Embodiments of antennas and radio frequency (RF) modules include a substrate, a first antenna arm coupled to the substrate, and a first conductive structure between a distal end of the first antenna arm and a bottom surface of the substrate. An embodiment of a system includes a first substrate, a first conductive structure on a top surface of the first substrate, and an antenna coupled to the top surface of the first substrate. The antenna includes a second substrate, a first antenna arm coupled to the second substrate, and a second conductive structure having a proximal end and a distal end. The proximal end of the second conductive structure is coupled to a distal end of the first antenna arm, and the distal end of the second conductive structure extends to a bottom surface of the second substrate and is coupled to the first conductive structure on the first substrate.