The Ultrasonic Wind-speed Measurement Based On FPGA

No matter in scientific research, or in industrial production, wind speedmeasurement has a lot of applications, especially in meteorological field and windpower field, velocity measurement has more important value. And compared with thetraditional wind speed measuring instrument for, ultrasonic wind-speed measurementhas many advantages, such as high precision, no mechanical loss, etc. This system isbased on ultrasound in the air the transmission characteristics and design. Ultrasonicthrough the air, will be affected by the influence of air flow in a state or against the windvelocity is different, then the velocity of propagation according to different, cancalculate the influence of ultrasonic wind speeds.The design of hardware circuit in this system and algorithm is the key of this paper,hardware structure of the whole design is the realization of the whole scheme ofultrasonic wind-speed measurement. The pert of hardware circuit design mainly adoptsmodular design, which can be divided into ultrasonic signal sending and receivingcircuit module, information amplification and channel switching circuit module, digitalsignal processing module, RS422interface circuit module.The research of algorithm is based on the improved two-frequency signal theoryalgorithm, calculate ultrasonic signal transmission time, then use spread time tocalculate instant wind speed.Through testing, the system can complete of ultrasonic signal sampling, cansatisfy the design precision calculated the instant wind speeds.