04652703 is referenced by 80 patents and cites 13 patents.

A digital voice communication apparatus having improved echo suppression includes a transmission gain detection circuit for detecting a near talker signal and a receiver gain detection circuit for detecting a far talker signal. An echo detecting circuit detects which of the near talker and far talker signals has a lesser value and suppresses the gain of the one detected to have the lesser value. A far talker suppressing circuit detects whether the most recent peak gain in this near talker signal is greater than a threshold and is greater than the gain of the far talker signal. If this condition exists the far talker signal is suppressed. A near talker signal suppressing circuit detects whether the most recent gain of the far talker signal is greater than a threshold and is greater than the gain of the near talker signal. If so, the gain of the near talker signal is suppressed.

Title
Digital voice transmission having improved echo suppression
Application Number
6/471137
Publication Number
4652703
Application Date
March 1, 1983
Publication Date
March 24, 1987
Inventor
Jay P Jayapalan
Hollywood
FL, US
Jack E Stephenson
Davie
FL, US
William J Miller
Miami
FL, US
Chun C Lu
Miami
FL, US
Agent
William A Newton
Jerry A Miller
Assignee
Racal Data Communications
FL, US
IPC
H04B 3/20
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