3702460 is referenced by 142 patents and cites 12 patents.

An electric power utility communication system is disclosed comprising a plurality of geographically distributed group control units and groups of terminal processor units, with each such terminal processor unit within a group coupled to a respective group control unit through the neutral conductor of the power utility distribution lines. Availability of the neutral as a communications link is achieved by inserting a parallel resonant circuit between the neutral and ground at each ground point in the system. Alternately, the signal generating and/or receiving equipment may be connected between the conventionally grounded neutral and deep earth ground, to develop the communications signal across the earth impedance. Communications information is transmitted over the neutral by coded high frequency signals to the terminal processor units which have electronic logic capacity to accept and perform command functions, interrogate meters, and transmit information back over the neutral to their respective group control units. Overall control is achieved by a central computer controller coupled to each group control unit by conventional transmission means, and which generates and receives coded signals through the group control units.

Communications system for electric power utility
Application Number
Publication Number
Application Date
November 30, 1971
Publication Date
November 7, 1972
Blose John B
H04q 11/00
H04b 13/02
H04Q 09/14
H04B 03/54
H02J 13/00
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