Granted Patent
Utility
US 6,226,380 · App. 09/026,434
Method of distinguishing between echo path change and double talk conditions in an echo canceller
Inventor:
Heping Ding
Patented Case
View Patent ↗
Granted: May 1, 2001
Filed: Feb 19, 1998
Inventor
Heping Ding
Assignee (at issue)
Nortel Networks Limited
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.