1、 Rep. ITU-R BO.2071 1 REPORT ITU-R BO.2071 System parameters of BSS between 17.3 GHz and 42.5 GHz and associated feeder links (2006) 1 Introduction Working Party 6S has identified the need to assemble system parameters and system characteristics for the BSS bands between 17.3 GHz and 42.5 GHz and as
2、sociated feeder links. For that purpose, a Report had been developed on the basis of inputs to ITU-R. An example of the parameters is shown as follows: a) Service requirements service description, service objective, service availability, bit rate, etc. b) Feeder-link parameters feeder-link frequency
3、, earth station e.i.r.p., feeder-link transmitting parameters, etc. c) Modulation, link parameters bandwidth, modulation, coding, polarization, sharing criteria, etc. d) Satellite parameters satellite e.i.r.p. (pfd), transmitting antenna pattern, etc. e) Receiver parameters receiving antenna diamete
4、r, antenna pattern, etc. Further contributions are invited for future updates of this Report, which may eventually serve in establishing system parameters of BSS services operating above 17 GHz, including the associated feeder links. Note that for the specific problem of rain mitigation techniques i
5、n the noted bands, WP 6S developed Recommendation ITU-R BO.1659 Mitigation techniques for rain attenuation for BSS systems in frequency bands between 17.3 GHz and 42.5 GHz. The BSS systems in the frequency bands between 17.3 GHz to 42.5 GHz have the possibility to deliver wideband RF digital multipr
6、ogramme services, which may consist of SDTV, HDTV, audio and data programmes. In addition, it is also possible to implement interactive multimedia and on-demand services. To facilitate the introduction of BSS in the bands, WP 6S/RG 9 was established to carry out studies on applicable technologies to
7、 improve service availability against rain attenuation, and on outlining necessary BSS system characteristics. In the Radio Regulations, the band 17.3-17.8 GHz in Region 2 and the band 21.4-22.0 GHz in Regions 1 and 3 are allocated to BSS as of 1 April 2007. Appendix 1 to Annex 1 to this Report cont
8、ains examples of system parameters of BSS systems and their associated feeder links in frequency bands 17.3-17.8 GHz and 24.75-25.25 GHz, which are allocated for BSS feeder links in Region 2. 2 Rep. ITU-R BO.2071 The system parameters given in Table 1 are based on information supplied by Canada in a
9、ccordance with Appendix 4 of the Radio Regulations (RR). The system parameters given in Table 2 are based on information supplied by the United States of America. Using the system parameters provided in Table 1 and information provided in ETSI DVB-S.1 standard (version EN 301 210 V1.1.1) as the mini
10、mum satellite system link performance requirements, Appendix 2 to Annex 1 contains a study on the impact of satellite separation on system performance of typical BSS systems. Utilizing the same methodology as provided in Appendix 2, Appendix 3 to Annex 1 re-examines the impact of satellite separatio
11、n on system performance for BSS systems using information provided in ETSI DVB-S.2 standard (version EN 302 307 V1.1.1). However, it should be noted that it was assumed in these studies that the downlink and uplink e.i.r.p.s (of both the wanted and interfering networks) were scaled with the C/N thre
