The Ground Wind System Research And Design Based On Fpga

The wind is one of the elements of the most active in meteorological factors and the impact is all pervasive from military, meteorology, scientific experiments, industry, navigation, aviation and other fields, therefore wind velocity and direction measurement is particularly important.This paper propose the time difference method measuring wind speed and direction because of the lack of traditional measuring wind speed and direction, this method eliminate the affection of temperature, and we design a hardware system consisting of Field-Programmable Gate Array(FPGA) and Microprocessor ATmega128.In the part of analog circuit designing, the paper designed the ultrasonic sensor drive circuit and the sinal processing circuit at receiving terminal. The low-voltage driving circuit is designed, so as to make work reliable and stable. For receiving stable and accurate ultrasonic signals, we did elaborate design ultrasonic receiver circuit and signal processing circuit, the ultrasound signal after pream plification circuit and signal separation filter circuit is as the input of automatic Gain Control (AGC) circuit, it ensures the amplitude of ultrasound sinusoidal signal voltage inside a stable range, this greatly improves the accuracy of time measurement results.For digital circuit part, according to the characteristics of FPGA, it integrated with most digital circuit, including the ultrasonic generator module, the high-speed acquisition and timer module, the data management module, the communication module, etc. This structure and idea has mostly narrowed down the design of hardware, has higher integration, improves the system’s reliability and stability, in addition, it will contribute to system upgrade. ATmega128is mainly in charge of transforming and calculating the data of the count value from FPGA and finally arrive at the wind speed and direction, moreover, through the CAN bus communicating with the host computer.After system apparatus is manufactured and debugged, we test it’s precision at the CMA Meteorological Observation Centre, the detection accuracy is in compliance with requirements in this paper. Finally, we conduct the EMC test at the institute of14of China Electronics Technology Group Corporation and it has met the quality specification.