A Compact Low-Loss Bi-directional Amplifier for Ku-band

Conventional bi-directional amplifiers connect transceiver circuits through two T/R switches that are large in area and introduce some loss at high frequencies. In this paper, a compact low-loss bi-directional amplifier for Ku-band (receive: 12-13 GHz, transmit: 15.5-16.5 GHz) has been designed on a TSMC 65 nm 1P9M CMOS process and employs two triple-coil-coupled transceive matching network multiplexing transformers to connect transceiver circuits. When the circuit is in the transmitting state, the power amplifier achieves a 1 dB compression point of 6.321 dBm and the peak PAE is close 30%. When the circuit is in the receiving state, the low-noise amplifier boasts a remarkable in-band gain exceeding 25.7 dB, accompanied by a NF of less than 3.5 dB. The area of the triple-coil coupling transformer is approximately 200*200 $\mu \mathbf{m}^{\mathbf{2}}$, which reducing the overall area of the bi-directional amplifier. The high-frequency insertion loss of the structure is about 1 dB, which is less than the 2 dB insertion loss of conventional switches at high frequencies. This design can be widely used in Ku-band phased array radars.