For an autonomous mobile robot in indoor environment, precise sensing of its surroundings is essential to enable safe operation, where comprehensive and cognitive perception capability is needed for the robot to recognize human subjects in a complex and environment to avoid collision. Moreover, comprehensive sensing is needed to enable accurate simultaneous localization and mapping (SLAM) under scenarios with clutters and moving human subjects. By leveraging the phased-array radar techniques and phase processing techniques, high accuracy can be achieved for localization and recognizing human subjects. Fabricated in 65-nm CMOS technology, the chip-scale sensing platform is within 1W power consumption, paving the way for seamless robust human-robot interactions.