12、shold for the type of modulation used regardless of whether the capability exists for both networks. This has simply been done for comparison purposes to illustrate the effect of the type of modulation employed. The actual Appendix 4 of the RR data filed for each network and Article 21 pfd limits wi
13、ll ultimately determine the maximum downlink e.i.r.p. regardless of the C/N threshold for the type of modulation used. The feasibility of using higher order modulation techniques (e.g. higher than 8-PSK) over satellite links remains to be proven in practice. Annex 2 to this Report shows study result
14、s for 21 GHz band broadcasting satellites based on input documents to WP 6S. Measured downlink receiving earth station antenna patterns are shown in 2. Some examples of BSS systems utilizing the locally-variable e.i.r.p. systems in the 21 GHz band are introduced in 3. In 4, a study of antenna radiat
15、ion pattern of a variable e.i.r.p. broadcasting-satellite system in the 21 GHz band is described. Section 5 shows a study result of interference from the locally variable e.i.r.p. satellite systems into a conventional satellite system. Section 6 deals with methodology to evaluate unwanted emission f
16、rom 21 GHz band BSS. Finally, a transmission scheme utilizing the receiver with a storage function is described in 7. Annex 1 System parameters of unplanned BSS systems and associated feeder links in frequency bands 17.3-17.8 GHz and 24.75-25.25 GHz Appendix 1 to Annex 1 Examples of system parameter
17、s of unplanned BSS systems and associated feeder links in frequency bands 17.3-17.8 GHz and 24.75-25.25 GHz Table 1 contains an example summary of the Canadian coordination information submitted to BR (CAN-BSS-95). The system plans to provide TV broadcasting and interactive multimedia services. Furt
18、hermore, coordination information submitted by another Region 2 country for providing broadcast services is included in the third column, titled “Other”, of the Table. Rep. ITU-R BO.2071 3 TABLE 1 System characteristics CAN-BSS-95 Other Orbit GEO GEO Position 95.0 W 101.0 W Uplink 24.75-25.25 GHz 24
19、.75-25.25 GHz Frequency Downlink 17.3-17.8 GHz 17.3-17.8 GHz Broadcast Coverage North America North America Assigned channel bandwidth 25 MHz 25-500 MHz Uplink Satellite receive antenna gain 35 dBi 49.4 dBi E.S. transmit antenna size 5.6 m, 3.5 m 5-13 m E.S. transmit antenna gain (maximum) 61.1 dBi,
20、 57.0 dBi 60.5-68.8 dBi Receiving satellite system noise temperature 730 K 810 K E.S. transmit antenna pattern AP 4 A, B, C, D, parameters: 29, 25, 32, 25, 7 Rec. ITU-R S.465 Polarization Circular left Circular left Maximum power supplied to the input of E.S. transmitting antenna 22.2 dBW 21.2-29.5
21、dBW Downlink Satellite transmit antenna gain 35 dBi 49.4 dBi E.S. receive antenna size 0.45-1.4 m 0.45-1.2 m E.S. receive antenna gain 36.1-46.0 dBi 36.5-45.0 dBi Polarization Circular right Circular right E.S. receive noise temperature 170 K 140 K E.S. receive antenna pattern (see Attachment 1 to A
22、ppendix 1) Rec. ITU-R S.465 Maximum power supplied to the input of satellite transmitting antenna 22.2 dBW 14.8-19.1 dBW Eb/N06.5 dB No info. C/N threshold 6.6 dB No info. Required C/N (clear-sky) 9.0 dB Uplink 17.4 dB, Downlink 6-17.6 dB Multimedia (CAN-BSS-95 only) Forward link Coverage Visible ea
