Research On Cable Anti-theft And Alarm System Based On Sensor Fuse Technology

The theoretical research and application goal of multi-sensor data fusion is to intelligently synthesize information from multiple sources of data and aspects.It produces more accurate, more comprehensive and more reliable description and judgement than a single sensor and it has a wide range of application background in a military and civilian. Multi-sensor data fusion is a hot research field of current technology.Cable theft is one of the most serious disaster in the power system. Recently the frequent incidents of stolen cable caused major economic losses and potential safety problems.It is very important to improve the reliability and timeliness of low voltage power cables anti-theft and alarm system.Low-voltage power line carrier communication has many advantages in power cable anti-theft system. It uses existing physical links, is easy to maintain, easy to promote, easy to use and low-cost. But it shows that power line carrier communication system is very easy to be disturbed though the test of theoretical analysis and practical application.It results in high rate of false positives and seriously lowers the value of the alarm system.We put multi-sensor fusion technology into application of the cable anti-theft alarm system since its superiority in the processing of information. It provides a new way to improve the low-voltage power cables for the safe operation and improve the reliability and maintainability of cable alarm system.The Anti-theft alarm system consists of the host station and circuitry detection terminals. The system uses PLT-232 cable carrier module as a day-to-day inspection work by using spread spectrum carrier module communication technology. The main police station LPC2131 makes a preliminary judgement according to carrier signal's response of the power line terminal module. If the main controller module received carrier signal it proves that the cable are running well.If the carrier communication fails, we use the Hall current sensors to detect the current of line terminal. The current is sent to AD conversion. It shows cable are stolen if the current of line is below the set minimum value after filter process, thus the host station immediately launches CDMA wireless data transmission modules to achieve long-range text messages warning. System maintenance staff could type commands to change or enquirie the control information of the cables anti-theft system at the scene and LCD display module displays operating results and show the circuit current wave of the Hall current sensor at the same time.The thesis explains its basic design ideas and overall plan, introduces implementation of the system's hardware and software. It puts forward some practical anti-jamming measures and carries out the test and analysis.Finally, on the basis of review over the thesis, the future research directions are presented.