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In the ultrasonic gas temperature measurement system, the principle is that the velocity of sound in gas is a function of temperature. But because the propagation speed of ultrasonic wave can be easily affected by humidity, the accuracy of the gas temperature measurement will be affected too. This dissertation will implement the ultrasonic gas temperature measurement system with humidity correction suitable for all kinds of environment humidity. This type of ultrasonic technique is a highly efficient algorithm with the advantages of both time-of-flight method and phase shift method. And the system is realized with a single-chip microcomputer-based with a relative humidity/water vapor pressure meter. The main advantages of this ultrasonic temperature measurement system are high resolution, using narrow-bandwidth ultrasonic transducer of low cost and ease of implementation.

X-ray Pipe Crawler is the welding seam detection device that widely used in Oil pipeline construction of middle and far distance transmission. In this paper, a method of automatic positioning system used in pipe crawler weld by using DSP is introduced. And investigate the base method of seam image process. The design of an automatic positioning system used in pipe crawler weld based on TMS320DM642 is given. The image edge detection simulation system experiments are based on MATLAB.

A novel circularly polarized array designed for millimeter wave digital radar module was proposed and validated in this paper. The circularly polarized array was designed with single feeding point for easily integrating with front-end module. A new kind of medium filled circular cavity was employed as transition to connect the output of the T/R module and the feeding point of the array. T M 010 mode was selected as the operating mode of the circular cavity based transition for its special field distribution. Good performance of flexibility, return-loss, axial ratio and radiation pattern were observed.