23、rth Channel bandwidth 25 MHz Uplink Satellite receive antenna gain 44.5 dBi E.S. transmit antenna size 5.6 m, 3.5 m 4 Rep. ITU-R BO.2071 TABLE 1 (continued) CAN-BSS-95 Other E.S. transmit antenna gain (maximum) 61.1 dBi, 57.0 dBi Receiving satellite system noise temperature 730 K E.S. transmit anten
24、na pattern AP 4 A, B, C, D, parameters: 29, 25, 32, 25, 7Polarization Circular left Maximum power supplied to the input of E.S. transmitting antenna 18.0 dBW Downlink Satellite transmit antenna gain 44.5 dBi E.S. receive antenna size 0.45-1.4 m E.S. receive antenna gain 36.1-46.0 dBi Polarization Ci
25、rcular right E.S. receive noise temperature 170 K E.S. receive antenna pattern (see Attachment 1 to Appendix 1) Maximum power supplied to the input of satellite transmitting antenna 21.0 dBW Eb/N06.5 dB C/N threshold 6.6 dB Required C/N (clear-sky) 11.0 dB Return link Coverage Visible earth Channel
26、bandwidth 55 MHz, 113 MHz Uplink Satellite receive antenna gain 44.5 dBi E.S. transmit antenna size 0.45-1.4 m E.S. transmit antenna gain (max) 39.2-49.1 dBi Receiving satellite system noise temperature 730 K E.S. transmit antenna pattern Rec. ITU-R S.465 Uplink polarization Circular left, circular
27、right Maximum power supplied to the input of E.S. transmitting antenna 36.4 dBW, 39.7 MHz Downlink Satellite transmit antenna gain 44.5 dBi E.S. receive antenna size 5.6 m, 3.5 m E.S. receive antenna gain 58.0 dBi, 54 dBi Downlink polarization Circular right, circular left E.S. receive noise tempera
28、ture 185 K E.S. receive antenna pattern AP 4 A, B, C, D, parameters: 29, 25, 32, 25, 7 Maximum power supplied to the input of satellite transmitting antenna 21.2 dBW Rep. ITU-R BO.2071 5 TABLE 1 (end) CAN-BSS-95 Other Eb/N06.5 dB C/N threshold 6.6 dB Required C/N (clear-sky) 10.0 dB Table 2 contains
29、 parameters of another example system that could operate in the 17.3-17.8 GHz and 24.75-25.25 GHz bands. The system has a reconfigurable “bent-pipe” payload capable of providing TV broadcasting services using fixed beams over North and South America, respectively, or a steerable beam over North Amer
30、ica. TABLE 2 Additional system characteristics HDBSS-A (NAF) HDBSS-A (SAF) HDBSS-A (NAS) Orbit GEO GEO GEO Position 67.5 W 67.5 W 67.5 W Uplink 24.75-25.25 GHz 24.75-25.25 GHz 24.75-25.25 GHz Frequency Downlink 17.3-17.8 GHz 17.3-17.8 GHz 17.3-17.8 GHz Coverage North America South America North Amer
31、ica Assigned channel bandwidth 24 MHz 24 MHz 48 MHz Uplink Satellite receive antenna gain 37 dBi 34.2 dBi 46.1 dBi E.S. transmit antenna size 6-11 m 6-11 m 6-11 m E.S. transmit antenna gain (maximum) 61.1-67 dBi 61.1-67 dBi 61.1-67 dBi Receiving satellite system noise temperature 815 K 815 K 865 K E
32、.S. transmit antenna pattern Rec. ITU-R S.465 Rec. ITU-R S.465 Rec. ITU-R S.465 Polarization Circular left/ circular right Circular left Circular left Maximum power supplied to the input of E.S. transmitting antenna 13.5-20 dBW 13.5-20 dBW 13.5-20 dBW Downlink Satellite transmit antenna gain 34.5 dB
33、i 30.9 dBi 46.1 dBi E.S. receive antenna size 0.45-1.8 m 0.45-1.8 m 0.45-1.8 m E.S. receive antenna gain 36.1-48.1 dBi 36.1-48.1 dBi 36.1-63.9 dBi Polarization Circular right circular left Circular right Circular right 6 Rep. ITU-R BO.2071 TABLE 2 (end) HDBSS-A (NAF) HDBSS-A (SAF) HDBSS-A (NAS) E.S.
