【作者】 林海立；

【导师】 王兴奎；

【作者基本信息】 清华大学 ， 水利工程， 2004， 硕士

【摘要】 超声测量仪在工作原理、测量效率,以及对河工模型的影响方面,与传统仪器相比都独具优势。数字信号处理(DSP)方法的引入和实现,将赋予超声测量仪器更好的性能和对复杂测量情况的适应能力。论文从比较国内现有的各种河工模型测量仪器入手,对实现超声测量信号发射和接收的各组成部分进行了说明论证,并根据与数字信号处理算法相匹配的原则确定了开发方案。在仪器中,这个部分完成的工作是:(1)产生一个特定的发射信号;(2)将此发射信号进行必要的放大滤波;(3)使放大滤波后的发射信号激励超声探头发射超声测量信号;(4)接收探头接收回波信号;(5)对回波信号进行放大和滤波等前处理,得到可供后续电路采样的放大信号。另外,这个部分还负责协调测量仪系统的整体运作。在论文里,这部分归结为模拟电路部分。论文的另一大部分是关于数字电路部分的研制开发工作。其开发成果是:(1)对数字信号处理中算法进行了研究,选定了处理回波信号的算法;(2)研制开发了实现数字信号处理(DSP)功能的硬件电路板;(3)规划并完成了计算软件,使电路板可以完成对回波信号的采样、数字滤波、互相关计算等处理工作,并可将计算结果通过串行口输出到计算机。采用模型沙铺就的地形对开发的地形仪进行了实际检验。测试了超声地形仪对不同种类模型底质的适应能力以及对同一沙样的坡面、起伏等地形的测量可靠性,并探讨了浑水条件及水流条件对地形仪工作的影响。各项测试表明,该仪器具有良好的综合性能。更多还原

【Abstract】 Ultrasonic surveying meter is an advanced method in data surveying for river model test. Compared with other kind of devices, it possess principally the advantage of greater work efficiency and less disturbance upon the target being surveyed. The application of Digital Signal Processing (DSP) has greatly enhanced the performance of the Ultrasonic surveying meter and upgraded its adaptability to complicated working conditions.A ultrasonic topographic surveying meter based on DSP has been developed in this dissertation. After comparison of various existing surveying meters for river model test, the design of each component of the ultrasonic topographic meter as well as the circuit scheme based on DSP algorithm matching is presented. The circuit has the function of generating and amplifying a special signal, filtering the noise in it, inputting it to a transducer and making the transducer transmit ultrasonic pulse, receiving and amplifying the echo, and filtering the noise in it. Besides, this circuit coordinates the operation of the whole meter. It is called ultrasonic transmitting and receiving circuit in this dissertation.The development of the DSP circuit including algorithmic software and circuitry hardware is also presented. In this section, the echo signal processing algorithmic is firstly determined by studying the DSP arithmetic and then the DSP circuit is designed. Software is developed to drive the DSP circuit to accomplish functions as signal sampling, digital filtering, cross correlation, and sending results to a computer. A set of actual measurement results of model landform is given. The landform is made up of various model sands in order to test the reliability, stability, and adaptability of the instrument developed. The result shows that performance of the ultrasonic topographic surveying meter is satisfactory.更多还原