Example embodiments relate to 3D phased array-antenna systems and devices. A system may include a 3D structure with its center located at an origin of a reference coordinate system that includes an X-axis, a Y-axis, and a Z-axis extending from the origin of the reference coordinate system. The system may also include antenna arrays that have antenna elements configured to operate via electronic steering. The antenna arrays can be coupled to the 3D structure such that electronically steering antenna elements of the antenna arrays enables the antenna elements to transmit and receive electromagnetic signals simultaneously in numerous directions relative to the X-axis, the Y-axis, and the Z-axis of the reference coordinate system. The system may be used in various applications, including data transmission and reception, radar, and broadband signaling.