A multi-standard adaptive image-reject downconverter

A multi-standard adaptive image-reject downconverter (oscillator and dual mixers) that satisfies the basic requirements of 2/sup nd/ and 3/sup rd/ generation wireless standards (i.e., DCS1800, W-CDMA, 802.11b, Bluetooth and DECT) is presented. The adaptivity between the standards is achieved by trading RF performance for current consumption, ranging from 9.9 mA for the relaxed mode (2.4 GHz DECT) to 20.2 mA for the highest performance mode (1.8 GHz DCS1800) of operation. The adaptive oscillator achieves -123 dBc/Hz and -103 dBc/Hz phase noise at 1 MHz offset in a 2.1 GHz band for bias current levels of 6 mA and 0.5 mA, respectively. In the highest performance mode, the image-reject downconverter (quadrature mixers) has an IIP3 of +5.5 dBm, single-side band NF of 13.9 dB (50 /spl Omega/) and conversion gain of 1.4 dB, while drawing 10 mA from a 3 V supply.