A side-lobe suppression system for primary radar

An auxiliary omni-directional receiving aerial and a logarithmic receiving channel identical to the radar receiving channel are used. A refinement of the system provides a sharp cusp in the omni-directional polar diagram coincident with the main lobe of the radar aerial. Nonlinear processing of the signals in the radar and omni-directional channels gives complete suppression of side-lobe signals. The operation of the system in the presence of jamming is examined. Illustrations are given of the performance of the system under several conditions. It is especially effective in suppressing pulse interference from other radars.