Design of Numerical Filters with Applications to Missile Data Processing

Abstract. A discussion of the process of numerical (digital) filtering is presented together with formulae for a particularly simple but effective design. The error is discussed in terms of the quantity ~(~, N) with k the normalized frequency and N the number of filter weights. Later empirieM design curves with e as a parameter are given. In addition, the effect of allowing slope discontinuities in the filter transfer function is noted. Next, the problem of trend type errors and their elimination by the inclusion of additional constraints on the filter weights is included. Designs for high-pass, band-pass and quadrature filters, with a comparison of two band-pass design approaches, are given. Specific applications are given to illustrate the effect of the filtering process as well as the various ways filters can be used in processing digital data.