Intermodulation test method and device

Abstract

The present invention provides an intermodulation test method and device. The method comprises the steps of controlling a plurality of modulation signal sources to send the broadband modulation signals of different frequencies respectively; adjusting the output signal amplitudes of the modulation signal sources to enable the amplitudes to be the preset values when the signals arrive at the entrances of the tested devices; setting an analysis frequency range of a signal analyzer, and obtaining the intermodulation products generated by the tested devices after the plurality of modulation signal sources output signals to the tested devices; measuring the intermodulation products, and comparing the measurement results with a first threshold value; according to the comparison results, determining whether the intermodulation performances of the tested devices are qualified.

Description

technical field [0001] The invention relates to the field of signal intermodulation interference testing, in particular to a method and device for intermodulation testing. Background technique [0002] Intermodulation (also known as intermodulation) signals are a common disturbance in radio frequency systems and are generated by nonlinear circuits in the transmission channel. When two or more signals of different frequencies are input into a nonlinear circuit, due to the action of nonlinear devices, many harmonics and combined frequency components with frequencies different from the input signals will be generated. The frequencies of these signals are linear combinations of the frequencies of the input signals, which may affect the normal operation of the system. For example, in a communication system, if some of these signals fall within the frequency band of the received signal and are transmitted to the receiving end through certain equipment or devices, it will interfer...

AI Technical Summary

Problems solved by technology

Since the traditional intermodulation test method only uses two carriers for testing, such problems cannot be found

[0013] 2. Scenarios where broadband signals cannot be tested

Due to the use of single-tone signals for measurement, traditional test methods cannot test the working status of the device under test under the influence of intermodulation products with a certain peak-to-average ratio

[0014] 3. Poor ergodicity

Because in the traditional test scheme, one of the two carriers used in the test is fixed at the lowest point or the highest point of the transmitting frequency band, the situation that the two frequency points are in the middle of the frequency band has not been verified during the test

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