Code division access and switching for multibeam satellite communications

A code division access and switching method is applied to multibeam satellite fixed service communications. The access scheme is based on a spectrally efficient CDMA (SE-CDMA) while the onboard routing is based on code division switching (CDS). In this article we present the system architecture of the SE-CDMA and CDS, and evaluate the bit error rate performance of the end-to-end connection link. The CDS is a non-blocking switch with complexity linearly proportional to its size which can route calls from an uplink to a downlink beam without onboard demodulation or channel decoding. The SE-CDMA can achieve very low bit error rates at low signal to noise ratio, while it allows frequency reuse one (i.e., reuse of the available spectrum in every beam).