| Coding transmission technology is the key of improving depth of ultrasonic detection and quality of its imaging. With the title “Application of coding transmission technology in high-power detection instrumentsâ€, the thesis systematically researches on the key technology of coding solution ã€signal processing and so on and it is of great academic value and practical significance. Research work is aided financially by National Important Instruments Developing Project(No.2013YQ230575)The major content of the thesis is about application solution of coding transmission technology in ultrasonic detection instrument, designing of Golay coding and excitation module, decoder of echo signal and t esting the imaging result of coding technology by experiment. The main works is as follows:(1) For the requirement of high-power ultrasound detection instruments, the thesis analysed its system architecture and functional requirement of every module, then we raised a overall architecture of coded excitation and analysed feature of different coded mode and choosed the appropriate mode for requirement.(2) The thesis designed appropriate Golay code for high-power detection instruments, raised scheme based on Golay-code, realized the scheme by FPGA, analysed performance parameter of coded excitation, and simulated it by Field II, Modelsim.(3) The thesis designed decoding module of Golay code and simulated by Filed II and Modelsim.(4) The thesis constituted a platform of experiment, choosed suitable briquettes, verified methods of coded excitation and decoding, and analysed the result of experiment.Analysis and result of experiment indicated that we can enhance ultrasound system excitation power indirectly b y using Golay code excitation and compulsing echo pulse in the case of average excitation power is constantly. This methode is useful for detecting material that is hard to penetrate for ultrasound. |
