Passive ranging system

摘要

A passive ranging system for determining the range of a target radar by utilizing the scan characteristics of the target radar. Receivers are placed on each of two aircraft flying in a specified formation. One aircraft relays detected pulse amplitude envelopes to the other aircraft. The second aircraft measures time delay between impacts of the main beam of the target radar on the two aircraft and a computer determines range according to equation R=D/K DELTA t where DELTA t is the measured time difference, D is the distance between aircraft and K is a constant depending on the type of target radar.