Design of Chebyshev's IIR filter

In this experiment we designed a digital Chebyshev filter from analog filter. We took the input specifications for the following parameters: passband and stopband attenuation, passband and stopband frequency and also the sampling frequency. And then displayed the results in the form of waveforms on Scilab. We designed both the lowpass and the highpass filter and compared the values of passband and stopband attenuation with the given input values.We observed that magnitude spectrum exhibits ripple in paasband and no monotonic in stopband. Also the Chebyshev's filter requires less hardware components for realisation. Chebyshev filters have the property that they minimise the error between the idealised and the actual filter characteristic over the range of filter.

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