A 64 Channel Multiplexer with Frequency Discrimination Characteristics

This paper describes a new class of multiplexing filter structure that has both the properties of channelized filtering and channelized linear frequency discrimination. The channelized filter-discriminator is intended for use as part of a microwave receiving system possessing a high probability of intercept for incoming signals. The selective properties of the band pass filters provide an interference-reduction capability while the discriminator property provides for instantaneous frequency measurement. The paper describes a design procedure for achieving a very high degree of discriminator linearity in association with a reasonable selectivity comparable to a maximally flat filter. The theoretical design data are provided in a normalized table generated by computer optimization. The hardware realization of a 64 channel multiplexer-discriminator is described. Measured data is presented that agrees very closely with the theoretical predictions.