A Survey on DoA Measurement using ULA and UCA for Wireless Sensor Network Applications

In Wireless Sensor Network (WSN) applications location information of the node is a critical issue. Node location estimation algorithms are developed using radio frequency characteristics such as Received signal strength (RSSI), Direction of Arrival (DOA) or Angle of arrival (AOA), Time of Arrival (TOA) and Time difference of arrival (TDOA), for position estimation application of sensor node in a WSN environment. Although RSSI based location estimation is less complex, the DoA measurement has also gained popularity in WSN applications. In this article, a focused survey of various techniques used to measure Direction of Arrival based on the antenna array geometry like Uniform Linear Array (ULA) and Uniform Circular Array(UCA).