M.A. Astashkin, B.S. Lobanov, V.N. Denisevich
The relatively low probability of detecting stealth targets by radio-wave security systems - the main problem of the security systems of this type.
In our country, manufacturers are mainly oriented to double station security systems, to a lesser extent present Doppler single station system. The lower limit of the range of detectable velocity of 0.1 m / s, weight not less than 50 kg, height not less than 1 meter.
Foreign producers are guided by wires and radio-wave Doppler security systems, which are laid underground coaxial radiating cable acting as a transmitter and a second cable, laid side by side, acting as a receiver.
The main advantage of foreign radio-wave security systems is the ability to make them invisible. The shortcomings can be attributed again severe restrictions imposed on the parameters of the detected intruder: the lower limit of the range of detectable: the speed of 0.02 ÷ 0.025 m / s, mass 30 ÷ 37 kg.
This article describes an algorithm that considered the case of two mutually perpendicular dipoles (the model of two-position alarm system) located on opposite sides of the insulator. Layered medium is presented in the form of equivalent circuits - cascade-connected as two-port network. Was found, the transmission coefficient, the mutual impedance, which can serve as an informational parameter for intruder detection. Using the algorithm can be reviewed to consider more complicated cases, the construction of the radio wave security systems, such as single station system, located under the ground.