A power efficient bandwidth regulation technique for a low-noise high-gain RF wideband amplifier

In this paper, a single-stage deep sub-micron wideband amplifier (LNA) using a reactive resonance tank and passive port-matching techniques is demonstrated operating in the microwave frequency range (K band). A novel power-efficient bandwidth (BW) regulation technique is proposed by incorporating a small impedance in the resonance tank of the amplifier configuration. It manifests a forward gain in the range of 5.9-10.7 dB covering a message bandwidth of 10.6-6.3 GHz. With regulation, input-output reflection parameters (S-11, S-22) and noise figure can be manipulated by -12.7 dB, -22.7 dB and 0.36 dB, respectively. Symmetric regulation is achieved for bandwidth and small signal gain with respect to moderate tank impedance (36.5% and -26.8%, respectively) but the effect on noise contribution remains relatively low ( increase of 7% from a base value of 2.39 dB). The regulated architecture, when analyzed with 90 nm silicon CMOS process, supports low power (9.1 mW) on-chip communication. The circuit is tested with a number of combinations for tank (drain) impedance to verify the efficiency of the proposed technique and achieves better figures of merit when compared with published literature.