Digital signal processing. 1. Digital filters and the DFT

The wide availability of inexpensive and relatively fast digital signal processing chips has given rise to a great expansion in the application of these devices in many areas, particularly consumer electronics. The ease with which digital processing operations can now be performed has allowed the realisation of highly sophisticated signal processing algorithms. The paper introduces the first of two main areas of digital signal processing, namely digital filtering and Fourier transformation. An overview is presented of both finite impulse response and infinite impulse response digital filter types. These designs are later extended to cover the concept of an adaptive filter, which automatically trains or adapts its characteristics or frequency response to compensate for signal distortions or interference. Finally, the discrete Fourier transform is introduced for measuring the frequency spectrum of a signal