Adaptive HPA Back-Off algorithm for interactive mobile satellite broadcasting system

Abstract

In order to solve the problem of introducing additional Total Degradation (TD) in adaptive satellite system caused by fixed High Power Amplifier (HPA) operating point, the paper proposes an adaptive HPA Input Back-Off (IBO) algorithm carried out on the gateway side in the Forward Link of the system based on Adaptive Coding and Modulation (ACM) techniques. On the other hand, the traditional way of evaluation of system-level TD would cause inaccurate assessment if used in adaptive forward link satellite system, so Dynamic Real-Time Total Degradation (DRTTD) is proposed to evaluate overall system performance. Results show that, with the adaptive HPA IBO algorithm adopted, the whole system can obtain system-level DRTTD performance better. This indicates that more appropriate integral HPA's operating point can be obtained in the adaptive forward link of the interactive mobile satellite broadcasting system with the proposed adaptive HPA IBO algorithm than traditional fixed HPA's working status situation.