05196846 is referenced by 98 patents and cites 20 patents.

A system for exchanging information by means of transmitted RF signals between a fixed location interrogator and a vehicle transponder moving in the vicinity of the interrogator. The transponder responds to a first trigger signal from the interrogator by transmitting to the interrogator a first data message derived from data stored in a transponder memory. The interrogator then remotely reprograms the transponder memory and generates a second trigger pulse. The transponder responds to the second trigger pulse by transmitting the reprogrammed data it then stores and the interrogator analyzes the last mentioned transmission to determine if the transponder properly received and responded to the reprogramming.

Title
Moving vehicle identification system
Application Number
234570
Publication Number
5196846
Application Date
June 18, 1990
Publication Date
March 23, 1993
Inventor
Donald P Gillis
11448 71st Avenue, Edmonton
CA
Michael L Hryciuk
11719-28 Avenue, Edmonton
CA
Conrad M B Walker
Rural Route #5, Site 11, Edmonton
CA
William K Brockelsby
11025 82 Avenue #1006, Edmonton
CA
Agent
Fitch Even Tabin & Flannery
IPC
G08G 1/01
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