Using VHF Navigation Aid to Estimate Radar Cross Section of Airliners by Inverting the Radar Equation

The VHF Omnidirectional Range (VOR) navigation aid system can be used as donor of signal for passive radar experiments. An experiment was set up close to a VOR beacon to detect airliners and to analyze their radar cross section in function of their attitude. This paper presents the configuration of the trials, the adapted signal processing and the detection results obtained for one of the detected targets. The radar cross section (RCS) was estimated from the computation of power budget in radar equation. An analysis of the evolution of the RCS is given in function of the attitude of this detected target in azimuth and elevation. Mean values of RCS for many models of airliners detected during the trial campaign and deduced by the same approach are then presented.