Planar inverted-F antennas, and modules and systems in which they are incorporated

An embodiment of an antenna includes a radiation frame and a planar inverted-F antenna (PIFA). The radiation frame has a frame shape that defines a central opening. The PIFA includes an antenna arm, a feed arm, and a shorting arm. A distal end of the shorting arm is conductively coupled with the radiation frame. The antenna may be coupled to a substrate of an RF module. The RF module may be included in a system that also includes a non-RF component that produces a signal for transmission. In such a system, the RF module is configured to receive the signal, convert the signal to an RF signal, and radiate the RF signal over an air interface.