LABORATORY INVESTIGATION INTO FQPSK OPERATIONAL CHARACTERSITICS

Abstract

Due to increasing data rates required for Flight Test telemetry on upcoming programs, and because of increasing competition for spectrum space, Boeing Integrated Defense Systems (IDS) Flight Test in Saint Louis is considering use of the Feher-patented Quadrature Phase Shift Keying (FQPSK) modulation scheme. To determine potential operational issues associated with FQPSK, Boeing IDS Flight Test initiated a laboratory investigation of FQPSK using commercially available equipment including a transmitter from Herley and a demodulator from RF Networks. This paper describes the results of this laboratory investigation, including spectrum occupancy, bit-error rate performance, demodulator acquisition performance, demodulator bit-rate tracking, demodulator pattern sensitivity, and other operational characteristics.