Method and apparatus for measuring transmission characteristic of a test object

摘要

Cross-talk attenuation characteristics and/or other transmission characteristics are measured by means of a method which applies a test pulse to the input of an object under test, the test pulse being composed of a plurality of component frequencies having predetermined amplitudes and initial phase angles, with the output of the test object being evaluated by means of Fourier analysis, using an FFT processor. The effective noise is substantially reduced by transmitting plural test pulses, and calculating the mean value of plural results produced sequentially by the FFT processor. Alternatively, the effective noise is reduced by reducing the widths of the effective pass bands of the evaluation by carrying on the evaluation over a period which exceeds the period of a single test pulse, or by setting the amplitudes of some components of the test pulse to zero and increasing the amplitudes of the remaining components.