SBPSK: A Robust Bandwidth-Efficient Modulation for Hard-Limited Channels

A family of constant-envelope modulation formats is described in which good spectral containment is achieved through the use of controlled phase trajectories. The phase trajectory of shaped BPSK (SBPSK) in particular is such that it can be considered a PSK/FSK hybrid. For one member of this family, 50% SBPSK, extensive analytical results are presented, including sensitivities to filter bandwidths, timing jitter, phase jitter, and frequency error. In addition, performance in the presence of multiple adjacent channel interferers in a hard-limited satellite channel is analyzed and performance comparisons to conventional modulations are presented.