A Multi-Standard Adaptive Image-Reject Downconverter

摘要

A multi-standard adaptive image-reject downconverter (oscillator and dual mixers) that satisfies the basic requirements of 2nd and 3rd 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 9.9mA for the relaxed mode (2.4GHz DECT) to 20.2mA for the highest performance mode (1.8GHz DCS1800) of operation. The adaptive oscillator achieves -123dBc/Hz and -103dBc/Hz phase noise at 1MHz offset in a 2.1 GHz band for bias current levels of 6mA and 0.5mA, respectively. In the highest performance mode, the image-reject downconverter (quadrature mixers) has an IIP3 of +5.5dBm, single-side band NF of 13.9dB (50Ω) and conversion gain of 1.4dB, while drawing 10mA from a 3V supply.