Designing of Low Pass FIR filter for Processing of EMG Signal using Standard DSP Processor and Code Composer Studio

Digital signal processing (DSP) is the study of signals in a digital representation and the processing methods of these signals. A digital filter uses a digital processor to perform numerical calculations on sampled values of the signal. To achieve the desired filtering effect, Digital filters can achieve virtually any filtering effect that can be expressed as a mathematical function or algorithm. In this paper, we have filtered the EMG signals using FIR low pass filter and then amplified the filtered samples of EMG, using multiplication process through a program written in C language. For the purpose of designing the required FIR filter, first the coefficients of the filter are determined. MATLAB program has been used to determine the coefficients of the desired FIR filter by using the filter designing tool box of MATLAB. These coefficients reveal the characteristics of the desired filter. Although the frequency response characteristics possess by ideal filter may be desirable, they are not absolutely necessary in most practical applications if we relax these conditions, it is possible to realize causal filters that approximate ideal filters as closely as we desired. In this paper, we developed a digital FIR low pass filter having the cutoff frequency 120㎐ applicable on very small voltage signal like EMG. The faithful amplification is also been achieved through the digital amplification process. From our result studies, we observe that the proposed method is highly effective & efficient for EMG signal.