Granted Patent
Utility
US 5,694,466 · App. 08/588,407
DTMF detector system and method which performs improved twist computation and thresholding
Inventors:
Zheng Xie, John G. Bartkowiak
Patented Case
View Patent ↗
Granted: Dec 2, 1997
Filed: Jan 18, 1996
Inventors
Zheng Xie
John G. Bartkowiak
Assignee (at issue)
Advanced Micro Devices, 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.