Method for real-time correcting error of multi-channel high-speed parallel alternative acquisition system

Abstract

The invention discloses a method for real-time correcting error of a multi-channel high-speed parallel alternative acquisition system, which comprises the following steps: in correction, inputting direct current correction signals of different voltages, acquiring a quantization value of each ADC and performing correction point by point to obtain errors point by point and form an error matrix; in measurement, inputting a signal to be measured and performing sampling at time alternating, acquiring quantization values and searching a table in the error matrix, deducting corresponding error value from the quantization values respectively to obtain corrected actual quantization values; and then, rearranging the corrected quantization values according a time phase relationship; converting the rearranged and corrected quantization values into acquisition data for output; and performing low-pass filter; and filtering time-base deviation error spectral line so as to finish the correction of a time error. Compared with the prior art, the method has the advantages that: the deviation and a gain error can be corrected at the same time; and a table searching operation is a corresponding relationship operation of which the process is simple and the calculation amount is small. A low-pass digital filter is very easy to be implemented in a DSP processor and the operation rate is fast so that the efficiency of the time error correction is improved greatly.

Description

technical field [0001] The invention relates to an error correction method, in particular to a real-time error correction method of a multi-channel high-speed parallel alternate acquisition system. Background technique [0002] With the continuous development of electronic information technology, the strong dependence on real-time sampling rate has become the bottleneck problem of modern time domain measuring instruments. The research on analog-to-digital conversion technology (ADC) is restricted by factors such as materials and chip technology, which limits the rapid improvement of its technical indicators. [0003] Under the existing conditions, the use of multi-channel parallel time-alternate sampling structure is still the only way to rapidly increase the real-time sampling rate of the system. The parallel alternate acquisition system uses M-chip ADCs to alternately sample the input analog signals in parallel at the same sampling rate, and the back-end reorganizes the s...

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Problems solved by technology

[0009] Because the two kinds of errors are corrected separately, the operation process of the traditional method is more cumbersome; and the correction of the gain also introduces a large number of multiplication operations, which reduces the efficiency of the correction

[0010] Traditional time error correction methods mainly include sine fitting time base deviation iterative estimation method based on least squares parameter algorithm, decomposition signal algorithm of time base deviation estimation based on signal spectrum analysis, etc. These methods have relatively good correction effects on sampling errors. Excellent, but with a large amount of calculation and complex design, it is difficult to meet the real-time requirements of high-speed acquisition systems

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