A Low-Power Reconfigurable Narrowband/Wideband LNA for Cognitive Radio-Wireless Sensor Network

This article proposes a low-power reconfigurable multimode low-noise amplifier (LNA) that can be configured for multiple narrowband as well as wideband operations while providing simultaneous input matching and output load reconfigurabilty. A component sharing technique and a component-Q-aware impedance-matching technique are introduced in the proposed LNA circuit. The proposed LNA, implemented in a United Microelectronics Corporation (UMC) 0.18-μm CMOS process, can operate in a narrowband mode with center frequencies around 1.8, 2.1, and 2.4 GHz as well as in a wideband mode (2-5 GHz). Measured results show that the LNA has achieved 14.1, 14.5, and 14.1 dB of voltage gain, 8.5, 8.2, and 8.7 dB of noise figure (NF) in 1.8-, 2.1-, and 2.4-GHz modes, respectively. In the wideband mode, the measured gain and the NF are 14.5 and 7.8 dB, respectively. The LNA consumes 2 and 3.8 mW of power from the 1.8-V supply in the narrowband and wideband modes, respectively.