A Fully CMOS Integrated Transmitter for Wireless LAN Applications

Featuring a direct-conversion architecture,a 2.4-GHz radio-frequency(RF) transmitter front-end for 802.11b wireless LAN(WLAN) is implemented in 0.18-μm CMOS technology.The transmitter incorporates two low-pass filters(LPFs),a single-sideband(SSB) mixer,a power amplifier(PA) driver and a divide-by-two circuit for quadrature LO generation.The transmitter provides a gain control of 12 dB in 3-dB steps and an output 1-dB compression of 7.7 dBm while delivering a nominal output power of 0 dBm.The chip consumes 40 mA of power from a 1.8-V supply and occupies an area of 1.8 mm×1.5 mm,excluding pads.