04891650 is referenced by 432 patents and cites 29 patents.

A system for determining a location of a selected vehicle from which an alarm signal is generated which includes a fixed array of cellular sites each site having a wireless signal detecting and generating units each of which is capable of receiving an input alarm signal having a signal strength which is a function of the distance between the position of the vehicle generating the alarm signal and the position of each of the wireless signal detecting units. Each unit also is capable of transmitting an output signal which is a function of the strength of the input alarm signal. The system also includes a main wireless signal detecting apparatus for receiving an output signal from each of the wireless signal detecting and generating units and a control monitoring unit which is coupled to the main wireless signal detecting apparatus, for receiving output signals there from, each of the output signals being a function of the strength of the received input alarm signal, for determining the approximate location of the selected vehicle from which the alarm signal is generated.

Title
Vehicle location system
Application Number
7/194479
Publication Number
4891650
Application Date
May 16, 1988
Publication Date
January 2, 1990
Inventor
Eliezer A Sheffer
Plainview
NY, US
Agent
Rosen Dainow & Jacobs
Assignee
TrackMobile
CA, US
IPC
G01S 3/02
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