Research On Communication Cable Safety Detection Syste

Twisted pair cable communication is the most common wired communication method,commonly used for short-range audio and video transmission,as well as long-distance digital signal and high-frequency carrier transmission.In addition,twisted pair cables also play a crucial role in other industries.For example,in the joint communication of ships,twisted pair cables are often used to complete data connections between multiple ship communication equipment;In the aviation industry,twisted pair cables are also commonly used for transmission between systems or between systems and equipment.Currently,the laying method of twisted pair cables is mainly internal routing,mainly underground routing outdoors,and mostly wall routing and ceiling routing indoors.Traditional cable routine maintenance and troubleshooting methods have problems such as low efficiency and high cost.This paper mainly studies a fault detection system for twisted pair telephone based on spread spectrum time domain reflection method.The system adopts a single ended online detection method,which can quickly locate the fault location and determine the type of fault,and still achieve good detection results in environments with low signal-to-noise ratio.The research content mainly includes:1.Studied the relevant theoretical knowledge of spread spectrum time domain reflection(SSTDR),the causes and types of cable faults,and based on the relevant knowledge of SSTDR and the transmission theory of traveling waves in cables,established a twisted-pair cable fault simulation model through Simulink,verified and analyzed the relevant theoretical knowledge of SSTDR,and conducted a detailed simulation verification analysis of open circuit,short circuit,and intermediate line connection faults.Through simulation data,it was concluded that,The twisted-pair cable fault simulation model can accurately locate the fault distance and accurately determine the fault distance.2.Design a fault detection hardware circuit based on FPGA and draw a PCB,including a signal sending module,a signal receiving module,a power supply module,and a system protection module.For the application of SSTDR in the system,complete the logic circuit design,including signal transceiver,processing,and SSTDR algorithm design.The logic design is simulated and verified.3.The designed system is mounted on a twisted pair of telephones to test the functions of each module and to test three types of faults: open circuit,short circuit,and parallel line.Combining experimental data and theoretical analysis,the feasibility of the SSTDR method is verified.According to the measured results,each module of the system can work normally,and the error in detecting short circuit,open circuit,and intermediate line connection faults is within 1%-5% using the appropriate frequency test signal.The experimental results show that the detection system designed in this paper meets the design requirements,can accurately calculate the fault distance and can identify the fault type.