Repels: a new rapid deployment guided radar sensor

Abstract

REPELS (Rapidly Extendible Perimeter Line sensor) is a new concept in guided radar perimeter security introduced in 1988. it utilizes a technology termed 'coupled wave device' (CWD) to transfer detection features currently available only to leaky cable buried line sensors, to the above ground, rapid deployment, sensor requirement. Thus, in less than 20 minutes, a person can set up a sensor that establishes a 100-metre long detection barrier (several metres high) about a resource. Like buried line guided radar sensors it provides a terrain-following detection zone and, by operating at VHF frequencies, it also inherently optimizes detection of humans but discriminates against small nuisance targets. This paper addresses some of the physics behind the CWD technology on which the sensor is based, and contrasts this development with other sensor alternatives, including leaky cable sensors. Also discussed is the hardware design of the sensor, including both the electronics and sensor elements. Finally, the paper discusses deployment aspects of the sensor and initial test results for various intrusion scenarios. Typical applications are security for mobile resources such as aircraft and vehicles, dignitary (VIP) security, or temporary stand-in where other sensor zones have failed. Included in the test results is the sensor response to typical human body orientations and to small animals. The REPELS sensor provides a new alternative to allow rapid deployment secur ity for mobile resources and irregular sites.