Frequency-Selective Limiter and Its Application in a Filter Bank Receiver

摘要

The operating theory of parametric FSL's (frequency-selective limiters) and the measured results of a yttrium iron garnet (YIG) FSL under different signal environments are reported. Emphasis is given to application YIG FSL's as level normalizers in a filter bank receiver. YIG FSL operation is discussed via a basic analytical model. In this study, transient response to pulsed RF signals, frequency modulated signals, small signal suppression and intermodulation product phenomena when two signals are simultaneously received, are also reported. Experimental results obtained agree with the analytical model. Extensive data are provided to facilitate design of YIG FSL's in filter bank receivers. Specific applications for YIG FSL's are present: YIG FSL as a level normalizer, cascading YIG FSL's to obtain large limiting range, threshold level detection influenced by small signal suppression, and use of a YIG FSL to offset amplitude reduction of bandpass filters caused by a sweep signal. A filter bank receiver comprising YIG FSL's is presently under construction. (Modified author abstract)