A flip-chip-packaged and fully integrated 60 GHz CMOS micro-radar sensor for heartbeat and mechanical vibration detections

A 60 GHz micro-radar in 90 nm CMOS for non-contact vital sign and small vibration detections was designed and tested. A quadrature receiver embedded in the indirect up- and down-conversion architechture solves the null detection point issue and increases the robustness of the millimeter wave system. In the 60 GHz core, lumped-element-modeled passive components are extensively used to achieve a compact layout (0.73 mm²), and a 36 dB down-conversion gain at 55 GHz. Using low-cost single-patch PCB antennas, flip-chip packaging of the CMOS chip demonstrates high level of system integration. First pass success is achieved as the human heartbeat and a small mechanical vibration with a displacement of 20 μm can be detected at 0.3 m away. With a roughly one-tenth patch antenna size compared to previously reported works, the 60 GHz CMOS integrated micro-radar can be readily embedded in various portable devices to detect vary small vibrations and used for many applications.