ANALYSIS OF A RAIN COMPENSATION ALGORITHM FOR K KA-BAND COMMUNICATIONS/

A rain compensation algorithm (RCA) has been developed for use in the advanced communications technology satellite (ACTS) mobile terminal (A MT) system. The basic goal of the RCA is to control the transmitted da ta rates (9.6, 4.8 or 2.4 kbps) in the forward and return links so tha t a 3 dB link margin is maintained at the highest possible transmitted data rate. In this paper, analyses of both theoretical and practical issues relating to the RCA are presented. In addition, sample simulati ons of a one-dimensional version of the RCA at the MT are presented wh ich illustrate typical RCA performance using both simulated and record ed pilot fade field data. It is found that with suitable post-processi ng, the RCA can provide reasonable (conservative) data rate estimates without making excessive data rate changes, i.e., data rate change flu ctuations. It is anticipated that the results presented here will not only be useful for the eventual operation of the RCA, but more general ly will be useful in the design and operation of other rain compensati on techniques for K/Ka-band communication systems.