Wide Field-of-View Locating and Multimodal Vital Sign Monitoring Based on ${X}$ -Band CMOS-Integrated Phased-Array Radar Sensor

In this article, an X -band complementary metal-oxide-semiconductor (CMOS)-integrated phased-array radar sensor is proposed to enable the subject localization and multimodal vital sign monitoring. With the accurate beam-steering (ABS) technique realized by both true-time delay and phase shifting at the transmitter, the phased-array radar sensor achieves 60° steering coverage for the locating and monitoring on the targeted subjects with fine beam-steering precision. With the interferometric time-phase analysis (ITPA) algorithm adopted to the dechirped signal at the receiver, the vital signs and falling are detected by the radar sensor. Fabricated in 65-nm CMOS technology, the radar sensor occupies 5.8 mm ² of silicon area and consumes 740.7-mW power. A series of experiments was carried out to demonstrate the capabilities of the prototype radar sensor on localizing the targeted subjects, discerning vital signs, and detecting falling in a wide field of view (FoV).