Abstract—Based on the dual-path cancellation methodology, a noise cancellation technique and an insertion loss mitigation technique are presented to improve the properties of the active quasi-circulators. The proposed circulator is fabricated in a standard 0.18 μm CMOS process, occupying an area of 0.91 mm × 0.49 mm including the pads. Measurement results show that 34 dB isolation is obtained over a wide frequency range from 1 to 8 GHz, while the insertion loss is below 2.5 dB and the noise figure (NF) is less than 10 dB.