DOA-Based Cooperative Positioning in Wireless Sensor Network With Factor Graph Technique

This paper proposes a direction-of-arrival (DOA)-based cooperative positioning system in wireless sensor networks (WSNs), utilizing the factor graph (FG) technique. It aims to deal with the scenario where the anchor nodes, i.e., the sensors, are insufficient, rendering the conventional angle-based schemes unable to provide accurate and unambiguous detection. Specifically, an additional unknown target is incorporated in the FG framework, which is assumed to be capable of forwarding the DOA information obtained from the desired target to the sensors in a cooperative manner. It has been shown that the system performance has been significantly enhanced through target cooperation, in terms of both improved detection accuracy and extended area for reliable service, without requiring additional sensors. The advantages of the proposed system have also been demonstrated compared to other counterpart schemes.