Time-Domain Analog Front-End for UWB WLAN Transform-Domain Receiver

This paper addresses the problem of the time-domain direct-sequence front-end for transform-domain ultra-wideband (UWB) wireless local area network (WLAN) receiver. The proposed architecture comprises a single-ended voltage-voltage dynamic feedback low-noise amplifier (LNA), quadrature mixer, and baseband filter. The dynamic feedback with inductive output load reduces the LNA to a simple second-order filter, with zero at the origin, while improving the conversion gain (CG), noise figure (NF). Thus, the CG is further maximized when limiting the two poles within the 5-6 GHz frequency band. The mixer, based on a merged quadrature topology, employs single-peak notch network, with benefits to the CG, NF, and IIP3. The front-end, drawing 10, 9 mA form 1.8 v, achieves at 5.6 GHz 34.8 dB conversion gain, 12.1 dB noise figure, and 1-dB gain desensitization with -8 dBm interferer power at 7 GHz. Other simulation results are -2.35 dBm minimum IIIP3, and -35 dBc rejection at the UWB groups #1 and #3.