基于Zoom-FFT技术的铁路移频信号检测系统设计

Design of railway frequency shift signal detection system based on Zoom-FFT technology

摘要:

为精准检测轨道移频信号的特征参数值，实现列车通信数据的实时稳定传输，设计基于Zoom-FFT技术的铁路移频信号检测系统。以AD转换电路作为核心电子输出装置，借助DSP移频芯片、信号传感单元对于列车通信数据的聚拢调节作用，在LCD屏幕内生成即时性铁路移频信号显示文件，再联合微处理接收元件，实现对信号特征参量的精准获取，完成检测系统的硬件结构设计。在此基础上根据信号数据的瞬时输出频率，确定标准的模态移频函数，完成基于Zoom-FFT技术的铁路移频信号频率分析。设置数据采集、移频滤波、WIFI通信三类程序型算法，建立信号数据库与核心检测主机间的物理连接，实现系统检测软件及应用主程序建立，结合以上所有软、硬件执行结构，完成基于Zoom-FFT技术的铁路移频信号检测系统设计。对比实验结果显示，应用新型检测系统后，低频、高频轨道移频信号的检测精度均出现明显提升，解决了原有检测系统支持下，列车通信数据实时传输稳定性较差的问题。

Abstract:

In order to accurately detect the characteristic parameter values ??of the track frequency shift signal and realize the real-time and stable transmission of train communication data, a railway frequency shift signal detection system based on Zoom-FFT technology is designed. Using the AD conversion circuit as the core electronic output device, with the aid of the DSP frequency shift chip and the signal sensing unit for the adjustment of the train communication data, an instantaneous railway frequency shift signal display file is generated in the LCD screen, and then the micro-processing receiving element is combined. To achieve accurate acquisition of signal characteristic parameters, complete the hardware structure design of the detection system. On this basis, according to the instantaneous output frequency of the signal data, the standard modal frequency shift function is determined, and the frequency analysis of the railway frequency shift signal based on the Zoom-FFT technology is completed. Set three types of procedural algorithms: data acquisition, frequency shift filtering, and WIFI communication, establish the physical connection between the signal database and the core detection host, realize the establishment of the system detection software and application main program, and combine all the above software and hardware execution structures to complete the Zoom-based -Design of FFT technology railway frequency shift signal detection system. The comparison experiment results show that after applying the new detection system, the detection accuracy of low-frequency and high-frequency track frequency-shifted signals has been significantly improved, which solves the problem of poor stability of real-time transmission of train communication data supported by the original detection system.