High fractionally spaced constant modulus blind equalization for high order-QAM signalling

Blind channel equalization has gained a wide-spread use in communications systems. This type of equalization doesn´t make use of any training sequence. The most commonly used blind adaptation algorithm is known as the constant modulus algorithm (CMA). The present paper presents the performances of fractionally spaced constant modulus equalization applied for 256-QAM and 1024-QAM modulated signals. Two ways of sampling the received data are investigated. The very known T/2FSE where the received signals are sampled at rate twice the baud rate and T/8FSE where the received signal is sampled at rates which are eight times the baud rate