A 23–40 GHz Compact LNA with Dual-Path Noise-Cancelling Technology Enabled by a Quad-Coil Coupled Transformer

This paper presents a 23–40 GHz low-noise amplifier (LNA) that employs dual-path noise-cancelling technology. The proposed noise-cancelling method, implemented through a quad-coil coupled transformer network, significantly reduces the circuit noise while maintaining a compact layout. To enhance the gain and stability of the circuit, a common-source stage with single-ended neutralization is incorporated after the noise-cancelling stage. Fabricated using TSMC 65-nm CMOS process, the LNA achieves a maximum gain ($S_{21}$) of 15.7 dB, a minimum noise figure (NF) of 2.79 dB, and occupies a chip area of $0.089 \mathrm{~mm}^{2}$. The amplifier operates at a supply voltage of 0.6 V, consuming 14 mW of power.