US Patent 9851816 Transmitter and controlling method thereof

A transmitter is provided by the present application. The transmitter comprises a first element, configured to receive signal with a first frequency group, wherein first impedance value of the first element is changed according to a force, a second element with a second frequency group, and a tip section, configured to receive outputs of the first and the second elements and to transmit an electric signal, wherein the tip section is used to receive the force.