Autonomous Positioning Techniques Based on Cramér-Rao Lower Bound Analysis

• Main Authors: Urruela Andreu, Rydström Mats, Ström Erik G, Svensson Arne
• Format: Article
• Language: English
• Published: SpringerOpen 2006-01-01
• Series: EURASIP Journal on Advances in Signal Processing
• Online Access: http://dx.doi.org/10.1155/ASP/2006/93043

<p/> <p>We consider the problem of autonomously locating a number of asynchronous sensor nodes in a wireless network. A strong focus lies on reducing the processing resources needed to solve the relative positioning problem, an issue of great interest in resource-constrained wireless sensor networks. In the first part of the paper, based on a well-known derivation of the Cram&#233;r-Rao lower bound for the asynchronous sensor positioning problem, we are able to construct optimal preprocessing methods for sensor clock-offset cancellation. A cancellation of unknown clock-offsets from the asynchronous positioning problem reduces processing requirements, and, under certain reasonable assumptions, allows for statistically efficient distributed positioning algorithms. Cram&#233;r-Rao lower bound theory may also be used for estimating the performance of a positioning algorithm. In the second part of this paper, we exploit this property in developing a distributed algorithm, where the global positioning problem is solved suboptimally, using a divide-and-conquer approach of low complexity. The performance of this suboptimal algorithm is evaluated through computer simulation, and compared to previously published algorithms.</p>