Patent ID: 6047192
Filing Date: 2000-04-04
Classification: G01S

Abstract:
An apparatus for locating a standard, mobile-communications, radio transmitter in a cellularized communications system, comprising:at least first and second sensor stations, each sensor station having an antenna and associated signal conditioning means for receiving a signal from the mobile radio transmitter and a timing mechanism to time-tag an identified, representative instant of the received signal to produce time-tagged received signal data;at least first and second signal replica units at the first and second sensor stations, respectively, each signal replica unit providing replicated signal data,at least first and second signal correlation and measurement extraction processing units at the first and second sensor stations, respectively, each correlation and measurement extraction processing unit performing matched-replica correlation processing with the time-tagged received signal data and the replicated signal data to produce location-related signal parameters;a communications system for communicating the location-related signal parameters from the first and second sensor stations to a central site;means for estimating the position of the mobile transmitter from the location-related signal parameters produced at only the first and second sensor stations; andan output for indicating the estimated position of the mobile transmitter,whereinthe signal replica unit at at least the first sensor station comprises a reduction mechanism to reduce the time-tagged received signal data,the communications system communicates the reduced time-tagged received signal data between at least the first sensor station and the second sensor station, andthe signal replica unit at at least the second sensor station comprises a reconstruction mechanism to reconstruct the reduced time-tagged received signal data and to use the reconstructed time-tagged received data as the replicated signal data.