A Research On Pipeline MFL Data Sampling And Compression Algorithm

With the enhancement of oil and gas transport status in a country's economy, more attention has been paid on safe running of pipelines. MFL inspection technology is the main method of on-line inspecting long distance oil-gas transportation pipeline. Because of the increasing of the inspection resolution, data precision and detection distance, existing devices can not satisfy the demand of an enormous amount of MFL data in the capability of data storage speed and capacity. Researching on the algorithms suited for MFL data compression and designing high speed MFL data acquisition and compression storage systems have become the key of developing the new generation of MFL inspection devices.FPGA (Field-Programmable Gate Array) is characterized by high speed, high integration level and programmable on line etc, and has very high flexibility and stability. This thesis uses the Spartan II array XS2S100-PQ208 from XILINX corporation. DSP (Digital Signal Processing) is a microprocessor with special structure, providing real time and fast realization of various digital signal processing algorithms. This thesis adopts the TMS320C5509 from TI corporation.In order to enhance system performance, this thesis conducts some research on data sampling and compression. The design is divided into two parts: high speed multi-channel data collection and data compression. As the core of the high speed multi-channel data collection unit, FPGA provides time order to control high speed analogue multiplexers and A/D to sample the multi data which-will be transmitted to data compression unit. As the kernel of data compression unit, DSP compresses the real-time data using one order embedded zero-tree coding. This algorithm can process these data rapidly, and be realized on DSP which can be stopped at any moment.Through lots of experiments, the process of data collection and compression can satisfy the time requirement and decompressed data can replace the raw data for storage.