Patent ID: 9035717
Filing Date: 2015-05-19
Classification: H01P,H03H

Abstract:
1. A balun transformer comprising: an unbalanced terminal to and from which an unbalanced signal is inputted and outputted; a first balanced terminal to and from which a balanced signal is inputted and outputted; a second balanced terminal to and from which the balanced signal is inputted and outputted; a directional coupler that includes a first terminal, a second terminal, a third terminal, and a fourth terminal, the first terminal being connected to the unbalanced terminal, the directional coupler having a predetermined phase difference between an output signal of the second terminal and an output signal of the third terminal, the second terminal being connected to the first terminal by a line that constitutes the directional coupler; a low pass filter that is connected between the second terminal and the first balanced terminal; and a high pass filter that is connected between the third terminal and the second balanced terminal.