Range estimation using phase difference of arrival technique

Abstract

The principle of positioning is a technology of identification that enables object, people and/or assets to be tracked. This is basically to allow objects to be found for the purpose of rendering/obtaining services. Ranging technique therefore is an important part in anchor nodes location vis-à-vis the distance between anchors to the blind node. Integration of location capability into Wireless Sensor Network provides enablement in the location of network devices anywhere in the area of deployment, thereby making the network more valuable from the point of view of the application. Currently, there are several techniques which have been used to estimate ranges, most of the approaches which are dependent on a single frequency technique and those techniques are inaccurate in estimating the range, particularly in a multipath environment. The proposed work was to employ a dual-frequency phase difference of arrival technique for one-way propagation to capture ranges. Phase Difference of Arrival technique is a dual-frequency technique of ranging that offers better solution than already available single frequency ranging techniques. The technique has previously been used for radar application. Having evaluated the performance of this new technique for different frequency pairs with different frequency separation in different noise variance level, proof of the concept is provided using simulated data. The obtained results show that the proposed dual-frequency Phase-Difference of Arrival system is able to correctly find the location of, and track objects. Ranging simulation results show that frequency separation of 50MHz is best suited for one-way short-range application.