Granted Patent
Utility
US 6,697,486 · App. 09/533,968
Echo canceler and operating method
Inventor:
Masashi Takada
Patented Case
View Patent ↗
Granted: Feb 24, 2004
Filed: Mar 23, 2000
Inventor
Masashi Takada
Assignee (at issue)
OKI ELECTRIC INDUSTRY CO., LTD.
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.