Design And Implementation Of Parameter Calibration Library For Signal Generator

The signal generator is a basic electronic measuring instrument widely used at present,and the accuracy of its output signal will directly affect the measurement result.As an important guarantee method of instrument accuracy,calibration technology has become an important link in the development process of most signal generators.Most of the research and development of signal generators in my country now require R&D personnel to design their own calibration modules,the calibration work lacks generalpurpose software,and the calibration results are uneven.This paper designs a general signal generator parameter calibration library to help R&D personnel to complete the calibration.The parameter calibration library provides several external interface functions for the instrument driver to use.Calibration can be completed by passing in a calibration file in a specific format.This design is of great significance to improve the calibration efficiency,ensure the calibration effect and shorten the instrument development cycle.The main content of this article is divided into the following parts:1)Research on calibration method and design analysis of calibration libraryThe first part introduces common calibration methods and principles,analyzes the correction requirements of the signal generator,and selects and improves the calibration method suitable for this design.Related design of parameter dependence.Aiming at the characteristics that the parameters of the signal generator to be calibrated are highly correlated in hardware and complicated dependencies,the concept of parameter dependence and related design are introduced.Then,the overall structure of the calibration system and the design of the calibration process will be described.Finally,the design of the calibration library is analyzed to clarify the role of the calibration library and the key and difficult points in the design.2)Design and implementation of calibration files and calibration library functionsThe second part analyzes the characteristics of the signal generator parameters in the calibration process,and analyzes the parameter-dependent acquisition method.Afterwards,the related design due to the introduction of parameter dependence will be introduced,including the description method of the dependency relationship through the parameter dependence graph and the method of obtaining the correction sequence and updating sequence of the parameters through topological sorting.Finally,a calibration function fitting method combining parameter dependence and piecewise fitting is introduced to enable parameter dependent design to participate in the specific calibration implementation process,ensuring the accuracy of calibration.3)Design and implementation of calibration files and calibration library functionsThe third part combines the calibration system and calibration process design to divide the calibration library function.The type selection and format design of the calibration file responsible for transferring the correction information are carried out.The design of the interface function of the calibration library is explained in combination with the content of the calibration file and the previously improved calibration method.After testing and verification,the signal generator parameter calibration library designed in this paper has a sound function and can complete the calibration of the signal generator's parameters to be calibrated,which greatly reduces the output error and meets the index requirements.At the same time,two different types of signal generators were tested,and both achieved significant calibration effects,indicating that the calibration library is general.