A 50 MHz ~ 10 GHz, 3.3 dB NF, +6 dBm IIP3 resistive feedback common source amplifier for cognitive radio application

Abstract

Cognitive radio is a smart ultra-wideband wireless communication system that is capable of optimizing the usage of the available frequency spectrum. In this work, an ultra-wideband low noise amplifier with an operating bandwidth from 50MHz to 10GHz with integrated resistive feedback and π-matching network is presented. The amplifier is designed to self-bias via the feedback path to optimize the chip area consumption. The input signal is sourced to two common-source amplifiers to achieve the input matching configuration and subsequently cascaded to another common source amplifier with resistive termination in achieving the output matching. On-chip inductors were adapted to improve the high frequency response and to extend the bandwidth up to 10GHz. Measured results show that the input and output matching are better than −10dB with a gain variation of 10.32–13.28dB, noise figure variation of 3.29–6dB, and a third order intercept point ranging from −3.2 to +6dBm in a frequency span of 50–10GHz on a CMOS 0.13µm platform. The physical layout occupies 0.77mm2 chip area with the bondpads intact and consumes 31.2mW of DC power from 1.2V DC supply headroom.