Design Of Data Transmission And Control System For Logging System

Logging system has long adopted seven-core cable for signal transmission, thus resulting in such issues as low transmission rate, low information, signal attenuation and significant distortion. Even if the newest data compression technique and driver circuit of superior transmission performance are applied, data transmission rate can only be improved to 500 kbps. Especially in ultra deep well, signal attenuation and mutual interference of diverse signals become even serious. Thus, cable transmission has become a bottleneck of modern logging data acquisition system.It is presented in the thesis a new logging system based on IOT (Internet Of Things), Ethernet technology, and CAN bus technology. Overall plan of logging system in proposed in the thesis. The system consists of such three components as a logging data monitoring center, a ground-based data transmission relay system, and a logging detection system, with the emphasis on design and implementation of data transmission and control system. The thesis has designed the architecture of data transmission board according to a detailed analysis on its functional requirements. Based on the microprocessor of ARM7TDMI-LPC2292, it is accomplished the design of hardware circuit of logging data transmission system, CAN bus interface circuit for communication with data acquisition subsystem, and Ethernet interface circuit for communication with ground-based PC.μC/OS-II, a real-time operating system has been successfully transplanted to LPC2292. Software design of the system has been achieved, including CAN communication transmit-receive subroutine, driver for network controller chip-CS8900A, and communication program for TCP/IP Application Layer.Hardware and software debug results show that data transmission board of the system operates stably, and data transmission rate reaches as high as 10Mbps. Therefore, the system meets the requirements of modern logging data acquisition system.