Transmission of SDH signals through satellite channels using 8-ary PSK technique

The authors discuss the possibility of transmitting synchronous digital hierarchy (SDH) signals through two-link nonlinear satellite channels. Transmitting such high bit rate signals using the standard 72 MHz transponder bandwidth requires the use of high level modulation schemes. The techniques and technologies needed to make the use of 8-ary PSK transmission feasible for future satellite communication systems are examined. The authors show that it is possible to transmit a synchronous transport module-level 1 (STM-1) signal using 8-ary PSK transmission, for the 6/4 GHz band. However, for higher frequency bands, due to the high fade margins needed to achieve high availability and performance for SDH systems, it is not practical to transmit the STM-1 signal using such standard transponder bandwidths