1、 Rec. ITU-R SF.1707 1 RECOMMENDATION ITU-R SF.1707 Methods to facilitate the implementation of large numbers of earth stations in the FSS in areas where terrestrial services are also deployed (2005) Scope This Recommendation provides methods and means to facilitate the implementation of large number
2、s of earth stations operating in the fixed-satelllite service (FSS) in areas where terrestrial services are also deployed. It includes examples for the deployment of a large number of FSS earth stations, guidance for an agreed interference calculation to facilitate implementation of such large numbe
3、rs of earth stations, and an example of how to develop a single transmit and a single receive coordination distance for consideration as a means to ease bilateral agreements for a given geographical area. The ITU Radiocommunication Assembly, considering a) that an increasing number of fixed-satellit
4、e service (FSS) network applications, operating in certain FSS bands, plan to deploy large numbers of earth stations; b) that these FSS networks are subject to coordination under various provisions of the ITU Radio Regulations (RR); c) that in some frequency bands above 17 GHz, allocated to the FSS,
5、 administrations may consider various options to facilitate establishing FSS systems which will provide broadband services to a large number of earth stations; d) that the deployment of large numbers of FSS earth stations is most suitable in frequency bands not shared with terrestrial services in th
6、e same geographic area, but that in some bands there will be sharing between FSS earth stations and terrestrial stations in some areas; e) that there may be a need to facilitate the implementation of such services involving the coordination/registration of large numbers of FSS earth stations in area
7、s where terrestrial services are also deployed in the same frequency band; f) that a number of FSS systems with types of earth stations and characteristics other than those used by systems with large numbers of earth stations have already been brought into use or are planned to be brought into use,
8、noting a) that, in shared bands, the use of interference mitigation techniques by the fixed service (FS) and FSS may reduce the number of cases where interference between FS and FSS occurs, recommends 1 that the elements in Annex 2 may be used as guidance for an agreed interference calculation which
9、 may be used to facilitate the implementation of large numbers of earth stations and terrestrial FS stations in the same band for the cases described in Annex 1 (see Notes 1 and 2); 2 Rec. ITU-R SF.1707 2 that a single transmit and a single receive coordination distance for the case of coordination
10、of large numbers of similar earth stations (see Note 3) could be considered for use by administrations as a means to facilitate bilateral agreements for a given geographical area; 3 that the following Notes should be considered as a part of this Recommendation. NOTE 1 The examples in Annex 1 make us
11、e of databases containing technical and geographical information for FSS earth stations and FS stations, and appropriate agreed-upon interference computation programs, to allow the guidelines to be implemented. NOTE 2 In addition to the examples in Annex 1, FSS systems communicated to the Radiocommu
12、nication Bureau which have been coordinated on a site-by-site basis, with types of earth stations and characteristics other than those used by high-density systems, should also be taken into account. NOTE 3 Annex 3 provides an example of a parametric analysis using RR Appendix 7 for development of a
13、 single coordination distance applicable to a particular geographic area. The calculations use a representative set of earth station characteristics. The results of this analysis suggest that it may be possible to arrive at a single transmit and single receive coordination distance beyond which coor
14、dination between FSS earth stations and FS stations would not be required. Such a coordination distance could be used to reduce the number of calculations required under a simplified coordination methodology. The distance will vary depending on frequency, station characteristics, and the particular
15、geographic area. It is noted that administrations have to agree on earth station characteristics to be considered for each case of coordination. NOTE 4 Given that the methods considered in this Recommendation rely upon databases containing the specific locations of FS and FSS stations, this Recommen
16、dation is not meant to apply to those cases where the FS has been authorized on an area basis. Annex 1 Examples for the deployment of large numbers of FSS earth stations 1 Introduction In recent years, it has been recognized that a number of FSS systems currently being planned or developed will like
17、ly encompass a very large number of earth stations. FSS systems will find ideal conditions for deployment in bands where there is no FS allocation since in these bands no coordination between FSS earth stations and FS stations is required. However, many FSS systems are planned for deployment in band
18、s where there is an FS allocation in the ITU Table of Frequency Allocations. These FSS networks are subject to coordination under various provisions of the RR. The objective of this Annex is to provide descriptive examples of how to ease the regulatory procedures associated with the deployment of la
19、rge numbers of earth stations through a simplification in the coordination/registration process. In addition, this Annex provides an example of the methodology that can readily be adapted to different specific conditions. Three different deployments of large numbers of earth stations are addressed:
20、1. national coordination/registration; 2. coordination/registration within a bilateral agreement between two administrations; 3. international coordination/registration in accordance with the RR. Rec. ITU-R SF.1707 3 For each of these three deployments, there are two interference situations to be co
21、nsidered: interference from an FS station to a receive FSS earth station; and interference from a transmit FSS earth station to an FS station. 2 Frequency bands As noted above, the deployment of large numbers of earth stations in FSS frequency allocations can best be carried out in bands that are no
22、t shared with terrestrial services. The methodology presented here is intended to apply to bands shared with the FS, e.g. in various frequency bands allocated to the FSS. An examination of FSS allocations indicates that some are shared with terrestrial services, in particular the FS, and some alloca
23、tions are not. 2.1 Bands not shared with FS In the case where large numbers of FSS earth stations operate in bands not shared with FS these bands are still shared with other FSS systems, so FSS earth stations with other types of technical characteristics must continue to be accommodated. Since such
24、bands are not shared on a co-primary basis with FS, no issues arise with respect to individual site coordination of FSS earth stations. 2.2 Bands shared with FS It is expected that deployment of large numbers of FSS earth stations will take place in various bands shared with the FS. To deploy large
25、numbers of FSS earth stations in bands shared with terrestrial services requires techniques and methods that ensure that mutual unacceptable interference is avoided. In areas where there is already heavy deployment of FS links, it may become difficult to site FSS earth stations. In any case, the met
