Optimising sensor placement for site-specific RSSD geolocation systems

Geolocation of wireless emitters using Received Signal Strength Difference (RSSD) and site-specific propagation models offers the advantages of increased accuracy and operation with non-cooperative emitters (where emitted power level or positional information such as GPS from the emitter is unavailable) over more commonplace Received Signal Strength (RSS) systems. An important factor influencing the accuracy of such systems is the physical arrangement of the sensors, making optimising the layout of sensors prior to deployment highly desirable. This paper introduces the novel Uniqueness metric for evaluating receiver layouts based on inter-point RSSD with a site-specific propagation model. Two optimization techniques (Monte Carlo optimization and an implementation of a genetic algorithm) are applied to the metric and evaluated in a case study that incorporates two different propagation environments (urban and rural) compared against an existing dilution of precision based metric. The results of the simulation demonstrate that the uniqueness metric combined with the genetic algorithm provide the best overall performance in both environments tested.