Abstract—In this paper, we study the modulation diversity in PSK scheme obtained by rotating the signal constellation and incorporating bit interleaving. We derive here the expressions for the average bit error rate (ABER) of rotated PSK modulation over frequency non-selective slowly fading Rayleigh and Ricean channels using moment generating function (MGF) based approach. Numerical results are obtained to compare the performance of conventional and rotated modulation schemes. We investigate the dependence of bit error rate on signal-to-noise ratio, fading parameters and the angle of rotation. The results show the improved performance of rotated scheme over conventional method in both the fading models. Also significant gain is noted for the case of strong LOS component. We also find and discuss the optimum rotation angle in rotated PSK scheme. The symmetrical nature of BER with rotation angle is observed.

Index Terms—Average bit error rate, bit interleaving, diversity, moment generating function, rayleigh fading channel,rotating signal constellation.

Both the authors are with the Mody Institute of Technology and Science(Deemed University), Lakshmangarh, Dist. Sikar, Rajasthan 332311, INDIA(e-mail: kapil_mbm@yahoo.com; pkghosh_ece@yahoo.co.in ).

Cite: Kapil Gupta and P. K. Ghosh, "Comparison of Bit Error Performance of Rotated PSK Scheme in Rayleigh and Ricean Fading Channels," International Journal of Computer and Electrical Engineering vol. 4, no. 1, pp. 37-41, 2012.