초록 ▼

A method for determining the geolocation--i.e., the latitude, longitude, and altitude--of a stationary emitter emitting an RF signal. The method employs at least one moving observer to measure electrical phase change of the emitter over two or more successive dwell intervals, and at least two observ

A method for determining the geolocation--i.e., the latitude, longitude, and altitude--of a stationary emitter emitting an RF signal. The method employs at least one moving observer to measure electrical phase change of the emitter over two or more successive dwell intervals, and at least two observers, moving or stationary and of known position, to determine the pulse time of arrival of the emitter signal. The phase change measurements are taken using a long baseline interferometer (LBI), and the pulse time of arrival measurements are calculated using short baseline interferometers (SBI). Circles of position are generated from bearing change measurements ascertained from the LBI phase change measurements, and hyperbolic lines of position are generated based on the SBI measurements. The position of the emitter is then determined from the intersection of the circles and lines of position.

대표청구항 ▼

[ What is claimed is:] [1.] A method for determining the geolocation of a stationary emitter, the method comprising the steps of:measuring using a long baseline interferometer (LBI) the ambiguous electrical phase change of the emitter signal corresponding to the change in signal angle of arrival (AO

[ What is claimed is:] [1.] A method for determining the geolocation of a stationary emitter, the method comprising the steps of:measuring using a long baseline interferometer (LBI) the ambiguous electrical phase change of the emitter signal corresponding to the change in signal angle of arrival (AOA) due to observer movement with respect to the emitter;resolving the ambiguous electrical phase change to determine the electrical phase measurement from the ambiguous set that is uniquely associated with the AOA or bearing change;utilizing the electrical phase measurement to calculate the bearing change of the observer;creating circles of position (COPs) along which the emitter must lie based on the bearing change;calculating the time difference of arrival (TDOA) of the emitter RF signal received by at least two observers of known position;generating a hyperbola along which the emitter must lie based on the TDOA calculations from the at least two observers; anddetermining the intersection of the COPs and hyperbola to arrive at a distinct point of location.