| 摘要 |
PROBLEM TO BE SOLVED: To determine a filter for equalizing an analog signal path included in a measuring instrument that simultaneously measures a plurality of signals of a plurality of frequencies in one band, using magnitude measurement data for high frequency bands for which phase-calibrated signal sources are not readily available. SOLUTION: A sinusoidal signal source together with an accurate power meter is used to provide a stepped frequency input over a desired frequency band to an analog signal path with an accurate measured magnitude. The output signal of the analog signal path is digitized and the resulting frequency magnitudes are computed. Then, the resulting power meter results are deducted from the frequency magnitudes measured each time by the measuring instrument to determine the magnitude response of the analog signal path. Using a Hilbert transform, the corresponding phase response is determined based on a minimum phase assumption over the desired frequency band. From the magnitude and phase responses, an inverse or digital equalization filter may be designed for equalizing the analog signal path. COPYRIGHT: (C)2007,JPO&INPIT
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