ANALYTICAL AND EXPERIMENTAL CHARACTERIZATION OF SOQPSK AND MULTI-H CPM IN A MULTIPATH CHANNEL

Abstract

Shaped Offset QPSK (SOQPSK) has been shown to be nearly identical in performance to Feher-patented FQPSK, which is the Advanced Range Telemetry (ATRM) program's Tier I waveform. Multi-h CPM has been selected as the ARTM Tier II waveform, because it offers 50% better spectral efficiency than the Tier I waveform. Both the Tier I and Tier II waveforms must operate in a multipath channel in order to meet the range community's telemetry requirements. This paper presents an analytical and experimental characterization of SOQPSK and Multi-h CPM in the presence of multipath. Quantitative results are presented which demonstrate the relative robustness of the ARTM Tier I and Tier II waveforms, in channels representative of a typical range environment.