Balancing closed and open loop CSI in mobile satellite link adaptation

Abstract

We consider the problem of modulation and coding scheme selection in the return link of a mobile satellite system. We propose to use a weighted combination of both open loop and closed loop signal quality indicators to perform this selection. The combination weights are not selected by making any assumptions on the channel distribution; instead, they are dynamically adapted according to the ACK/NAK exchange between both ends. This adaptation procedure is obtained as a stochastic programming solution to an optimization problem. Numerical results will show the good performance of the proposed method compared to previous algorithms, and its robustness to environment changes.