Performance of sinusoidally-distributed dithering for signed-error constant modulus algorithm

Abstract

The complexity of the ubiquitous constant modulus algorithm (CMA) can be reduced by applying a sign operation to the CMA error function, while a sign operator generally can be seen as a 1-bit (two-level) mid-riser quantization. However, in order to preserve the information lost as a result of quantization processes, dithering is commonly used. In this paper, we evaluate the performance of dithered signed-error CMA utilizing a dithering signal that has sinusoidal probability density function. The algorithm has also been applied for equalization in wireless communication channel, which is distorted by multi-path propagation. Simulation results show that dithering using sinusoidal distribution outperforms the dithering using uniform distribution in terms of convergence speed.