Digital oscilloscope with variable-order digital filter

Abstract

The invention discloses a digital oscilloscope with a variable-order digital filter. The digital oscilloscope comprises an input module and a control processing module with an external memory, and also comprises the variable-order digital filter, wherein the input module and the variable-order digital filter are connected with the control processing module respectively; the input module is used for generating a configuration indication; and the control processing module is used for generating a corresponding filter coefficient according to the configuration indication and outputting the filter coefficient to the variable-order digital filter. By using the variable-order digital filter in the digital oscilloscope, the digital oscilloscope can perform digital filter operation without a special computer so as to greatly facilitate site testing and other applications.

Description

technical field [0001] The invention relates to a digital oscilloscope with a variable-order digital filter, belonging to the technical field of electromagnetic measuring instruments. Background technique [0002] A filter is a signal processing device that performs waveform processing on the input signal to filter out unnecessary signals and retain the required signals. According to the nature of the processed signal, the filter can be divided into two types: analog filter and digital filter. Among them, due to the development of computer technology and large-scale integrated circuit technology, digital filters can be realized by computer software, and can also be realized by large-scale digital hardware circuits. Digital filters have the advantages of high precision, high reliability, controllability, and easy implementation. Therefore, digital filters are very important components in digital signal processing systems. In addition, the filter can be divided into four typ...

AI Technical Summary

Problems solved by technology

[0008] For an oscilloscope with a non-adjustable digital filter, it may not be possible to clearly display the signal in some environments with complex interference signals

For example, if the input signal is mixed with low-frequency interference noise, then a low-pass filter such as bandwidth limitation or FilterVU will obviously not work.

[0009] In addition, although the digital oscilloscopes of Agilent and Tek provide extended calculation software that can be used for digital filter calculation on the computer, these software occupy a large amount of resources and can only be run on the computer.

However, in the field test, it is not convenient to carry the computer with you

[0010] It is easy to complete the work of digital filtering through software on a computer, but once this algorithm is transplanted into a chip like DSP, and when the DSP is also responsible for other control and calculation tasks of the digital oscilloscope, it is used for digital filtering calculation The DSP resources occupied are very large, which usually causes the entire oscilloscope to run slower

[0011] Now the test signals are more diverse, the test environment is more complex, and the signal quality will also be affected. How to remove the interference from the complicated signals and find the required signal is a difficult problem for the development of the oscilloscope industry.

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