z-transform analysis of nonuniformly sampled digital filters

The paper presents a z transform analysis of digital filters operated with nonuniform sample periods. The analysis is applicable to filters using a mean-square definition of transfer function, e. g. moving-target-indicator filters, and also to conventional digital filters. The evaluation of the frequency response of such filters using the analytic results of the paper leads to considerable savings in computation time over direct simulation methods. Nonuniform sampling of conventional digital filters is shown to result in a reduction of the effective Nyquist frequency, although, within this limited frequency range, additional control of the frequency response is possible for certain filters. A pole-zero diagram may be drawn for a nonuniformly sampled filter, and allows comparisons to be made with the corresponding uniformly sampled case.