This paper presents a design of a reconfigurable low noise amplifier (LNA) for multiband orthogonal frequency division multiplexing (MB-OFDM) ultra wideband (UWB) receivers. The proposed design is divided into three stages; the first one is a common gate (CG) topology to provide the input matching over a wideband. The second stage is a programmable circuit to control the mode of operation. The third stage is a current reuse topology to improve the gain, flatness and consume lower power. The proposed LNA is designed using 0.18 μm CMOS technology. This LNA has been designed to operate in two subbands of MB-OFDM UWB, UWB mode-1 and mode-3, as a single or concurrent mode. The simulation results exhibit the power gain up to 17.35, 18, and 11 dB for mode-1, mode-3, and concurrent mode, respectively. The NF is 3.5, 3.9, and 6.5 and the input return loss is better than −12, −13.57, and −11 dB over mode-1, mode-3, and concurrent mode, respectively. This design consumes 4 mW supplied from 1.2 V.
A new input matching technique for ultra wideband LNAs