Cramer-Rao bound analysis of distributed positioning in sensor networks

In future applications of sensor networking technology, it is envisioned that nodes will be able to determine their geographical position by measuring the range differences between one another in a collaborative fashion. The aim of this letter is to provide quantitative expressions that can be used both to facilitate an understanding for why such distributed positioning works and to assess the ultimately achievable accuracy in practice. Specifically, we compute the Crame´r-Rao bound on the positioning accuracy, under different assumptions on the network synchronization. Numerical examples illustrate our results.