IP Library › Granted Patent US 4,947,425
Granted Patent Utility
US 4,947,425 · App. 07/428,081

Echo measurement arrangement

Inventors: Fredrick Grizmala, Barnet M. Schmidt, George Sultana
Patented Case View Patent ↗
Granted: Aug 7, 1990 Filed: Oct 27, 1989
Inventors
Fredrick Grizmala
Barnet M. Schmidt
George Sultana
Assignee (at issue)
AT&T Bell Laboratories

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Quick Facts
Patent No.
US 4,947,425
App. No.
07/428,081
Filed
1989-10-27
Granted
1990-08-07
Kind
A