A 28-GHz one-bit direct-detection based MIMO receiver with wireless LO distribution is presented. Unlike a conventional MIMO structure, which requires wired LO distribution with power-hungry on-chip LO buffers and phase generators, in this work, the antenna receives both RF and the broadcast single-ended LO and directly converts them to an IF signal by using a simple low-power square-law detector. An LNA with a notch filter is designed to help reduce the non-idealities that appear when the input LO power is lower than that of the RF. A 1 GS/s symbol rate with a high error-vector magnitude is achieved with a power consumption of 33 mW by using a 0.18um SiGe BiCMOS process.