Passive sensor based on extended Kalman filtering

Passive sensor is an essential receiver-only sensor that usually dissociates the receiving system at different location from the illuminator. This paper investigated a new passive sensor system, the antenna was an 8-element microchip phased array and the non-cooperative illuminator was downlink signals radiated from GSM base station. The digital beam forming technology was used to improve the pattern reconfiguration and to determine the Doppler and phase characteristics of the received signal; the Fast Fourier Transform was adopted for each channel's signal processing. And the system was functionally tested by means of detecting civilian plane near WHITECLOUD airport. The experiment result shows that targets can be detected and tracked over a distance up to 3 km; this system may be used for monitoring the low altitude weapons as an efficient supplementary to urban air defense network. © 2014 IFSA Publishing, S. L.