An antenna subsystem includes an antenna and a radio frequency (RF) feed structure. The antenna subsystem includes a signal layer, a ground plane layer, and a middle layer arranged therebetween. The RF feed includes a substrate, a port, and a conductive layer. The port is arranged and configured for selective coupling with a transmission line. A conductive layer includes a first portion electrically connected to the port, which transfers an RF signal between the transmission line and a signal layer. The conductive layer also includes a second portion electrically connected to the port, which electrically couples a ground conductor of the transmission line to the ground plane.