Granted Patent
Utility
US 4,939,748 · App. 07/083,696
Unobtrusive signature for modulated signals
Inventors:
William L. Betts, Kenneth Matinez
Patented Case
View Patent ↗
Granted: Jul 3, 1990
Filed: Aug 7, 1987
Inventors
William L. Betts
Kenneth Matinez
Assignee (at issue)
PARADYNE CORPORATION
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.