Adaptive Demodulation in Differentially Coherent Phase Systems: Design and Performance Analysis

Adaptive Demodulation (ADM) is a newly proposed rate-adaptive system which operates without requiring Channel State Information (CSI) at the transmitter (unlike adaptive modulation) by using adaptive decision region boundaries at the receiver and encoding the data with a rateless code. This paper addresses the design and performance of an ADM scheme for two common differentially coherent schemes: M-DPSK (M-ary Differential Phase Shift Keying) and M-DAPSK (M-ary Differential Amplitude and Phase Shift Keying) operating over AWGN and Rayleigh fading channels. The optimal method for determining the most reliable bits for a given differential detection scheme is presented. In addition, simple (near-optimal) implementations are provided for recovering the most reliable bits from a received pair of differentially encoded symbols for systems using 16-DPSK and 16DAPSK. The new receivers offer the advantages of a rate-adaptive system, without requiring CSI at the transmitter and a coherent phas...

• Type: Journal
• Year: 2010
• Where: CORR
• Authors: J. David Brown, Jamshid Abouei, Konstantinos N. Plataniotis, Subbarayan Pasupathy
• Keywords: Adaptive, CORR 2010, Education, Phase Shift, Reliable Bits