Ultrasonic Wind Velocity Measurement Based on Phase Discrimination Technique

According to the shortcomings of the existing ultrasonic wind velocity measurement device, for instance, complexity of circuit and difficulty of signal processing, a new ultrasonic wind velocity measurement is put forward based on phase discrimination and a new sensor configuration as well. Thus, a system model is built. Firstly, an equilateral triangle should be constituted by an ultrasonic emission sensor and two ultrasonic receiving sensors. Then by high-precision phase discrimination circuit, the lag between the ultrasonic which is received by two ultrasonic receiving sensors during the traveling time in the upwind and downwind is converted to the phase difference. After that, the wind velocity is measured. Besides, a mathematical model is established among the wind velocity, the ultrasonic velocity, and the structural parameters with ambient temperature. The factors which influence the precision of the wind velocity measurement are analyzed and the solutions are given as well. The experimental results show that in view of the phase discrimination technology, the system has a good numerical stability and the resolution is one order magnitude better than that of the cup anemometer.