Performance Analysis of Window Technique Based Band Reject FIR Filter

The most important part of a Digital Signal Processing or DSP is a filter which passes the desired frequency components and rejects the unwanted signals as noise. So Digital filter play an important role in DSP based communication system. Digital filter has many advantages over the analog filter. FIR filter gives linear and stable performance as compare to IIR filter. In this paper Band reject filter is designed and analyzed using different window techniques. Blackman, Bartlett and Hamming windows are used for design simulation using Matlab. The performance of all the designs has been compared in terms of pass band ripples and roll off sharpness. The different filter orders of 16 and 36 is also used for design. It can be observed from the simulated results that Blackman window gives better roll off sharpness and Hamming window gives low pass band ripples. The result also shows that the performance of all the design is improved with increased filter order.