The Design And Implement Of The Main Control Board Of2D NMR Logging Instrument

Nuclear magnetic resonance (NMR) technology has been widely used in welllogging for oil exploration and in core analysis for petrophysical studies. The currentNMR logging is based on ID NMR technology, only the relaxation information ofpore fluid is measured. When multiple pore fluids, such as oil, gas and water, are present,especially when their signals overlap, the current ID NMR logging technology hassignificant limitations to identify and evaluate them.2D NMR logging use more than oneinformation to make use of the NMR information.The bases of2D NMR logging technology is presented in the second chapter, whichdescribe its methods and applications. Then the idea of sotfware defined radio is used todesign the event control board, the system is implemented mainly by DSP and FPGA andcan complete the signals’ capture and processing, various logging sequences’ generating,communication with the main control board and the self-check function. With minimizethe hardware design, the complicate logging function is completed by the sotfware design.With the deducing of bloch equation, the single hydrogen proton’s behavior is describedin math description. Through the simulation of bloch equation, the echo can be viewedand the reason why NMR logging use CPMG can be explained.And the echo of complicated logging sequence can be predict through the simulation,thus help design the new and advanced logging sequence.Finally, through the hardware experiment, the performance of main control board isproved to achieve the basic requirements of2D NMR logging.