A Low Power Wideband Receiver Front End for C/X Band 5G Applications in 90 nm CMOS Technology

This paper presents a fully integrated receiver (Rx) front end designed for the coexistence of a $5 \mathrm{GHz} 802.11 \mathrm{ac}$ WiFi system and emerging 5G wireless communications. The Rx front end consists of a low noise amplifier (LNA), Balun, passive mixer, and low-pass trans-impedance amplifier (TIA) for baseband channel selection. The LNA is implemented using an inverter-type LNA with transformer feedback to achieve high integration, wideband operation, and higher transconductance $\left(g_{m}\right)$ compared to a common source (CS) amplifier. The key objective is to optimize performance in terms of high conversion gain, low noise figure (NF), and low power consumption. The fabricated Rx front end, utilizing $\operatorname{tsmc}^{\mathrm{TM}} 90-\mathrm{nm}$ CMOS technology, demonstrates a conversion gain of $32 \mathrm{~dB}$, an NF of $2.47 \mathrm{~dB}$, and a 35MHz channel bandwidth, all while consuming only $24 \mathrm{~mW}$ of power. The chip occupies an area of $0.63 \mathrm{~mm}^{2}$.