A Fully-Integrated Band-Switchable CMOS Low Noise Amplifier

This paper proposes a fully-integrated band-switchable low noise amplifier (LNA) which enables three frequency bands of 1GHz, 1.5GHz, and 2GHz by using a proper combination of impedance matching networks at the input and output planes of the LNA. The proposed multi-band low noise amplifier is designed and fabricated in 0.18μm CMOS process with die-size of 3.5mm × 0.9mm. The measured results shows that the proposed band-switchable LNA achieves small-signal gain (S21) of 31dB/31dB/31dB, input reflection coefficient (S11) of −16dB/−14dB/−11dB, and RF saturated output power (Psat) of 10dBm/10dBm/10dBm at 1GHz/1.5GHz/2GHz, respectively. Furthermore, noise figure (NF) of the proposed LNA is observed 3.0dB/3.5dB/3.6dB at the three targeted frequency bands, respectively.