04031513 is referenced by 63 patents and cites 3 patents.

An improved remote meter reading system is disclosed comprising apparatus for transmitting UHF AM interrogating signals from an interrogating mobile or central station to a remote transponder station, and apparatus for retransmitting UHF FM data signals from the energized transponder to the mobile or central interrogating station. The interrogating station further includes apparatus for validating that the UHF FM data signals received are in fact the UHF FM data signals actually sent by the remote transponder selected by the interrogating or central station.

Title
RF data exchange system
Application Number
5/522019
Publication Number
4031513
Application Date
November 8, 1974
Publication Date
June 21, 1977
Inventor
Walter Simciak
Longwood
FL, US
Agent
Johnson Dienner Emrich & Wagner
Assignee
Northern Illinois Gas Company
IL, US
IPC
H04Q 9/00
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