Single-site source localisation using scattering data

Passive localisation of non-cooperative targets through their electromagnetic emissions is an attractive issue. This localisation task can be carried out using multitude of receiver sites being linked together. This multiplicity, however, brings about difficulties in organising and coordinating the sites. One can even claim that the method is no longer passive considering the necessary communication links between the sites. On the other hand, single-site localisation methods basically overcome these difficulties eliminating the need for inter-site communications. In this study, a single-site localisation method is presented and analysed. This method is applicable to scenarios with a large known object which plays the role of an electromagnetic wave scatterer. The single receiver site receives both direct and scattered waves through two different antenna systems and analyses them to localise the target. Electromagnetic simulation using the finite-difference time-domain method was applied to the problem showing good agreement with the theoretical results. The present study also investigates the effects of noise on the accuracy of localisation. Some of the important practical considerations of the method, like the electromagnetic modelling of the dominant scatterer, are also discussed.