Optimum Design of FIR Pulse Shaping Filter with Reduced Coefficients

Abstract

Pulse shaping filters have been designed and implemented by using Raised cosine filter, Nyquist filter and optimized half band filters for software defined radio (SDR) based wireless applications. In signal processing, a finite impulse response (FIR) filter is a filter whose impulse response (or response to any finite length input) is of finite duration, because it settles to zero in finite time. This is in contrast to infinite impulse response (IIR) filters, which have internal feedback and may continue to respond indefinitely (usually decaying). Filter design is the process of designing a filter ,often a linear shift-invariant filter that satisfies a set of requirements, some of which are contradictory. The purpose is to find a realization of the filter that meets each of the requirements to a sufficient degree to make it useful. The filter design process can be described as an optimization problem where each requirement contributes with a term to an error function which should be minimized. Certain parts of the design process can be automated, but normally an experienced electrical engineer is needed to get a good result. The high order demand imposes more hardware requirements, arithmetic operations, area usage, and power consumption when designing and fabricating the filter. Therefore, minimizing or reducing these parameters, is a major goal or target in digital filter design task. In this paper we proposed an Optimum Design of FIR Pulse Shaping Filter with Reduced Coefficients. The performance of the designed filter has been studied in terms of its impulse response as well as magnitude response. For this we take the length parameter as 73 and 85. The results show that the BER performance of the optimized designs is almost identical to the Raised cosine filter with significant reduction in hardware requirements. The result of matlab simulation shows that our approach provides a significant reduction in the number of coefficients without much degradation in its performance.