Patent attributes
A handheld device and a planar antenna thereof are provided. The planar antenna comprises a radiator with an open terminal, a short terminal, a first feeding terminal and a second feeding terminal. The short terminal is coupled to a ground terminal. The first feeding terminal is formed between the open terminal and the short terminal, and coupled to a radio frequency (RF) signal terminal. The second feeding terminal is formed between the open terminal and the first feeding terminal, and coupled to the first feeding terminal by a transmission line and a switch element. The radiator resonates at the first central frequency when the switch element is turned off, and resonates at the second central frequency when the switch element is turned on.
