Digital Filtering Basics **new** 2003/11/17 14:39:37.986 US/Central 2003/11/17 14:40:42.823 US/Central Deania M. Fernandez deaniafe@rice.edu Deania M. Fernandez deaniafe@rice.edu digital FIR finite impulse response filtering filter In this module, the basics of digital filtering is discussed.

You should be familiar with analog filters, which takes an analog input signal and output analog signal. Digital filters, with the sampling device and digital-to-analog converter, can do the same job as analog filters. Analog filters are specified by its impulse response ht and the output signal yt for input signal xt is given by the convolution integral y t t 0 t x t u h u Similarly, digital filters are specified by its impulse hn and the output sequence yn for the input sequence (samples of input analog signal) xn by the discrete convolution y t k 0 N 0 h k x n k The filter design problem is to design the impulse response h n so that the digital filter, together with the sample and D/A converter, performs the same processing as the analog filters. There are many possible ways to pick h n to implement filtering.