Multiple Human Targets Detection and Localization Using Leaky Coaxial Cable Sensing Technique

Leaky coaxial cable (LCX) not only widely applies to the wireless communication systems, but also used as a LCX sensor for the intrusion detection systems (IDS). For evaluating the usability of the specialized LCX, the electrical parameters and the radiation pattern of the LCX sensor are measured. Moreover, in order to achieve the multiple targets localization, the novel location algorithm is proposed for the IDS based on the specialized LCX sensor in the VHF band. In this paper, the multiple targets are identified precisely by the synchronous subtraction, the time-domain digital pulse compression and the window function. By emitting a chirp signal into the LCX sensor, the echo signal containing the targets’ response is received by the signal receiver (Rx). Then the pulse accumulation can be used for decreasing the noise signal in the digital signal processor (DSP), and the peak characteristics of the targets’ echo signal are improved by the pulse compression and the Kaiser window function. Finally, by calculating the delay time of the echo signal after using the synchronous subtraction, the targets locations are obtained. The results show that transmission attenuation of the specialized LCX is 0.75 dB/100m and its coupling Loss is 71.63dB, and S11 is -39.9dB when the central frequency is 100MHz. The range resolution of the intruder detection system based on LCX sensor is as small as 3.32m and the positioning accuracy is less than 0.8m, which realizes the multiple targets detection and good localization results.