Granted Patent
Utility
US 5,638,439 · App. 08/616,962
Adaptive filter and echo canceller
Inventors:
Shinichi Kawada, Kenichi Shindate
Patented Case
View Patent ↗
Granted: Jun 10, 1997
Filed: Mar 15, 1996
Inventors
Shinichi Kawada
Kenichi Shindate
Assignee (at issue)
OKI ELECTRIC INDUSTRY CO., LTD.
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.