SiGe front-end transceiver components for 802.11a WLAN applications

This paper presents the design and fabrication of 5-GHz Tx/Rx RF front-end components for IEEE 802.11a WLAN using 0.5 μm SiGe BiCMOS technology. All degeneration inductance employed only the down-bond inductors, and all matching circuits were employed on chip design except the input DC blocking capacitors. The effects of feedback resistance in the LNA on gain, input match, noise figure, and IP3 performance are investigated. The packaged LNA exhibited an NF of 2.5 dB with a gain of 16.5 dB at 5.25 GHz and an IIP3 of -10.5 dBm. The Rx/Tx mixers exhibited conversion gains of -2.1/-8.3 dB and IIP3s of 0.0/2.4 dBm, respectively. The driver amplifier achieved a gain of 26.5 dB and an OIP3 of 19.8 dBm. The overall NF and IIP3 of receive chain (from antenna to Rx mixer) were estimated to be 6.5 dB and -12.8 dBm, respectively.