Combiner-divider

A combiner-divider comprising:

• a first port;
• a second port;
• a third port;
• a first impedance converter disposed between the first port and the second port;
• a second impedance converter disposed between the first port and the third port;
• and
• an isolation unit disposed between the second port and the third port,
• wherein the isolation unit includes a balun formed of a first semi-rigid cable and a second semi-rigid cable, and terminating resistors,
• each one end of the terminating resistors is connected to the balun, and each of the other ends of the terminating resistors is grounded,
• each line length of the first impedance converter and the second impedance converter corresponds to ¼ wavelength at a center frequency, and
• a relationship of each impedance Ri of the second port and the third port, an impedance Ro of the first port, and each impedance W of the first impedance converter and the second impedance converter is expressed by W=(2×Ri×Ro)1/2.