Design And Utilization In Cable Detector Based On System Of A Programmable Chip And Time-Frequency-Domain Reflector

The technology of detection cable has been come forth at 1980s,it goes from development to flourish with cable progress. On the one hand,imported physics,electromagnetics and reflection theory,and time-frequency-domain analysis theory into detection cable step by step, it's principal has been changed with each passing day;on the other hand,it's hardware realization has been changed rapidly based on the electronic integration technology. As for market's demand,firstly, function of the cable detector has been changed into both defective detection and maintenance daily, replace of unique defective detection;secondly , signal bandwidth has been changed from DC and baseband to high frequency , even to radio frequency.;thirdly, diversification of cable has been obvious such as long and short , indoor and outdoor , motivity and communication and so on. So has the cable detector ,from two-end to single-end , from single component to small scale, even to super scale integrated circuit; from co-operation by computer to portable, even to handy; from low cost and low precision, high cost and high precision, to high precision and low cost. The cable detector has been changed daily to adapt to market's require.The results show that: for the better market, the cable detector should own its character such as :(1)High precision. on the one hand , judgement the defect types and the defect distance with high precision; on the other hand, judgement the longer the distance and the more defect types. (2)Minisize bulk. micromation is one of the development trends of instruments. Especially, the more and more rapidly does the micro-electronics technology expand on the basis of Nanometer Technologies, so that the Embedded System can function the complex arithmetic and analysis rely on the System of a Chip, on the condition that excellent cable detector is prone to handy. (3) Low cost. not only excellent performance but also low cost is yet important for taking up the market. The lower of cost , the more potential to own market on the condition of the same performance.The properties of the cable detector show it is difficult to utilize three characters at one time, however reasonable using mathematics analysis and micro-electronics technology is possible in achieving the goals. Function procedure is the following: sending a time-limited and frequency-limited signal into the tested cable, at the same time, gaining time center and frequency center of the signal on the basis of time-frequency analysis and Wigner-Ville Distribution (WVD) , then checking the reflection signal rely on a time-frequency crossing relation function, at last judging the defect types and distance by calculating the time excursion and frequency excursion. The entire system is automatic measure, high performance, minisize bulk and low cost founded on the System of a Programmable Chip (SOPC). The time-frequency-domain reflector (TFDR) is abroadly applied to rigorous industry fields, for example, communication, instruments, material-engineering, semiconductor, avigation and so on. In addition, TFDR is also applied to the tradition fields of TDR, such as energy sources reconnoitering, communication net layouts, long-distance reconnoitering etc. TFDR utilizes high performance, minisize bulk and low cost, that accomplishs the development problem of principle and hardware realization on the modern times.