Granted Patent
Utility
US 6,813,352 · App. 09/393,948
Quadrature filter augmentation of echo canceler basis functions
Inventor:
Donald L. Duttweiler
Patented Case
View Patent ↗
Granted: Nov 2, 2004
Filed: Sep 10, 1999
Inventor
Donald L. Duttweiler
Assignee (at issue)
LUCENT TECHNOLOGIES INC.
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.