Response of an Airborne-Short-Pulse Radar to Chaff

摘要

Radar backscatter from a chaff cloud is examined for the case in which the radar approaches the cloud from above and moves into and through the cloud. The chaff cloud is modelled as a collection of randomly oriented dipoles having a mean volume density that is a function of altitude but invariant in a horizontal plane. The statistics of the chaff echo power when the number of dipoles in the resolution volume is large are reviewed. The impulse response, which approximates the short-pulse radar response, and the radar return signal for a specific range resolution cell as a function of the position of the radar relative to the cloud are derived for several chaff cloud configurations and antenna patterns. Power spectral density functions for range-gated chaff-return signals and correlation functions for the signals following square-law detection are also derived. (Author)