Low-power UWB LNA with common-gate and current-reuse techniques

A common-gate (CG) low-noise amplifier (LNA) that uses the current-reuse technique and is intended to achieve both ultra-wideband and low-power consumption is proposed. The CG amplifier enables wide-band input matching with low transconductance and low frequency-independent noise figure (NF) when employed at the input stage compared with the common-source amplifier. The current-reuse technique is adopted in order to reduce the power dissipation while achieving reasonable power gain. In addition, a shunt and series peaking technique is adopted to obtain wide bandwidth. The proposed LNA achieves a 3-dB bandwidth from 2.4 to 11.2 GHz, a maximum power gain of 14.8 dB, a minimum NF of 3.9 dB and a third-order input intercept point of -11.5 dBm while consuming 3.4 mW from a 1.5 V supply. A 0.18-μm CMOS process is utilised to fabricate the LNA.