Patent ID: 8854276

Claim:
A mobile terminal device, comprising: a first body and a second body that are connected to be capable of transitioning between an opened state and a closed state; a detecting unit that detects the opened state and the closed state; a circuit unit that is disposed in one of the first body or the second body, and includes a ground unit, a power feed unit, and a signal processing unit connected to the ground unit and the power feed unit; a first conductive portion that is disposed in the first body, and is connected to one of the ground unit and the power feed unit of the circuit unit; a second conductive portion that is disposed in the second body, and is connected to the other one of the ground unit and the power feed unit of the circuit unit; an antenna element that is disposed in the first body; an electronic component that is disposed in the second body and has a third conductive portion which is superimposed with the antenna element in the closed state; a switching unit that is configured to be capable of selecting from a first connection state in which the second conductive portion and the third conductive portion are connected at high frequency, and a second connection state in which the second conductive portion and the third conductive portion are cut off at high frequency as compared to the first connection state; a control unit that causes the switching unit to select the first connection state in a case in which the opened state is detected by the detecting unit, and causes the switching unit to select the second connection state in a case in which the closed state is detected by the detecting unit; and a high-frequency cutoff unit including a coil or a capacitor, wherein the second conductive portion and the third conductive portion are connected via the high-frequency cutoff unit in the second connection state.