FMCW-CDMA Based Radar-Repeater Network for Enhanced Detection and 2D Imaging of Specular Targets

Detection of specular targets is a significant challenge for single platform radar systems. The mirror-like reflections direct energy away from the radar receiver, reducing the signal-to-noise ratio (SNR) below the detection threshold. Distributed repeaters can help here by increasing the virtual aperture size, that offers spatial diversity and provides additional degrees of freedom. In this work, a 38-39 GHz Frequency-Modulated Continuous-Wave (FMCW) radar system with code modulated distributed repeater architecture is designed to enhance detection capability. The implementation of code multiplexing enable the unique identification of repeater signals even in scenarios where the polarization of reflected signals might change. The simulated and measured results verify the independent separation of repeater response and the experimental results shows improved 2D image and accurate location of a flat-plate specular target, validating the distributed coded-repeater aided radar model.