Analysis of the interference due to differential rain attenuation induced by an adjacent terrestrial microwave system on a double‐site diversity Earth‐space system

Abstract

Abstract. One of the main propagation effects on interference between a satellite system and an adjacent microwave terrestrial path is the differential rain attenuation. In this paper a method to predict rain differential attenuation statistics, used for single-site interfered Earth-space systems, is extended to include double-site diversity systems. The modified method is again based on a model of convective rain cells as well as on the lognormal assumption for the point rainfall rate distribution at the location under consideration. Numerical results are presented concerning a realistic interfered satellite link using double-site diversity and located in Japan. Because of a lack of available experimental data, our attention has mainly been concentrated on the examination of the optimum coordination between the adjacent systems. Some very useful conclusions are deduced.

Prediction of the Differential Rain Attenuation Induced by an Adjacent Terrestrial System on a Site-Diversity Satellite System Using Frequency Re-Use

“…In expression (7), (C=I) i;o corresponds to the con guration where the interfering transmitter antenna is considered to point directly at the Earth station. The evaluation of the probabilities (1){(3) follows the same general considerations as those for the respective single polarization problem [11]. As a matter of fact, the joint exceedance probabilities appearing in expressions (2){(3) can be evaluated as:…”

“…The analytic form for the two-dimensional normal density function f U1 U2 (u 1 ; u 2 ) as well as for the parameters · ; ¼ ; · 3=1:2 ; · 4=1:2 ; ¼ 3=1:2 , ¼ 4=1:2 which correspond to the proper conditional mean values and standard deviations, can be found in [11,13]. In the expressions (24){(29), A m1 and S a1 are the lognormal statistical parameters of the attenuations y (The Pascal code concerning the numerical calculation of the multidimensional integrals can be obtained by sending a request to the leading author by e-mail at ikanell® acc.ece.ntua.gr) A 0 C1 and A 0 C2 , given elsewhere [9]:…”

“…After using a straightforward statistical analysis, similar to that used in [11], the integrals of (13){ (15) can be transformed to the following simpli ed forms y…”

“…The lognormal statistical parameters A m1 ; S a1 ; A m2 ; S a2 and A 0 m2 ; S 0 a2 ; encountered in the previous relationships, can be evaluated by using expressions (30){(34). Finally, the expressions for the statistical parameters · ; ¼ ; · 3=1:2 ; · 4=1:2 ; ¼ 3=1:2 and ¼ 4=1:2 are given elsewhere [11,13].…”

“…The predictive procedure has been compared with the only available set of data taken from Yokosuka, Japan [10]. As a next step, the case of interfered Earth space systems using double site diversity has recently been examined [11]. As pointed out above, the direct need for using very large availability time speci cations in combination with existing heavy rain climatic conditions imposes the use of the latter countermeasure technique.…”