A low-voltage CMOS downconversion mixer for RF applications

In the framework of a project aimed at realising a CMOS RF front-end receiver for DECT applications, a low-voltage, highly linear downconversion mixer has been realised. It consists of a quad differential pair, with resistive degeneration, implemented with MOS transistors in the linear region. The core mixer drains 3.8mA from a 2.2V supply; its conversion gain, third order input intercept point (IIP3) and noise figure are given, respectively, by -2.5dB, 21dBm and 21dB.