A 0.18-μm CMOS fully integrated antenna pulse transceiver with leakage-cancellation technique for wide-band microwave range sensing radar

This paper presents a leakage cancellation technique for on-chip transceiver for range sensing radar. A 180-nm CMOS transceiver with on-chip antennas is implemented with a 9-11-GHz damping-pulse transmitter (Tx) and a receiver (Rx) including a mixer and a 3-stage low-noise amplifier (LNA). By adding a polarity-reversal switch to the receiver mixer, leakage, reflected signals, and traveling time of transmitted pulses can be measured. Another improvement is the design of the Rx´s mixer and the 3-stage wide-band LNA to reduce on-chip DC blocking capacitors. Experimental results with/without reflector placed at several distances from the transceiver are performed to demonstrate the technique. Pulse traveling times are measured with 0.8 ns, 1 ns, and 1.25 ns for the distance of 10 cm, 14 cm, and 18 cm, respectively. Furthermore, reflected signals are measured separately from leakage in cases of different distances.