Passive intermodulation distortion measuring method and system

A system for measuring a passive intermodulation signal, which is generated by a device under test in a high frequency band, comprising:

• a plurality of signal generation means for generating a plurality of test signals, each having different frequencies;
• signal separation means including a first terminal, used to input the plurality of test signals from the plurality of signal generation means, a second terminal, used to output the plurality of test signals received at the first terminal and to input the passive intermodulation signal, and a third terminal used to output only the passive intermodulation signal;
• a transmission line having two conductors, one end of which is connected to the second terminal of the signal separation means, and which provides an impedance mismatching condition between a device under test and the transmission line, and generates a standing wave of the plurality of test signals along the transmission line, while the device under test is located between the two conductors along the transmission line where the standing wave is generated, and
• passive intermodulation measurement means connected to the third terminal of the signal separation means to measure the passive intermodulation signal,
• wherein the transmission line is a hollow transmission line, and the other end of the transmission line is open;
• and the device under test is arranged at the position of the anti-node of a current standing wave or a voltage standing wave in the hollow transmission line to measure passive intermodulation.

A method for measuring a passive intermodulation signal, which is generated by a device under test in a high frequency band, comprising the steps of:

• generating, in a high frequency band, a plurality of test signals, each having different frequencies;
• providing an impedance mismatching condition between a device under test and a transmission line to which the plurality of test signals are input, and generating a standing wave of the plurality of test signals along the transmission line;
• and
• measuring the passive intermodulation signal,
• the method further comprising,
• before the method is used, adjusting a length of the transmission line is performed so as to maximize a passive intermodulation signal level that is to be measured in the state wherein the device under test is not connected,
• wherein the step of generating a standing wave includes short-circuiting the tip of the transmission line by the device under test.