Experimental Demonstration of Multi-stage Leakage Mitigation techniques in Ku-band CW Radar

Transmitted signal leakage to the receiver section in continuous wave (CW) radar is a serious concern due to poor isolation between the transmitter and receiver chain. Mitigation of leakage signals and successful operation of CW radar in the presence of a leakage signal is the primary focus of this manuscript. In this work, multi-stage leakage mitigation strategies have been adopted to effectively nullify the leakage signal. To achieve this target, transmitter-to-receiver antenna leakage has been reduced by using an absorber sheet, base-band leakage signal has been rejected by using a band-pass filter and the rest of the leakage signal has been rejected by using DC offset cancellation in digital signal processing (DSP). The effectiveness of these techniques has been validated by implementing them in a Ku-band CW radar. Experimentally, this radar has demonstrated a leakage suppression of 46 dB and sensitivity improvement of 32 dB.