On diversity reception of narrow-band 16 STAR-QAM in fast Rician fading

An expression for the bit-error rate (BER) of 16 STAR-quadrature amplitude modulation (QAM) with differential encoding and detection in a Rician fading channel with diversity reception is obtained. Two types of intermediate frequency (IF) filters are considered in the analysis: the intersymbol interference (ISI)-free matched and nonISI-free Gaussian filters. BER curves for various ratios of the line-of-sight (LOS) power to the multipath power, Doppler spread frequencies, and orders of diversity are presented. It is shown that 16 STAR-QAM outperforms 16 DPSK under the same power-limited condition. For the Gaussian receive filter, a filter bandwidth of about 1.2 times the symbol rate is found to lead to a minimum error probability prior to the appearance of error-rate floors.