SwarmNet: A distributed navigation network using Ultra Wideband ranging and communications

Ultra Wideband (UWB) radios use a pulsed-RF signaling structure to provide multipath-resistant peer-to-peer distance measurement between radio transceivers. Recent breakthroughs have introduced small, low power, and highly accurate ranging radios to the market. This paper reports a mathematical and algorithmic foundation for networking these transceivers such that the driving force behind the network optimization is no longer data throughput or routing, but instead localization accuracy. This tightly-coupled navigation scheduler and communication protocol has been dubbed “SwarmNet”. The SwarmNet framework combines error-driven scheduling with navigation accuracy optimization through distributed Extended Kalman Filters (EKF) with novel sharing of location and error covariance across neighboring nodes. Experimental testbed results show slotted ALOHA capacity can be sufficient when other navigation sensors are utilized. Simulation of multiple cooperative nodes demonstrate “accuracy flooding” where transient dimensional accuracy is propagated through independent mobile agents.