A 1.5-V CMOS receiver front-end for 9-band MB-OFDM UWB system

This paper presents the design of a CMOS Receiver Front-End (RFE) with dual-conversion zero-IF architecture for Multi-Band OFDM (MB-OFDM) system covering the first 9 frequency bands from 3.1 GHz to 8.0 GHz, each with a bandwidth of 528 MHz. A 3-stage wideband variable-gain LNA and a novel mixer with bottom LO input devices are proposed. A fully integrated frequency synthesizer is included to generate the desired LO signals with a band switching time of less than Ins. Fabricated in TSMC 0.18-mu m CMOS process and operated at 1.5 V, the RFE measures a maximum noise figure of 8.1 dB and an inband IIP3 of -11.1 dBm while consuming a total current of 81.5 mA.