Accession Number : ADD000416

Title :   Passive Ranging by Time Difference Multi-Path.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON D C

Personal Author(s) : Kang,George S ; Berry,Allan E

Report Date : 28 Jan 1975

Pagination or Media Count : 8

Abstract : The patent relates to range from an observer to an electromagnetic emitter determined by the geometry of ellipse in which the observer is at one focus, the emitter is at the other focus, and a reflector lies on the locus. The time difference of arrival of the direct signal from the emitter and the reflected signal is measured and used to compute the distance from the vortex behind the observer to the observer. Also the rate of change of the successive time differences of arrival is determined and this value together with the observer's speed and the emitter bearing is used to compute the reflector's position with respect to the observer. The reflector's position and the vortex to observer's position is used to compute the eccentricity of the ellipse which is in turn used together with time difference of arrival to compute the range.

Descriptors :   *Range finding, *Patents, Passive systems, Time, Electromagnetic wave reflections

Subject Categories : Active & Passive Radar Detection & Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE