WiFi-Based Passive Bistatic Radar: Data Processing Schemes and Experimental Results

• Published in: IEEE transactions on aerospace and electronic systems Vol. 48; no. 2; pp. 1061 - 1079
• Main Authors: Colone, F., Falcone, P., Bongioanni, C., Lombardo, P.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2012; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Bistatic radar; Channels; Data processing; Doppler effect; Encoding; IEEE 802.11 Standards; Modulation; OFDM; Receiving; Sidelobes; Signal processing; Spread spectrum communication; Studies; Surveillance
• ISSN: 0018-9251; 1557-9603
• DOI: 10.1109/TAES.2012.6178049

The practical feasibility of a WiFi transmissions based passive bistatic radar (PBR) is analyzed here. The required data processing steps are described including the adopted techniques for 1) the control of the signal autocorrelation function (ACF) usually yielding a high sidelobe level, and 2) the removal of the undesired signal contributions which strongly limit the useful dynamic range. The performance of the proposed techniques is firstly evaluated against simulated data generated according to the IEEE 802.11 Standards. Moreover the results are presented against a real data set collected by an experimental setup when using the conventional dual (reference and surveillance) channels PBR receiving scheme. This allows us to demonstrate the potentialities of a WiFi-based PBR for local area surveillance applications, where vehicles and people can be detected and tracked. Based on the digital nature of the exploited signals of opportunity, the attractive possibility is also investigated of avoiding the use of a dedicated receiving channel for the reference signal, by synthesizing it from the surveillance channel. This approach is shown to yield comparable performance with respect to the conventional PBR approach while yielding a remarkable saving in terms of system complexity.