Abstract
In this article, we propose a step-by-step deployment algorithm of the localization reference sensors in wireless sensor networks, in order to minimize the mean-square error of the physical coordinates of the located objects, for both cases of users and blind-folded sensors those use received- signal strength applications. The physical coordinates of reference sensors can be obtained by global positioning system, etc. The deployment algorithm is designed to have low complexity and high flexibility to non-homogeneous environment. To simplify the performance calculation of a deployed network, we apply Cramér-Rao Bound as a substitute of the mean-square error of localization algorithms, in order to avoid the large amount of calculation and obtain generality to localization algorithms. The main object of this article is to verify the performance of the deployment algorithm, and this is done by making comparison between the result of proposed algorithm and some significant benchmarks. The short-term characteristics of the proposed algorithm with respect to the numbers of reference nodes are proved by comparing with exhausted search. Moreover, the long-term characteristics of the proposed algorithm with respect to the numbers of reference nodes are proved by comparing with many other benchmarks, those are designed in consideration of the nature of deployment. By these comparisons, we find that the performance of the proposed algorithm converges to the best performance very fast. Then, we modify the deployment algorithm, in order to lower down the complexity of the original algorithm, and do performance comparisons. Last, we apply a very general localization algorithm – maximum likelihood estimations to confirm if it is suitable to substitute the performance of localization algorithm by Cramér-Rao Bound. We obtain that Cramér-Rao Bound can be treated as an accurate substitute of the performance of localization algorithms