When: Friday, February 17, 12:00 p.m.
Where: 1507 Newell-Simon Hall
Andreas Krause
Abstract:
When monitoring spatial phenomena with wireless sensor networks, selecting the best sensor placements is a fundamental task. Not only should the sensors be informative, but they should also be able to communicate efficiently. In this talk, I will present our data-driven approach that addresses the three central aspects of this problem: measuring the predictive quality of a set of sensor locations (regardless of whether sensors were ever placed at these locations), predicting the communication cost involved with these placements, and designing an algorithm with provable quality guarantees that optimizes the NP-hard tradeoff. Specifically, we use data from a pilot deployment to build non-parametric probabilistic models called Gaussian Processes (GPs) both for the spatial phenomena of interest and for the spatial variability of link qualities, which allows us to estimate predictive power and communication cost of unsensed locations. Using these models, we present a novel efficient algorithm, pSPIEL, which selects Sensor Placements at Informative and cost-Effective Locations. Exploiting two important properties of this problem — submodularity and locality — we prove strong approximation guarantees for our pSPIEL approach. We also provide extensive experimental validation of this practical approach on several real-world placement problems, demonstrating significant advantages over existing methods.
