A compact planar inverted-F antenna (PIFA) has been designed, fabricated, and characterized to work either for receiving or transmitting applications. The antenna center frequency can be tuned from 1.52 up to 2.25 GHz, using switched auxiliary strips. Ohmic contact radio frequency microelectromechanical system (RF-MEMS) switches are used to connect and disconnect the auxiliary strips, maintaining both efficiency and antenna linearity (power handling capability). The measured PIFA efficiency for all states in an anechoic chamber is between 52% and 95%. The antenna linearity has also been measured using an adjacent channel power ratio test bench, showing 42-dB dynamic range up to 28-dBm input power.