基于FPGA的电话双绞线故障检测算法研究

Research on Fault Detection Algorithm of Telephone Twisted Pair Based on FPGA

为更好满足PC机和MCU的线缆故障检测系统的便携性、即用性和高速传输需求,设计一种便携式电话双绞线故障检测系统。系统以FPGA作为数据处理核心,实现SSTDR中的互相关算法部分。通过分析信号混叠对互相关结果的影响,利用互相关函数的线性性质,从混叠信号背景下提取反射信号,提高故障诊断的准确性。基于FPGA设计信号提取模块,实现对反射信号的提取。设计四单元相乘累加模块的互相关算法核心单元,提升算法效率。实验结果表明,系统的实际表现与符合仿真预期,通过提高信号的采样率将检测误差率降低到1%以下,满足便携式设备的检测需求。

In order to better meet the requirements of portability,usability and high-speed transmission of cable fault detection system for PC and MCU,a twisted pair fault detection system for portable telephone is designed.The system takes FPGA as the core of data processing and realizes the cross-correlation algorithm in SSTDR.By analyzing the influence of signal aliasing on cross-correlation results,and using the linear nature of cross-correlation function,the reflected signal is extracted from the aliasing signal background to improve the accuracy of fault diagnosis.The signal extraction module is designed based on FPGA to extract the reflected signal.The core unit of cross-correlation algorithm of four-unit multiplication and accumulation module is designed to improve the efficiency of the algorithm.The experimental results show that the actual performance of the system meets the simulation expectation,and the detection error rate is reduced to below 1%by increasing the sampling rate of the signal,which meets the detection requirements of portable devices.