A CMOS low-noise amplifier for spectral sensing in cognitive radios

In this paper, we present a new wideband low noise amplifier which operate in UHF band for spectral sensing in the receiver of cognitive radios. The circuit employs the noise-canceling technique, and can achieve the higher gain and lower power dissipation. The method of shunt-resistive feedback is adopted for achieving a broad bandwidth. The LNA is designed by the CMOS 0.18 um RF technology. Simulated results show that the gain is 18-21 dB, the noise figure is less than 4 dB, and the LNA consumes only 11.2 mW at 1.8 V power supply.