04390990 is referenced by 7 patents and cites 8 patents.

By coincidentally injecting a predetermined level of direct current with the transmission of data on a transmission line, multiple signal transmissions on the line can be detected by the presence of a DC level greater than a predetermined level on the line. Once detected, tactics for avoiding multiple signal collision problems can be implemented.

Title
Method for multiple signal collision detection on a transmission line
Application Number
6/184855
Publication Number
4390990
Application Date
September 8, 1980
Publication Date
June 28, 1983
Inventor
Gerald L Ainsworth
Palo Alto
CA, US
Agent
Jeffery B Fromm
Edward Y Wong
Assignee
Hewlett Packard Company
CA, US
IPC
H04Q 9/00
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