04449114 is referenced by 124 patents and cites 5 patents.

A system for detecting the location and identification of a number of vehicles at multiple points on a given track against a time gauge which includes an on-board transmitter on each vehicle of a unique identifying frequency, spaced receiving circuit elements along the track at multiple points connected to individual transmitters to receive and modify the identifying signal and transmit the signal to a programmed computer for translating the multiple signals of the different unique identifying frequencies into signals ascertainable on a portable hand apparatus selectively to indicate the speed of any selected vehicles as in a race, and to keep track of position standings and lap times.

Title
System for identifying and displaying data transmitted by way of unique identifying frequencies from multiple vehicles
Application Number
134664
Publication Number
4449114
Application Date
March 26, 1982
Publication Date
May 15, 1984
Inventor
Rollin W Ache
Phoenixville
PA, US
Daniel L Gregg
San Francisco
CA, US
Anthony C Fascenda
Pacifica
CA, US
Agent
Flehr Hohbach Test Albritton & Herbert
Assignee
Dataspeed
CA, US
IPC
G08B 1/12
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