1、STD-CEPT TIR 01-03 E-ENGL 19BB H 232611111 OOL115bb O29 TIR 01-03 E Distributan: i3 p,w 1 Recommendation T/R 01-03 (Brussels 1980) MONITORING OF SATELLITE TRANSMISSIONS Recommendation proposed by the ”Radiocommunications” Working Group TIWG 3 (R) Text of the Recommendation adopted by the “Telecommun
2、ications” Commission: “The European Conference of Postal and Telecommunications Administrations, considering (a) that from the point of view of emissions monitoring, there is a dierence between operational monitoring of a particolar satellite system and the more general monitoring of the use of the
3、frequency spectrum and of cases of interference between dierent systems or semices, ) that various interference paths may be seen depending on the configuration of the space or terrestrial communication systems in existence, (c) that all cases in which at least one space or earth station causes inte
4、rference or is affected by intexference fall within the scope of a sateIlite transmission monitoring system, (a) that the provision recommended in letter (a) of Recommendation T/R 01-02 (Interlaken 1968, revised in The Hague 1971) does not exclude the possibility of sharing the work/task of monitori
5、ng between the various Administrations so as to achieve more effective control, (e) having noted moreover that information on this matter is available in the documentation of the CCIR, recommends 1. that the main functions to be assigned to a satellite iransmission monitoring system should be as fol
6、lows: 1.1. to detect and identify the causes of interference should stations in space radiocommunications be 1.2. to check the operating and tedinical Characteristics of the emissions in cases mentioned in the above 1.3. to observe and record the conditions of occupancy of the fiequency bands assign
7、ed, on whatever basis, involved, paragraph, to space radiocommunications senices, 2. that a monitoring station required to participate in such a system should as far as possible be capable of taking the following measurements: 2.1. measurement of frequencies, 2.2. identification of the type of signa
8、l and measurement of the modulation characteristics, 2.3. measurement of bandwidths and analysis of the spectral composition of the emissions, 2.4. measurement of the power flux density, 2.5. identification of polarisation, 2.6. determination of the position of the source of the radiation measured,
9、Edition of September 15,1988 - - STDmCEPT T/R 01-03 E-ENGL 19BB 2326414 0014567 Tb5 M TIR 01413 E Page 2 that in the first instance, measurements shouid be taken in the frequency bands indicated in Annex I, since for economic reasons it wi not initiaiiy be possible to conduct measurements throughout
10、 the entire frequency spectrum. For various reasons, Administrations will not be in a position to equip their measuring installations to cover all the frequency bands mentioned in Annex I. The CEPT Administrations should therefore harmonise their plans to equip their monitoring stations, and the act
11、ivities of these stations, in such a way that it will be possible to make all the necessary measurements in ali the frequency bands concerned, that stations responsible for monitoring satellite transmissions should have access, in the most effective form, to ail available information to date on spec
12、trum occupancy in those bands allocated, on whatever basis, to space communications and in adjacent bands, To this end, stations monitoring terrestrial communications &ouid make available to stations monitoring satellite communications, at their request, any information at their disposal in the abov
13、e-mentioned fields. In addition, stations for which CER Administrations are responsible and which are operating in the context of such a system should exchange the information at their disposai concerning stations involved in space communications, 5. that measurements be carried out under the condit
14、ions specified in Annex n.“ Editionof September 15,1988 STDmCEPT TIR 01-03 E-ENGL 1988 232b414 0034556 9TL I TIR 01-03 E page 3 Annex I FREQUENCY BANDS (see No. 3. of Recommendation) 136 149 9 399.9 460 1,500 2,000 3,400 10.95 to 138 to 151 to 402 to 470 to 1,800 to 2,700 to 4,200 to 12.75 MHZ MHZ M
15、HZ MHZ MHZ MHZ MHZ GHZ To have receivers with the necessary sensitivity, the wider of the above mentioned bands will probably have to be subdivided. Edition of September 15,1988 1. 2. 3. 4. 5. 6. STD*CEPT T/R 01-03 E-ENGL 3988 M 2326434 00345b9 838 6 T/R 01-03 E Page 5 Annex II CONDITIONS TO BE COMP
16、LIED WITH FOR MEASUREMENT (see No. 5 of Recommendation) Measurement of frequencies Equipment intended for measuring the transmission frequencies of space stations and earth stations must have an accuracy of at least The accuracy which can be achieved in practice depends largely on the existence of a
17、 characteristic fequency in the spectrum of an emission. As regards the measurement of the frequencies of satellites in near-Earth orbit, emissions from which are consequently liable to be affected at the point of reception, by the Doppler effect, determination of the effective transmission frequenc
18、y can only be achieved by recording and evaluating the Doppler curve. Identification of the class of emission and measurement of the modulation characteristics Each Administration will decide the extent of the equipment which it will install h its satellite transmksion monitoring station for the pur
19、pose of identifying the class of emission and measuring the modulation characteristics. Given the diversity of these characteristics, particuhly in the case of highly complex transmission systems, no values for measurement accuracy are specified. Measurement of bandwidths and analysis of the spectra
20、l composition of emissions The bandwidth of space station emissions is measured by application of the relevant CCIR Recommendations. If the Doppler effect is present, the possible influences of this effect must be included in the value of the indicated bandwidth. It is advisable to hdkate separately
21、 the portion of bandwidth which is a function of this Doppler effect. Measurement of the power flux density It must be possible to determine the power flux density with an accuracy of at least f 3 dB, although an accuracy of _+ 2 dB is desirable would be preferable. Identification of polarisation: (
22、a) Geostationary space stations and earth stations For the identification of polarisation, the receiving antenna of the satellite transmission monitoring station should make it possible to select the following types of polarisation: left handed, right handed and linear. In the case of linear polaris
23、ation, the piane of the oscillation vector should be adjustable. (b) Satellite in near-Earth orbit In this case, the constraints described under (a) are regarded as a minimum. Moreover, it is desirable to have an installation making it possible to measure and indicate the polarisation characteristic
24、s on a continuous basis. Determination of the position of the source of the radiation measured Determination of the position of geostationary space stations and space stations in near-Earth orbit can only be achieved by recording the tracking angles relative to the antenna axes (azimuth, elevation)
25、as a function of time. Determining position on the basis of these angles is a mathematical problem. Edition of September 15,1988 The following table shows, for certain frequencies, the minimum accuracy of measurement of tracking angle to be achieved for each of the two antenna axes Frequency (GHz) 6
26、 Accuracy of measurement of tracking angles 1.5 2.5 4 12 1.4 0.84“ 0.52“ 0.17“ Io.14 d.08“ 10.05“ Io.02“ The values indicated in the above table are calculated on the basis of the following relationship: Accuracy of measurement of tracking angles: O. 1 x 6 in which 6 is the angular opening (at mediu
27、m power) of an antenna with a 1Om parabolic reflector with an efficiency of 50%. Considering that although the values for accuracy of measurement specified above do in fact make it possible to monitor the station-keeping accuracy of _+ 1“ requhed by the Radio Regulations, a reduction of this toleran
28、ce to $r 0.1 is planned, Administrations should endeavour if at all possible to improve the tracking angle measurement results. Edition of September 15,1988 T/R 01-09 Monitoring of satellite transmissions Adm I Imp1 I Remarks 1 AUT I No SUI SVN TUR I I GRC I Planned I A No No No No satellite monitoring stations available No satellite monitoring stations planned No satellite monitoring stations available
