Sinusoidal signal four parameters testing method and virtual apparatus signal detection device

Abstract

The present invention relates to a sine signal four parameters detection method and a virtual instrument signal detection device. The device consists of a signal modulating unit, a data acquisition unit, a microcomputer and a signal processing unit. The signal generated by a sensor and a signal source is modulated. An analog sine signal is sampled and quantized into a digital signal by a data acquisition card. The digital signal is sent to a computer via a data interface. With the signal detection method of the present invention, FFT conversion is carried out for two continuously sampled signal series respectively. The spectrum peak values of the direct current amount and the alternating current amount of the signal are respectively extracted with the application of the frequency-selecting property of the FFT. With precise phase correction and frequency correction, the amplitude, the frequency, the phase (difference) and the direct current component parameter of the sine signal are accurately measured. Afterwards, the signal wave pattern, the spectrogram and the measuring result are outputted via a display. The dynamic measuring result is preserved to be a data document.

Description

1. Technical field [0001] The invention relates to a four-parameter detection method of a sinusoidal signal and a virtual instrument signal detection device, in particular to a method for measuring the amplitude, frequency, phase (difference) and DC component of a sinusoidal signal with high precision, and a virtual instrument signal A detection device belongs to the field of digital signal processing and analysis. 2. Background technology [0002] In industrial fields such as sensor signal detection and analysis, electrical measurement and power system monitoring, it is often necessary to perform high-precision measurement of various parameters of sinusoidal signals. [0003] Sine signal measurement methods are generally divided into analog measurement and digital measurement. The traditional analog measurement method is mainly realized by hardware circuit, and its measurement accuracy mainly depends on the performance of the measurement circuit. Digital measurement, also...

AI Technical Summary

Problems solved by technology

But it has the following disadvantages: First, due to the adoption of the zero-crossing detection method, the measurement error is large and the anti-interference ability is poor when the signal has zero drift and is interfered by random noise.

Second, since the measurement result is obtained by counting pulses, the measurement accuracy is limited by the accuracy and frequency of the clock

Third, since all are implemented by hardware, it is inevitable to introduce new interference in the measurement process

Third, neither of them gives the detection method of the DC component in the sinusoidal signal

[0013] 2. The main problems of traditional signal detection devices

Therefore, the measurement accuracy is low and cannot meet the increasingly high accuracy requirements in the industrial field

[0016] (2) The hardware cost of traditional testing instruments is high, especially the cost of multi-channel measuring instruments is very high

[0017] (3) Traditional detection instruments cannot realize automatic detection, do not have the function of saving waveform data and measurement result data, and cannot measure all parameters of sinusoidal signals at the same time

[0018] (4) The performance of traditional measuring instruments mainly depends on the performance of hardware, so the adaptability to signals is poor

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