Granted Patent
Utility
US 4,677,441 · App. 06/693,549
Two-way ranging system
Inventors:
Gunter Hofgen, Helmut Euler
Patented Case
View Patent ↗
Granted: Jun 30, 1987
Filed: Jan 22, 1985
Inventors
Gunter Hofgen
Helmut Euler
Assignee (at issue)
International Standard Electric 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.