Electronic device

An electronic device, comprising:

• a tunable antenna;
• a radio frequency signal transceiving module, coupled to the tunable antenna, and transmitting at least one radio frequency signal through the tunable antenna;
• a coupler, coupled between the tunable antenna and the radio frequency signal transceiving module, and coupling the at least one radio frequency signal to derive a coupling signal;
• and
• a control unit, receiving the coupling signal, and generating at least one control signal according to a signal strength of the coupling signal in a specific frequency band, and outputting the control signal to the tunable antenna to adjust a working frequency band of the tunable antenna;
• wherein the tunable antenna comprises:
• an antenna body, comprising a feed-in terminal, a ground terminal, a first open terminal, and a second open terminal;
• a first capacitor set, coupled between the first open terminal of the antenna body and a system ground plane, a control terminal of the first capacitor set being coupled to the control unit, and comprising a first capacitor and a second capacitor coupled to the system ground plane;
• and
• a second capacitor set, coupled between the second open terminal of the antenna body and a system ground plane, a control terminal of the second capacitor set being coupled to the control unit, and comprising a third capacitor and a fourth capacitor coupled to the system ground plane;
• wherein capacitances of the first capacitor and the second capacitor in the first capacitor set, and capacitances of the third capacitor and the fourth capacitor in the second capacitor set are smaller than 1 pF;
• wherein the antenna body transceives a first radio frequency signal in the at least one radio frequency signal through a first path between the feed-in terminal and the first open terminal;
• wherein the antenna body further transceives a second radio frequency signal in the at least one radio frequency signal through a second path between the feed-in terminal and the second open terminal;
• and
• wherein a path length of the first path is longer than a path length of the second path, such that such that the tunable antenna is automatically adjusted to different frequencies in accordance with the coupling signal received from the coupler.