New SRRC receiver filter design with reduced number of filter taps for wireless communication systems

Abstract

In wireless communication systems, it is well known that inter-symbol interference (ISI) can be avoided by using a pair of matched square-root-raised-cosine (SRRC) filters in the transmitter and receiver. In an effort to find methods which minimise the number of filter taps in the matched filter, numerous studies have been done. However, in practise, when the communication specification is fixed by the standard, it is not possible to change the coefficients of the transmit filter. In this study, the authors propose a new SRRC filter design with the reduced number of filter taps for a receiver of a wireless communication system. The proposed design utilises a recursive steepest-descent algorithm when the filter coefficients of the transmitter are fixed. That is, relaxing the ISI criterion while maintaining the stopband attenuation, the proposed receiver filter has fewer filter taps than that in the conventional case without undergoing bit error rate performance degradation. The proposed receiver filter design with the reduced number of filter taps reduces the computational complexity and the detection delay in the receiver.