A High-Gain, Low-Noise 3.1–10.6 GHz Ultra-Wideband LNA in a 0.18μm CMOS

An ultra-wideband (UWB) common gate-common source (CG-CS) low-noise amplifier (LNA) in a 0.18μm CMOS technology is presented in this paper. A capacitive cross-coupling fully differential amplifier with the current-reuse technique is described that in the entire 3.1–10.6 GHz UWB band, achieves a high and flat power gain with low noise and good input impedance matching among low power consumption. The current–reuse technique is used to achieve a wideband and reduce the power consumption. The capacitor cross coupling technique is used to gm-boosting and hence to improve the NF of the amplifier. Therefore, the dependency between noise figure (NF) and input impedance matching is reduced. The proposed CG-CS amplifier has a fairly low NF compared with the other previous works in similar technology. In addition, a good power gain over all bandwidth and a high isolation with good input/output impedance matching are achieved. The minimum NF is 1.8 dB, the maximum power gain is 14.2 dB, the inverse gain is <-50 dB, and in the entire 3.1–10.6 GHz UWB band, the input and output matching S11 and S22 are < -10.3 dB and <-11.3 dB, respectively. The input third-order intercept point (IIP3) is -5 dBm. Moreover, the power consumption of the core is 10.1 mW with the supply voltage of 1.8 V.