34、 typical G/T 12.3-24.3 dB/K 12.3-24.3 dB/K 12.3-24.3 dB/K E.S. receive antenna pattern (For off axis angles up to 20) Rec. ITU-R S.465Rec. ITU-R S.580 Rec. ITU-R S.465 Rec. ITU-R S.580 Rec. ITU-R S.465Rec. ITU-R S.580 Maximum power supplied to the input of satellite transmitting antenna 21.1 dBW, 23
35、.7 dBW 21.1 dBW, 23.7 dBW 18.6 dBW Eb/N02.9 dB 2.9 dB 4.9 dB C/N threshold 4.1 dB 4.1 dB 8.9 dB Required C/N (clear-sky) 5.6 dB 5.6 dB 10.4 dB Attachment 1 to Appendix 1 Reference receiving antenna pattern Antenna pattern: Gco() = Gmax= 2.5 1032Dfor 0 mwhere m= 0025.01GGDmaxGco() = G1= 29 25 log10rf
36、or m rwhere r= 95 DGco() = 29 25 log10 for r 7 Gco() = 7.9 dBi for 7 9.2 Gco() = 32 25 log10 for 9.2 48 Gco() = 10 dBi for 48 180 where: Gco:co-polar gain (dBi) Gmax: maximum isotropic gain of the antenna (dBi) : off-axis angle (degrees) D antenna diameter (m) : wavelength (m). Rep. ITU-R BO.2071 7
37、Reference receiving antenna pattern Appendix 2 to Annex 1 A study of orbital separation requirements for the unplanned BSS and associated feeder links in frequency bands 17.3-17.8 GHz and 24.75-25.25 GHz 1 Introduction This Appendix examines the impact of satellite separation (intersystem interferen
38、ce) on system performance of typical BSS systems operating in frequency bands 17.3-17.8 GHz and 24.75-25.25 GHz. 2 Methodology The system performance is represented by the system margin, which is defined as: thresholdfadedsystemNCINC+=,marginSystem where: :, fadedsystemINC+overall system + INCwith u
39、plink availability of 99.95% of the year and the downlink availability of 99.8% of the year 8 Rep. ITU-R BO.2071 +=BWRNENCbbthresholdlog100+=BWFBWRSFECMLBWNEblog100+=BWFRSFECMLNEblog100and Rb: bit rate (Mbit/s) BW: channel bandwidth (MHz) ML: modulation level, e.g. 2 for QPSK and 3 for 8-PSK FEC: FE
40、C rate RS: Reed-Solomon coding rate BWF: bandwidth shaping factor (roll-off factor). The analysis was performed for two types of interfering systems: homogeneous and inhomogeneous. For the inhomogeneous case, interfering systems with different modulation schemes from the wanted system were examined.
41、 Both QPSK and 8-PSK modulation schemes were examined using different FEC rates in order to assess the sensitivity of the satellite separation requirements on these parameters. 2.1 Assumptions The system characteristics used in the analysis are listed in Attachment 1 to Appendix 2. They are largely
42、based on the attachment to Annex 11 of the March 2003 WP 6S Chairmans Report. The analysis was carried out on the following assumptions: a) The interfering satellites are located with equal spacing on both sides of the wanted satellite. Both first and second adjacent interfering satellites were assu
43、med. Co-coverage is assumed for wanted and interfering satellites. b) Recommendation ITU-R P.618-8 was used to calculate propagation attenuation. The uplink availability is assumed to be 99.95% of the year and the downlink availability is assumed to be 99.8% of the year; this results in an overall s
44、ystem availability of 99.75% of the year. c) Recommendation ITU-R BO.1212 was used to calculate the total interference. d) The receiving earth station is located in rain climatic zone “M”. (Rain rate = 72.4 mm/h exceeded for 0.01% of the average year.) e) The wanted and interfering uplink earth stat
45、ions were assumed to be in the same location, as this represents the worst-case scenario. f) The minimum required link performance is obtained from ETSI standard EN 301 210 V1.1.1. (DVB; Framing structure, channel coding and modulation for DSNG and other contribution applications by satellite.)11It
46、is noted that ETSI standard EN 301 210 V.1.1.1 will be updated in the near future. Pending on the updated values, the results presented in this document might be changed. Rep. ITU-R BO.2071 9 3 Results 3.1 Homogeneous model for interfering system based on wanted system Case 1: using QPSK modulation
47、Analysis was performed to examine the relationship between system performance and satellite spacing for one pair and two pairs of interfering satellites. It is assumed that an FEC rate of 3/4 is used. The results of the analysis are shown in Fig. 1. FIGURE 1 System margin vs. satellite spacing for s
48、ystem using QPSK In order to study the effect of FEC rate on the system performance, an analysis was performed to determine the relationship between system margin and satellite spacing for systems with various FEC rates. Figure 2 shows the analysis results, which are based on two pairs of interferin
49、g satellites. 10 Rep. ITU-R BO.2071 FIGURE 2 System margin vs. satellite spacing for various FEC rates Case 2: using 8-PSK modulation A similar analysis was performed for systems using 8-PSK modulation and an FEC rate of 2/3. It is expected that, due to change in the modulation scheme, the transmitting satellite power (downlink power) and the transmitting earth station power (uplink power) have to be increased. It is determined that the
