05592180 is referenced by 133 patents and cites 43 patents.

A special mobile radio mobile, vehicle or personal location system is described where the system operates to locate any one of a the transmitters in an SMR system. The present invention operates by identifying the received signals, removing the modulation information to reconstruct a demodulated carrier and analyzing the carrier signals for multipath distortion. The multipath disruptions are removed to calculate the true incident angle of the transmitted signal at a base station. A plurality of base stations are used to simultaneously calculate the incident angle of the transmitted SMR signal and a central location calculates the most probable location of the transmitter based upon triangulation. The incident angle of the transmitted SMR signal at each base station is performed by calculating the phase differences of the incoming voice signal with phase ambiguity minimized by using a plurality of dipole antennas spaced at an irregular distance to eliminate phase ambiguity error.

Title
Direction finding and mobile location system for trunked mobile radio systems
Application Number
932610
Publication Number
5592180
Application Date
October 26, 1994
Publication Date
January 7, 1997
Inventor
Shimon Peleg
Hod Hasharon
IL
Yehouda Meiman
Rishon Letzian
IL
Haim Harel
Herzelia
IL
Hanoch Yokev
Ramat-Gan
IL
Agent
Schwegman Lundberg Woessner & Kluth P A
Assignee
Nexus1994
GB
IPC
G01S 3/02
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