Granted Patent
Utility
US 4,636,586 · App. 06/778,314
Speakerphone with adaptive cancellation of room echoes
Inventor:
Leonard N. Schiff
Patented Case
View Patent ↗
Granted: Jan 13, 1987
Filed: Sep 20, 1985
Inventor
Leonard N. Schiff
Assignee (at issue)
RCA Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.