Miniaturized Low Power Ultrasonic Anemometer Based on Cross-correlation
Ultrasonic anemometers are widely acclaimed for their non-rotating parts,rapid response,and high precision in measuring wind speed and direction.However,the traditional ultrasonic anemometers with a large physical footprint,substantial power requirements,and considerable cost impede their extensive utilisation.To overcome these challenges and facilitate the widespread adoption of ultrasonic anemometers,this study presents a cutting-edge design featuring a domestically produced Field Programmable Gate Array(FPGA)integrated with Finite Impulse Response(FIR)filters and cross-correlation detection algorithms.The FPGA-based ultrasonic anemometer design offers clearly noticeable advantages.By reducing the distance between transducers to 80 mm and limiting the sensing region to just 1/10 of traditional ultrasonic anemometers,this compact configuration allows for accurate calibration in some provincial-level wind tunnels.Rigorous wind tunnel tests are conducted to evaluate the performance of the ultrasonic anemometers,demonstrating the instrument's capability to measure wind speed and direction up to 50 times per second.In terms of measurement accuracy,the performance of this ultrasonic anemometer is tested in a wind tunnel,demonstrating its capability to meet specific measurement requirements for both low and high wind speeds.For wind speeds from 0 to 5 m/s,the maximum measurement error remains within±0.3 m/s.In the range of 5 m/s to 20 m/s,the maximum error is ±0.5 m/s.For wind speeds between 20 m/s and 30 m/s,the maximum error is±5%.Under stable wind conditions,the maximum error for wind direction measurement is within±1°.Additionally,the power consumption of the ultrasonic anemometer is significantly reduced to 0.2 W,only 1/20 of the consumption of traditional ultrasonic anemometers with Digital Signal Processors(DSP).The integration of FPGA technology,FIR filters,and cross-correlation detection algorithms into the ultrasonic anemometer design contributes remarkably to improvements in size,cost,and power consumption compared to conventional DSP-based ultrasonic anemometers.The compact size and decreased power requirements make the FPGA-based ultrasonic anemometer an ideal choice for applications necessitating compactness,cost-effectiveness,and energy efficiency.Its potential for widespread utilisation in diverse fields is highly promising.The presented FPGA-based ultrasonic anemometer design surmounts the limitations associated with traditional models.Its compactness,reduced power consumption,and cost-effectiveness make it a compelling solution for accurate wind speed and direction measurements in various practical applications.Comprehensive wind tunnel tests substantiate its precision and reliability,bolstering its potential for widespread adoption and utilisation in diverse fields.
FPGAultrasonic anemometercross-correlationlow power consumption