26、hodology described in 3 of this Annex addresses the situation where the band is shared with FS. 3 Deployment of FSS earth stations This section describes a methodology to facilitate implementation of large numbers of earth stations associated with FSS systems. Administrations and/or satellite operat
27、ors will need to take necessary steps to identify the frequency bands and associated geographical areas where this method would be implemented. 3.1 Deployment of receive FSS earth stations in country “A” 3.1.1 Coordination/registration within individual countries This section provides an example of
28、simplified coordination/registration for the case where FS stations exist in country A, or there are plans for deploying them in the future, and that administration wishes to ensure protection of its receive FSS earth stations. This case includes four steps: Step 1: Identification of FS transmitting
29、 stations: The identification of FS stations that can potentially cause interference to the FSS earth station would be based on a search of a particular administrations database containing details (see Annex 2) of such transmit FS stations and on application of an interference computation program. 4
30、 Rec. ITU-R SF.1707 Step 2: Detailed national coordination, if required: If the FSS operator finds, upon applying an agreed interference computation program or other desired interference analysis tools, that potential unacceptable interference may be caused to the FSS earth station by the FS station
31、s identified in Step 1, then detailed coordination with the operator(s) of the potentially interfering FS station(s) must be conducted. If operation of the receive FSS earth station at a location under consideration or at any other suitable location is not feasible, no FSS service can be provided to
32、 that location in that frequency band. Step 3: Registration of the new FSS earth station: Registration of the new FSS earth station (i.e. addition of this earth station to the national database of receive earth stations) in order to ensure that future FS stations will take it into consideration can
33、only occur upon successfully completing application of the agreed interference computation program, or upon successful conclusion of detailed coordination. Step 4: Future protection of the receive FSS earth station: As new transmit FS stations are to be deployed, the FS operator, based on a pre-agre
34、ed interference computation program, determines whether there is potential for causing unacceptable interference to any of the FSS receive earth stations in the database of a particular administration. An example of how the four steps in the methodology could be implemented is given in Attachment 1
35、to Annex 1. This national coordination/registration is feasible only if there is available a reliable database (all transmit FS stations and receive FSS earth stations in the band under consideration) and a pre-agreed interference computation program to determine whether the transmit FS station can
36、be deployed. In Step 1 of the process, the FSS operator may elect to use the agreed interference computation program that is required for Step 4, however this is not mandatory. The FSS operator has the freedom to be more or less conservative at this stage of the process because, if unacceptable inte
37、rference caused by any of the pre-existing FS stations does occur after the earth station is installed, the responsibility for any measures required to mitigate interference problems from these pre-existing FS stations lies entirely with the FSS operator. On the other hand, in Step 4 agreement on an
38、 interference computation program becomes essential. If, after an FSS earth station is registered, unacceptable interference from an FS station subsequently deployed is observed, it is critical to determine the technical basis on which the FS station was deployed. This can only be done if an interfe
39、rence computation is agreed. If the FS station was installed after verifying that the agreed interference computation was successfully employed, the interfered with FSS operator has the responsibility to remedy the situation. On the other hand, if the FS station was deployed in violation of the agre
40、ed interference computation, the FS station operator would need to immediately take steps to reduce the interference to levels that are compliant with the agreed computation program. The agreed interference computation program should rely extensively on existing ITU-R Recommendations. 3.1.2 Bilatera
41、l coordination/registration This section provides a description for the case of an operator wanting to deploy a receive FSS earth station in country A and wanting to address the potential interference that a transmit FS station in another country can cause to this earth station. One possible path fo
42、r this operator to follow is to request its administration to conduct coordination and registration of this earth station as prescribed in the RR (see 3.1.3 of this Annex). Rec. ITU-R SF.1707 5 Another possible path calls for the establishment of bilateral agreements between the administration of co
43、untry A and the administrations of those countries with whom ITU coordination is triggered. For instance, if country B is one of these countries, A and B would implement a bilateral agreement that basically prescribes that deployment of receive FSS earth stations in country A and of transmit FS stat
44、ions in country B should follow the steps of the simplified coordination/registration described in 3.1.1 of this Annex. In this case, the database of FSS earth stations and FS stations would be common to countries A and B (or at least be available to both countries) and the interference computation
45、program would have to be agreed between countries A and B. In order for receive FSS earth stations to be deployed in country A according to this simplified coordination/registration approach, bilateral agreements with several countries may be required. For most receive FSS earth station locations it
46、 would be expected that only one of these bilateral agreements would have to be used, although more than one agreement might have to be used for some specific earth station locations within country A. 3.1.3 Coordination/registration according to RR provisions If country A has established bilateral a
47、greements with all countries that have FS transmit stations with the potential of causing interference to FSS receive earth stations in country A, there is no need for ITU registration of receive FSS earth stations deployed in country A. However, if country A so wishes, this registration could still
48、 be done. The assumption here is that a country that would have to be involved in the ITU coordination of a specific receive FSS earth station in country A already has a bilateral agreement addressing such coordination with country A. 3.2 Deployment of transmit FSS earth stations in country “A” 3.2.
49、1 Individual country coordination/registration This section provides an example of simplified coordination/registration for the case where FS stations exist in country A, and that administration wishes to ensure protection of existing receive FS stations from its transmitting FSS earth stations. This case also includes four steps: Step 1: Identification of potentially affected FS receive stations: In this step the FSS operator relies on a particular administrations database containing details (see Annex 2) of receive FS stations and uses a pre-agreed interference computation pr
