Custom Filters

Most filters have one of the four standard frequency responses: low-pass, high-pass, band-pass
or band-reject. This chapter presents a general method of designing digital filters with an
arbitrary frequency response, tailored to the needs of your particular application. DSP excels
in this area, solving problems that are far above the capabilities of analog electronics. Two
important uses of custom filters are discussed in this chapter: deconvolution, a way of restoring
signals that have undergone an unwanted convolution, and optimal filtering, the problem of
separating signals with overlapping frequency spectra. This is DSP at its best.
CHAPTER
Custom Filters
17

Most filters have one of the four standard frequency responses: low-pass, high-pass, band-pass
or band-reject. This chapter presents a general method of designing digital filters with an
arbitrary frequency response, tailored to the needs of your particular application. DSP excels
in this area, solving problems that are far above the capabilities of analog electronics. Two
important uses of custom filters are discussed in this chapter: deconvolution, a way of restoring
signals that have undergone an unwanted convolution, and optimal filtering , the problem of
separating signals with overlapping frequency spectra. This is DSP at its best.




Arbitrary Frequency Response
The approach used to derive