Patent ID: 8780007

Claim:
A planar antenna, comprising: a radiator, comprising: a first portion comprising a first contact point and a second contact point; a second portion comprising a third contact point, a fourth contact point electrically connected to the second contact point, and a fifth contact point; and a third portion comprising a sixth contact point; a screening element, being electrically connected between the fifth contact point and the sixth contact point to make the planar antenna operating in a first high-frequency (HF) current path and a first low-frequency (LF) current path; and a switch, being electrically connected between the first contact point and the third contact point to make the planar antenna operating in a second HF current path and a second LF current path; wherein when the switch is turned off, the planar antenna operates at a first HF central frequency corresponding to the first HF current path and a first LF central frequency corresponding to the first LF current path at the same time, and when the switch is turned on, the planar antenna operates at a second HF central frequency corresponding to the second HF current path and a second LF central frequency corresponding to the second LF current path at the same time.