Granted Patent
Utility
US 6,055,310 · App. 08/992,581
Phase reversal tone detector using DSP
Inventors:
Naigang ZHANG, Quentin James Meek
Patented Case
View Patent ↗
Granted: Apr 25, 2000
Filed: Dec 17, 1997
Inventors
Naigang ZHANG
Quentin James Meek
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.