The Design of a Square-Root-Raised-Cosine FIR Filter by a Recursive Method

Abstract

Using a pair of matched square-root-raised-cosine (SRRC) filters in the transmitter and. the receiver in a bandlimited digital communication system can theoretically achieve zero inter-symbol interference (ISI). In reality, such a pair of SRRC filters does not exist. The ISI can be only reduced to some level when both SRRC filters are approximately implemented. We propose a recursive method to design the SRRC FIR filters. The ISI achieved by using the resulting matched SRRC-filter pair can be very low while the frequency domain specification of the SRRC filter is still maintained. The impact of clock jitter on the ISI of systems using different SRRC filters are simulated and compared.