Radiometeorological data for VSAT system planning applications

Abstract

Satellite communications for data and voice services on and from the territory of the CIS is of vital importance to both the growth of economy as well as to the standard of living of their people. Depending on the kind of service, various degrees of quality may be required and offered. The availability of a satellite link at Ku-band frequencies and above is largely affected by rain attenuation. The same is true also for its economy which depends on the link margin required, the antenna size and the transmitter power necessary to cope with the adverse effects of rain. Service providers, therefore, need a detailed knowledge of the frequency of occurrence and the magnitude of propagation effects. Since 1992, the Radio Research and Development Institute (NIIR) co-operates with Deutsche Telekom AG in the field of satellite propagation research. From these studies, we present first findings of the analysis of rain data obtained so far. We also compare attenuation predictions based on local rain rate data with those obtained on the basis of ITU-R Recs. 837 [1] and 618 [2]. It will be shown that it is advisable to use long-term local rain data for system planning in order the customer can be assured that he receives his service at the lowest possible cost. With a view to potential future wide-band satellite systems which will operate at Ka-band, results so far obtained are promising that at least in parts of the Russian Federation they could be operated with reasonable quality.