Differential Bearing Estimation for RF Tags

TitleDifferential Bearing Estimation for RF Tags
Publication TypeJournal Article
Year of Publication2009
AuthorsLedeczi, A., J. Sallai, P. Volgyesi, and R. Thibodeaux
JournalEURASIP Journal of Embedded Systems
Volume(in press)
Date Publishedxx/2009

Fusing spatially distributed observations in wireless sensor networks or asset tracking in a shipyard are just two example applications where the location of radio nodes needs to be known. Localization and tracking of wireless nodes have been an active research area, yet a universal solution has not emerged so far. This paper introduces a novel method for bearing estimation based on a rotating antenna generating a Doppler shifted RF signal. The small frequency change can be measured even on low cost resource constrained nodes using a radio interferometric technique introduced previously. Bearing information between anchors nodes at known locations and RF tags at unknown positions can be derived. A few such measurements provide enough information to enable accurate node localization.