A 1.8GHz BiCMOS RF receiver IC taking into account the cross modulation for CDMA wireless applications

This paper presents a 1.8GHz RF receiver chip taking into account the cross modulation inherent in CDMA mobile phones. The quantitative analysis shows the design guidelines for duplexer loss and LNA IIP3, both of which are responsible for the cross modulation. They are applied to a 1.8GHz RF chip design using 0.5µm BiCMOS technology, which includes LNA, mixer, and variable gain amplifier. The measured cascaded noise figure is 3.5dB and cascaded IIP3 is -9dBm and LNA IIP3 is +4.3dBm at 1.85GHz.