RPM and Doppler‐based multi‐path exploitation method for UWB TWR

Through‐the‐wall radar (TWR) with ultra‐wideband (UWB) signals is a promising technology for three‐dimensional monitoring systems used for rescue and security applications. To develop a suitable imaging algorithm to deal with UWB radar data, the range points migration (RPM) method was enhanced for the TWR observation model. However, there are some problems in the actual application because multiple reflection signals from the walls or targets produce a ghost image. This research extends the RPM‐based TWR imaging method to convert a ghost image to an accurate one by exploiting the double‐bounced signals discriminated by the Doppler velocity. Such discrimination can be achieved by prior estimations for the motion and location of the target provided by the Doppler‐associated RPM algorithm. The finite‐difference time‐domain‐based numerical simulation, with the assumption of multiple surrounding walls, demonstrated that the authors proposed method produced an accurate object by converting a ghost image to an actual image.