Both channel sounding and channel coding are well-known techniques for improving bit error rate (BER) performance of data transmission over a narrowband mobile radio channel. The two techniques share a common ground with regard to the fact that both of them use redundancy signals, (reference signals for channel sounding and parity check bits for channel coding) to achieve the improved performance. A comparison of theoretical phase-shift keying, (PSK) performance in terms of BER is made between the reference-based coherent binary phase shift keying detection and the BCH coded differential detection under different fading conditions. Comparisons are also made between reference-based coherent detection and BCH coded decision-feedback differential phase shift keying (DPSK)