A 0.1–8.5 GHz wideband CMOS LNA using forward body bias technology for SDR applications

A low power broad band CMOS LNA for software-defined radio (SDR) applications is presented. The LNA is based on the common source cascade amplifier with active feedback. To realize a high gain bandwidth, the inductor shunt peaking technology was used. In order to acquire a good S11 performance over a high frequency band range, a parallel RC network feedback was used too. By using the forward body bias technology, the cascade LNA can operate under 1V supply voltage to reduce the power consumption. The LNA was fabricated using a 90nm RF CMOS technology. The measurement results show that the LNA achieves a bandwidth of 8.4 GHz from 0.1-8.5GHz with a 16.3 dB voltage gain, noise figures from 2.7 dB to 3.9 dB across the whole band, and an input third-order intermodulation product (IIP3) of -4 dBm, the power consumption is about 10 mW without the buffer under the 1V supply voltage.