Multiplexer

A multiplexer comprising:

• a common terminal, a first input/output terminal, and a second input/output terminal into and from which a high-frequency signal is input/output;
• a first filter circuit having a first frequency band as a pass band and being connected between the common terminal and the first input/output terminal;
• a second filter circuit having a second frequency band, which is different from the first frequency band, as a pass band, and being connected between the common terminal and the second input/output terminal;
• a first cancel circuit including a first elastic wave resonator, a first terminal, a second terminal acoustically connected to the first terminal via the first elastic wave resonator, and a third terminal acoustically connected to the first terminal via the first elastic wave resonator;
• and
• a second cancel circuit including a second elastic wave resonator, a fourth terminal, and a fifth terminal acoustically connected to the fourth terminal via the second elastic wave resonator;
• wherein
• the first terminal is connected to the first input/output terminal, the second terminal is connected to the second input/output terminal without going through the second cancel circuit, the fourth terminal is connected to the third terminal without being acoustically connected to the first cancel circuit and the second cancel circuit, and the fifth terminal is connected to the second input/output terminal;
• and
• the first cancel circuit and the second cancel circuit generate signals that cancel out an unnecessary signal in a prescribed frequency band propagating between the first input/output terminal and the second input/output terminal.