Digital post-linearization of a Wideband Low Noise Amplifier for ultra-wideband wireless receivers

The scaling of CMOS Low Noise Amplifiers (LNA) comes with a reduction in supply voltage and increase in field mobility effect resulting in deterioration in linearity. This trade- off between CMOS transistor scaling and linearity is becoming more and more important as we transition into nano-scale CMOS LNA architectures. As a result, new techniques for the linearization of LNAs while maintaining an above average impedance matching, noise figure, power consumption, and gain are required. In this paper, we propose a novel technique for the adaptive post-distortion of a low power capacitor cross-coupled common gate low noise amplifier which results in compensation of the LNAs third order inter-modulation (IM3) product.The proposed technique is shown to provide excellent improvement in the third order input intercept point (IIP3) with the third order inter modulation tone running parallel with the fundamental tone over a 3 GHz to 10.6 GHz frequency range in a two tone test.