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In most of the applications, analog signals are produced in response to some physical phenomenon or activity. But it is quite difficult to process that analog signal; here comes the need to convert an analog signal to a digital signal. For this purpose specific digital signal processors (DSP’s) are developed. TMS 320C6713 is one of such type of processors that can be used to process or handle the signals in a variety of ways. In the current report, basically the architecture of this processor is studied. Along with the processor architecture, the hardware portion DSK (Digital Starter Kit) and the software portion CCS (Code Composer Studio) is also studied. Digital filters are very commonly found in everyday life and include a variety of applications. Mainly they are used for two major purposes: signal separation and signal restoration. Signal separation is needed when a signal has been contaminated with interference, noise, or other signals. Signal restoration is used when a signal has been distorted in some way. So, various programs have been analyzed in this work to implement efficiently those FIR filter structures on TMS 320C6713 DSK. Characteristics of FIR filters are studied in frequency domain.

Filters are used in electronic circuits to remove the unwanted frequency components from desired signals. A digital filter basically provide high attenuation to the unwanted ones and offer very low or ideally zero attenuation to desired signal components when it’s impulse response is adjusted as per requirement. For ideal filters, the length of such an impulse response is infinite and also the filter will be non-causal and unrealizable. So, we need to truncate this infinite impulse response to make it finite. For this truncation, we use window functions. Using window functions, we obtain a finite impulse response or simply FIR filter. The shape of a window in time domain decides the characteristics of resultant filter in frequency domain. Several window functions are available in literature. For the present work we have choosen the three parameter Cosh window for truncation of infinite impulse response. It is also called as modified Cosh window because it has been obtained by inserting a third parameter in the basic 2-parameter Cosh window function. The main goal of this work is to study this modified Cosh window and design a digital low pass FIR filter using the same in MATLAB. First of all the properties of window function are described and frequeny domain responses of window function is obtained. Then FIR filter is analyzed using window design method and it’s characteristics have also been studied in frequency domain.