A coded quaternary CPM scheme for data exchange over satellite-vehicle/personal communication applications

Abstract

A coded modulation scheme named "coded QTFM" is proposed for the purpose of satellite-vehicle/personal communication facilities. QTFM is a 4-level continuous phase modulation (CPM) scheme with bandlimiting baseband LPF. Coded QTFM improves the error performance of QTFM tremendously with high coding efficiency (/spl sim/0.9). Block encoding and the maximum likelihood sequence estimation is adopted in the proposed system. A simple (10,9) code improves the bit error rate to almost the same value attained by bandlimited QDPSK with raised cosine filter of roll-off factor /spl alpha/=1.<>