A Digital-Calibrated Transmitter-to-Receiver Isolator in Radar Applications

A digital-calibrated isolator for radar is proposed to improve transmitter-to-receiver isolation in this letter. The proposed isolator consists of feedforward and digital-calibrated circuits to cancel the transmitter-to-receiver leakage power. The proposed isolator is implemented in 0.18- $\mu$ m CMOS technology which shows 27.3 dB isolation while consuming 13.5 mW dc power. The ${\rm OP}_{1,{\rm dB}}$ of the transmitter-to-antenna is better than ${+}13.5$ dBm.