Three Estimation Methods for RSSI-based Localization with Multiple Transmit Antennas

In a radio signal strength indicator (RSSI)-based localization with multiple transmit antennas, a target node with unknown coordinate is equipped with multiple antennas and transmits packets to anchor nodes with known coordinates, selecting one antenna out of them in a round robin manner. On the other hand, anchor nodes measure the RSSIs of received packets and send the measured data to a sink node, and finally, a computer estimates the location of the target node according to a maximum likelihood (ML) method. This paper discusses three estimation methods; joint, simplified and approximated estimation methods and compares the three estimation methods in term of the root mean square (RMS) estimation error.