A 3-5 GHz Low-Complexity Ultra-Wideband CMOS RF Front-End for Low Data-Rate WPANs

This paper presents a 3-5 GHz ultra-wideband radio front-end for low data-rate wireless personal area network applications. The circuit, implemented in a 90-nm CMOS technology, includes a carried-based ultra-wideband transmitter, a sub-optimal coherent down-converter and a low-power LO signal generator. Thanks to a pseudo-Gaussian pulse generator, the transmitter is able to run up to 500 Mpps satisfying the FCC mask requirements with no filter and high spectral efficiency. The down-converter exploits a single-ended low-noise amplifier to minimize power consumption. It also performs on-chip single-ended-to-differential conversion of the RF signal by using an integrated transformer. The down-converter exhibits a 23-dB conversion gain and a double-sideband noise figure of 3.4 dB. The LO signal is generated by a low-power wideband LC VCO, which draws only 1.5 mA. The current consumption of the radio front-end is 15 mA in receive mode and 24 mA in transmit mode.