Patent ID: 8830122
Filing Date: 2014-09-09
Classification: G01S

Abstract:
1. A system for determining a location of a radio frequency (RF) emitter transmitting an RF signal, the system comprising: a long baseline interferometer (LBI) including a first antenna and a second antenna positioned on a vehicle to receive the RF signal transmitted by the RF emitter; a short baseline interferometer (SBI) including a third antenna and a fourth antenna positioned on the vehicle to receive the RF signal transmitted by the RF emitter; and a processor positioned on the vehicle configured to: a) determine a first phase rate of change (PROC) of the RF signal received by the LBI over a short time interval to produce a short time interval range estimate of the RF emitter, b) determine a second PROC of the RF signal received by the LBI over a long time interval which is greater than the short time interval, to produce a plurality of long time interval range estimates of the RF emitter, c) determine an angle of arrival (AOA) of the RF signal received by the SBI, d) select one of the plurality of long time interval range estimates based on the short time interval range estimate, and e) determine the location of the RF emitter based on the selected long time interval range estimate and the determined AOA in step c.