04135156 is referenced by 158 patents and cites 5 patents.

A satellite relay communications system includes a ground relay station arranged so that each message from one subscriber to another is relayed by the satellite relay to the ground relay, processed by the ground relay and then transmitted to the second subscriber by way of the satellite relay. Processing at the ground relay station includes a switching function in which the carrier frequency of each message is changed from the frequency used for transmitting by the subscriber sending each message to the frequency used for reception by the subscriber to whom the message is addressed. This permits each subscriber to use a single transmitting frequency and a minimum number of receiving frequencies.

Title
Satellite communications system incorporating ground relay station through which messages between terminal stations are routed
Application Number
5/481015
Publication Number
4135156
Application Date
June 20, 1974
Publication Date
January 16, 1979
Inventor
Alfred J Cann
Wilton
NH, US
Martin R Richmond
Lexington
MA, US
Royden C Sanders Jr
Wilton
NH, US
Agent
Joseph E Funk
Louis Etlinger
Assignee
Sanders Associates
NH, US
IPC
H04B 7/20
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