Wireless sensor network with 24 GHz local positioning transceiver

This paper reports on an innovative cooperative wireless localization network layout and the design of its network nodes. Each node consists of a 24 GHz FMCW secondary radar for bilateral range measurements between all nodes. Network synchronization and scheduling is based on IEEE 802.15.4 radio units. A novel concept to distributedly pre-synchronize all network nodes with an error of less than 125 ns was implemented and combined with the 24 GHz local positioning radar. With prototypes of the sensor nodes a ranging precision of about 1 cm is demonstrated experimentally.