Communications: electrical – Condition responsive indicating system – Specific condition
Patent
1975-10-31
1980-06-10
Swann, III, Glen R.
Communications: electrical
Condition responsive indicating system
Specific condition
340531, 340540, 356 731, 455612, G08B 2100
Patent
active
042075610
ABSTRACT:
An intelligence modulated optical beam is injected into an optical waveguide through a beam splitter. At the output end of the optical waveguide the optical beam has a portion thereof transmitter through a partial reflector to a detector or receiver with a portion of the optical beam at the output of the waveguide being reflected back into the waveguide with the reflected beam being reflected by the beam splitter to a correlator. A replica of the intelligence of the injected optical beam delayed an amount equal to the round trip transit time of the optical beam is supplied as the other input of the correlator. The delayed replica of the intelligence of the optical beam and reflected optical beam are correlated to produce an output from the correlator proportional to the attenuation or intensity of the reflected beam. When the output of the correlator falls below a given value, an alarm is actuated indicating that an intruder has intercepted intelligence of the optical beam transmitted through the waveguide.
REFERENCES:
patent: 3134840 (1964-05-01), Gamo
patent: 3135951 (1964-06-01), Byrne
patent: 3698820 (1972-10-01), Hanff et al.
patent: 3717769 (1973-02-01), Hubbard et al.
patent: 3832061 (1974-08-01), Smith et al.
Hill Alfred C.
International Telephone and Telegraph Corporation
O'Halloran John T.
Swann III Glen R.
LandOfFree
Intruder alarm arrangement for an optical communication system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Intruder alarm arrangement for an optical communication system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Intruder alarm arrangement for an optical communication system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-865944