This chapter presents the important features of 66 predesigned low-pass filters. These features are presented in a data sheet format, which we believe allows easy filter cross-referencing and assessment. In addition to the frequency and impulse response functions, a table of pertinent performance attributes is provided for each filter. These capture the characteristics of the predesigned digital filter in its entirety. Apart from the visual representation of the filters and their tabulated performance data, the filter coefficients are listed in electronic format and appended to this book.
There are aspects of the characteristics of the Gaussian-windowed FIR filter family that are of general interest. These characteristics show trends that allow the user to predict the attributes of other members of the filter family if required.
In many filtering applications the ?3dB frequency F ?3dB has become a recognizable parameter for defining the cut-off frequency of low-pass filters. In digital filtering though, it is easier to define the cut-off frequency F c, as the frequency at which the magnitude attains an absolute value of 0.5, since this is guaranteed by design. The consequence of using the F ?3dB measure is that it varies with filter length since the sharpness of the transition width is a function of the filter order. Additionally, as the filter order increases, the transition width decreases, and F ?3dB approaches F c asymptotically. Because of this, there is a...
TABLE OF CONTENTS 
