Measurement and comparative analysis of clutter for GSM and UMTS passive radars

Passive radars have been known to the scientific community since their first application as a system to detect bombers by means of shortwaves radiated by radio broadcasting towers in 1935, although they lately raised a renewed interest among researchers for some specific features that make them more appealing than classic active radar systems. In fact, having the transmitter and receiver located at two different positions, and the adoption of signals carrying other kinds of information such as GSM (either classical or the 1800/1900 MHz DCS version) or UMTS waveforms, makes passive radar virtually undetectable and economically advantageous. A measurement system used to characterise the clutter from a GSM/DCS and UMTS-based passive radar is presented. The main objective is to study the statistical properties of the clutter signals, find theoretical models fitting the measured clutter data and analyse the differences between the modulated carriers of the two different standards.