BAND-LIMITED DS-CDMA USING EXPONENTIALLY WEIGHTED DESPREADING SEQUENCE

The signal-to-interference ratio (SIR) performance of a bandlimited DS -CDMA system using an exponentially-weighted despreading sequence (EWD S) in the receiver [1] is addressed. It is shown that tuning a paramet er of the EWDS helps to flatten the in-band spectrum of the received c oloured signal, leading to a better performance when the transmission bandwidth is limited. With the constraint of the system transmission b andwidth equal to and twice the chip rate, numerical results show that the SIR of the proposed system can be increased up to 28 and 94%, res pectively, when compared with a conventional receiver using a rectangu lar despreading sequence.