Comparison of PSK and DPSK modulation in a coded OFDM system

Orthogonal frequency division multiplexing (OFDM) is often proposed for high data rate transmission over frequency-selective channels in order to simplify equalisation. In this paper 4- and 8-PSK and DPSK with coherent and non-coherent demodulation are considered for performance comparison. A channel estimation and equalisation is necessary for coherent demodulation whereas this effort is not required in the case of non-coherent detection. The performance comparison is made for convolutionally coded OFDM systems.