Performance Analysis of Orthogonal Coded Modulation Based on 6PSK and BPSK in Alerting Channel for GEO Mobile Satellite System

In GEO (Geostationary Earth Orbit) mobile satellite system, subscribers could not be paged when the MES (Mobile Earth Station) is normally out of coverage area due to additional propagation path losses. To alert the subscribers in such situation, a more penetrative and computationally efficient coding modulation is needed. In this paper two kinds of orthogonal coded modulation, which are 6PSK based and BPSK based, are analyzed. Through compared with the common paging channel modulation method, and the performance analysis of them, we conclude that they can increase the SNR (Signal Noise Ratio) of actual transmitted information, which is greatly more than the SNR of data in the common paging channel. To be emphasized, we also confirm the predominance of 6PSK modulation.