03967264 is referenced by 135 patents and cites 4 patents.

A distribution network power line communication system which is divided into addressable communication zones defined by repeaters located at the distribution transformers of the distribution network. Each repeater, when uniquely addressed by an interrogation signal from an interrogating source, strips its address from the interrogation signal and sends the resulting modified interrogation signal to its associated remote communication terminals, by-passing the associated distribution transformer. A timely, error-free response signal from a remote communication terminal is modified by a repeater to include the repeater address, and the modified response signal is sent back to the interrogating source. The binary base band interrogation and response signal information is preferably pulse width modulated to provide a self clocking format, and this self clocking signal is passed through two stages of frequency modulation to provide a signal which makes the receivers thereof substantially immune from drift.

Title
Distribution network power line communication system including addressable interrogation and response repeater
Application Number
5/546069
Publication Number
3967264
Application Date
January 31, 1975
Publication Date
June 29, 1976
Inventor
James P McGivern
Pittsburgh
PA, US
Louis G Ottobre
Murrysville
PA, US
Ian A Whyte
Pittsburgh
PA, US
Agent
D R Lackey
Assignee
Westinghouse Electric Corporation
PA, US
IPC
H04M 11/04
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