial sites) the outdoor only or mixed indoor-outdoor cases do not represent a feasible sharing scenario for any of
45、 the three cases considered. For the indoor use only, sharing is not feasible for the high power type 1 class C, while the type 1 class B and type 2 cases require further considerations. In fact the 440 systems limit indicated in Table 4 for type 2 indoor only is per channel. Considering the DFS mec
46、hanism described above, one can make the hypothesis that the HIPERLAN type 2 systems can be spread across the 14 channels available, giving a theoretical upper limit of 6 160 systems within the 76.5 km2of the SAR footprint. Type 1 class B gives an upper limit of 5 208 systems. TABLE 4 Permissible ac
47、tive HIPERLAN capacity in channels shared with SAR4 HIPERLAN type Type 1/Class B Type 1/Class C Type 2 Parameter Value dB Value dB Value dB Max transmitted power (W) TPC effect on average 0.1 Not available 10 1 Not available 0 0.2 7 3 Distance (km) and free space loss 425.7 159.5 425.7 159.5 425.7 1
48、59.5 Additional transmit path loss (dB): Outdoor only Indoor only Mixed (15% outdoor) 0 17 7.8 0 17 7.8 0 17 7.8 Antenna gain, transmitter (dB) 0 0 0 Rec. ITU-R RS.1632 9 TABLE 4 (end) These values correspond to roughly five large office buildings in the 76.5 km2of the SAR footprint and, although fa
49、r from being a worst case, can be considered a reasonable assumption for urban and suburban areas. It can therefore be concluded that, although marginally, the two services can share the band when systems with the HIPERLAN type 2 or type 1 class B systems are deployed indoor. The DFS mechanism will provide a uniform spread of the load across the available channels. If the channel selection is not based on a random choice, this hypothesis is likely to be incorrect and the conclusion needs to be
