Multinotch logic-product polarisation suppression filters: a typical design example and its performance in a rain clutter environment

Polarisation filtering is applied in radar systems to improve target detection in adverse environments. Fluctuations of the polarisation states of unwanted incident signals dictate the need for filters that suppress such signals in the polarisation domain and cover a controllable area of polarisation space. This has led to the concept of the multinotch logic-product (MLP)polarisation filter which attempts to meet the above need. The paper describes the parameters that affect the general characteristics of the MLP filter, gives a typical design example and uses a representative set of experimentally derived rain clutter data to evaluate the performance of this MLP filter.