Research On The Intelligent Measuring Instrument Based On The Embedded System

House area measuring is a professional measuring technique. The house's plane, elevation structure size and the using area are the basis of house sale, which relate to the state's tax and the people's vital interests. Although the traditional way, which the metering band or steel tape is adopted to measure the house area, can meet the basic requirements, it can only give the basic data and cannot achieve automatic calculation in the large span measurement and high measuring where the comparatively large error and labor intensity exist,.In this paper, the intelligent measuring instrument with embedded technology based on principle of ultrasonic ranging is studied. The intelligent measuring instrument for measuring part of ultrasonic ranging circuit is improved, which is mainly made up of ultrasonic transducer, the circuits of emitting and receiving ultrasonic and signal processing circuits. The double threshold detection principle applied in signal processing circuits. The testing unit can realize the sliding threshold and the pulse width detection and decline the rate of error testing to a certain degree. At the same time, a temperature compensation circuit is designed to measure the ambient temperature in real-time to amend the ultrasonic velocity, thus the accuracy of measurement is greatly improved.TMS320LF2407 as the control core is adopted to achieve data collection, data processing and display. In accordance with the principle of wavelet analysis, the application of wavelet analysis in ultrasonic signal de-noising is simulated by use of MATALB. In addition, an infrared communication interface circuit based IrDA standard is designed to send the data to PC for saving and analyzing.Finally, the control and algorithm modules for DSP are programmed to compensate the data collected by the temperature compensation circuit into the ultrasonic velocity, and the corresponding delay program module is also programmed to improve the accuracy of the measuring apparatus. The experiments and simulations show that the actual request can be satisfied and that the design goal is achieved.