A SiGe-BiCMOS UWB Receiver for 24 GHz Short-Range Automotive Radar Applications

This paper presents a SiGe receiver IC for 24 GHz short-range automotive radar based on pseudo-noise code modulation. An on-chip 48 GHz LC-VCO plus frequency divider generate the 1/Q clock signals for zero-IF down-conversion. The 24 GHz output signal of the first frequency divider is available off-chip as carrier for the accompanying transmitter IC. The IC includes two LNAs with built-in single-ended to differential conversion. On-chip coplanar transmission lines on a ground shield are used extensively throughout the IC for distribution of RF and clock signals. The 1.5x1.7 mm² receiver IC is implemented in a SiGe:C BiCMOS process with f tau/fmax = 130/140 GHz. The IC achieves a measured DSB noise figure below 7 dB across a 2.5 GHz DSB IF bandwidth, with a conversion gain of 39 dB.