This paper proposes a multi-input multi-output (MIMO) high-scanning-rate coupled-resonator antennas at millimeter-wave frequency band for 2-D multi-target localization and heartbeat rate monitoring. The designed coupled-resonator antenna is able to vertically scan beam across a 470 angular range as frequency changes from 60GHz to 64GHz, while 3Tx×4Rx MIMO technology can achieve digital beam scann