A Low-Power, Low-Noise Common-Gate LNA with Negative-Positive Feedback in FD-SOI for Harmonic Rejection N-Path Mixer Systems

This paper presents a common-gate low-noise amplifier (CG-LNA) incorporating negative and positive feedback loops, implemented in FD-SOI technology. Our CG-LNA achieves a simulated gain exceeding 21 dB across the 370 MHz to 1.5 GHz frequency range, while maintaining a minimum noise figure of 1.7 dB and an ultra-low power consumption of 1.1 mW. The amplifier achieves a high output impedance effectively driving 8 fully differential amplifiers in the framework of an harmonic rejection 4-path mixer (HR-NPM), minimizing noise contributions and power overhead of the full receiver. Results confirm that the proposed LNA is well-suited for HR-NPM LNA-first receiver architectures, offering an optimal trade-off between gain, noise performance, and power efficiency.