Granted Patent
Utility
US 4,677,423 · App. 06/816,578
ADPCM coder-decoder including partial band energy transition detection
Inventors:
Nevio Benvenuto, Guido Bertocci
Patented Case
View Patent ↗
Granted: Jun 30, 1987
Filed: Jan 6, 1986
Inventors
Nevio Benvenuto
Guido Bertocci
Assignee (at issue)
American Telephone and Telegraph Company, AT&T Bell Laboratories
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.