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.