Software Design Of Large-capacity Waveform Storage And Analysis

With the rapid development of the electronic information industry,signal bandwidth and data volume are increasing,digital oscilloscopes need to have a large storage depth and efficient analysis capability while maintaining a high sampling rate in order to adequately capture and analyse waveform details or episodic signals.This thesis is based on a model of high-performance digital oscilloscope system,Visual Studio2022 as a platform,using C# language to complete the software design of high-capacity waveform storage and analysis.The storage module uses sequential sampling to achieve greater storage depth and flexible storage configuration;The analysis module uses pure software algorithms to design the spectrum analysis and eye diagram measurement functions for high-capacity data,thus meeting the user’s testing needs for analysis of signal spectrum and signal quality.The details of this thesis are as follows:1.Sequential Sampling module: Sequential sampling based on large-capacity segmented storage is achieved through software configuration parameters and segmented reading.The maximum storage depth of a single frame can reach 1Gpts;depending on the time base and storage depth,up to 100 k frames can be stored in segments.At the same time,in order to better observe the large amount of data under sequential sampling,three analysis modes are designed in the IPC interface: single frame,sequential frame and selected frame mode.In the single-frame analysis mode,the time stamp parameters of each frame can be read,so that the important information contained in the absolute timing of each frame can be observed;in the sequential-frame and selected-frame analysis modes,the coordinates of multiple frames of waveform data can be transformed to achieve four waveform display modes: superposition,stacking,splicing and 45° oblique angle,so that users can easily compare waveforms from multiple angles,such as horizontal and vertical.2.Research on spectral analysis improvement algorithm: To address the shortcomings of slow FFT analysis of large-capacity waveforms at the present stage,we study the relevant techniques to improve the efficiency of spectrum analysis,including sparse Fourier SFFT transform,MonoFFT transform based on single-bit quantization and2D-FFT transform.By comparing the performance indexes of the three techniques,the implementation scheme of spectrum analysis is improved from the software algorithm,and the preliminary implementation is carried out on the oscilloscope software platform;the scheme can guarantee the original frequency measurement accuracy under the condition that the maximum number of analysis points can reach 65536 points,which can improve the operation efficiency of spectrum analysis by up to 60%.3.Eye Diagram measurement function module: Based on the deep storage mode of the high-capacity waveform,the waveform data can be acquired in megabytes by a single trigger,thus reducing trigger jitter;the acquired data is recovered by a software phase-locked loop to the signal standard clock,effectively avoiding non-linear errors in the hardware circuit.The construction and plotting of the eye diagram matrix is the responsibility of the system’s data acquisition and processing threads respectively,allowing the user to qualitatively determine the quality of the signal transmission within seconds.In addition,the module allows for the measurement of eight related parameters such as eye height and eye width.In this thesis,the detailed software design and implementation of the above three functional modules are carried out,and it is verified that the test results of each module meet the expectations.