Design issues of direct conversion radio frequency receivers in SiGe technology

The paper describes the design issues of direct conversion RF receivers for WLAN systems using SiGe technology. For direct conversion transceivers, SiGe BiCMOS technology offers a combination of enhanced RF performance with advanced silicon technology. Simulated performance parameters of an active direct down conversion mixer using SiGe BiCMOS MMIC technology are presented. The mixer functions at 5 GHz and draws only 10.2 mW from a 3 V supply. The overall conversion gain of the circuit is 8.5 dB.