Characteristics Analysis And Frequency Expansion Technology Of Long Cable Channel In Power Line Carrier Communication

Oil well production requires real-time monitoring of down-hole temperature,pressure and flow rate,so that the oil well monitoring personnel fully grasp the down-hole information,monitoring and controlling the production process.More down-hole data transmission method,the power line carrier communication is a kind of better method and has long transmission distance,security high,channel,high reliability,less investment and quick,oilfield synchronized power grid construction has become underground power system widely used communication mode.Firstly,this paper analyzes the background and current status of research on power line carrier communication,construct a simplified power transmission line model,analysis of the power line of the attenuation characteristics and impedance characteristics,noise characteristics,for the power line channel for simulation research.Secondly,the paper analyzes the power line carrier communication technology content,analyzes the power line carrier communication harmonic generation reason and harm,puts forward the use of spread spectrum technology to reduce harmonics,improve the security of data transmission.Then,the paper detailed describes the principle of spread spectrum technology,spread spectrum technology has higher anti-reduction,anti-interference,and constructs the model of spread spectrum communication,to classify the different spread spectrum systems using spread spectrum communication technique can improve the reliability of data transmission.Then,with the down-hole data transmission speed is low demand,based on spread spectrum communication technology,developed a down-hole data transmission system based on power line spread spectrum carrier.The lower computer system can real-time down-hole data acquisition,after the carrier spread spectrum chip modulation will be sent to the power line,receiving end upper computer system can despread and demodulation using spread spectrum carrier chip will be passed to the control machine,through the human-computer interaction interface is sent to the display and display them,to further improve the reliability of the power line carrier communication.