Phase coded nonlinear asymmetric chirp modulation

Abstract

In this paper we present a class of signals referred to as Multi-mode Asymmetric Continuous Phase Chirp Modulation (MA-CPCM). In these signals modulation parameters are time-varying and function of present and past data bits entering the modulator. The proposed class of signals offers additional degrees of freedom and flexibility to the designer. It is shown that constructions of MA-CPCM exit with superior distance properties compared to conventional CPCM. An addition of 1-bit memory in MA-CPCM results in a coding gain of nearly 2 dB relative to CPCM. The detection of MA-CPCM using multiplesymbol observation window is addressed and the optimum minimumerror-probability receiver is derived. It is shown that this optimum receiver offers nearly 1 dB gain over optimum CPCM receivers. MA-CPCM finds possible applications in cordless systems, Wireless Local Area Networks, air-to-ground communication via satellites, and, in general, in hostile EM environments.