04458240 is referenced by 10 patents and cites 1 patents.

An electronic detection system for detecting intrusion thru a perimeter eoys a transmission line as a sensing element. In one embodiment, RF energy is transmitted: in another, pulses of DC. In either case, pseudo-random coding of the signals is employed. A preferred emboidiment of the invention utilizes a transmission line consisting of a twisted pair of wires enclosed in a non-deformable insulation and configured for shallow burial to effect concealment. Another shape is disclosed for laying-out over hard ground. A low ohmic ground is included under the line to improve performance. An intruder in the field of the line causes an RF reflection back towards the source, which reflection may be detected by Doppler range-gating techniques.

Title
Energy wave electronic intruder detection system
Application Number
840206
Publication Number
4458240
Application Date
August 31, 1981
Publication Date
July 3, 1984
Inventor
Reinhard G Olesch
Kronberg
DE
Otto E Rittenbach
Monmouth County
NJ, US
Agent
John W Redman
Jeremiah G Murray
Anthony T Lane
Assignee
The United States of America represented by the Secretary of the Army
DC, US
IPC
G08B 13/24
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