Design methodology of feedback-LNAs for GHz applications

Abstract

~ The design strategy leading to common-base, high linearity feedback-LNAs is proposed. A narrow-band frequency tunable solution and a broad-band one have been designed. Two zero-IF front-ends realized for IEEE 802.11a, HiperLAN2, and HiSWANa including variablegain mixers, show: 2.5dB NF, -9.5dBm IIp3, and 3.4dB NF, -6dBm IIp3 respectively. multistandard wireless LAN applications have been fabricated in a 0.25pm SiGe BiCMOS technology. The first prototype consists of an LNA covering more than lGHz band, by means of 8 tuneable LC narrowhands, followed by quadrature mixers. Measured results, reported in 121, are 2.SdB NF, -9.SdBm IIP3 with a current consumption of 16mA from a 2.5V supply. The second prototype differs for the LNA, which is broad-band. The broad input matching and