超声测距系统的高精度中心椭圆算法

描述了基于新型驱动电路和低噪声程控放大器的超声测距系统.驱动系统的设计从硬件角度提高了回波信号的信噪比和稳定性.基于能量重心校正法和最小二乘法的原理,提出了一种改进型椭圆中心超声回波寻峰算法:通过曲线拟合搜索椭圆中心点,即回波信号能量集中点,进而找到回波信号的峰值点.测试比较证明,与包络线法和三次多项式法相比,此算法测量相对误差稳定在0.2%,适用高精度工业测量.

High-accurate central ellipse algorithm for an ultrasonic ranging system

This paper described a kind of ultrasonic ranging system which employs a new driving circuit and low-noise programmable amplifier. The design of signal-to-noise ratio (SNR) in the circuit was raised to make measurement more stable and reliable. An efficient central ellipse algorithm for estimating the echo peak positions of ultrasonic sampling was presented to find the accurate receive time of echo by searching the peak of energy bursts, which is base on the theories of energy centrobaric correction method and least square method in the ultrasonic ranging system. A comparison of experimental results shows that the proposed algorithm's relative error is approximately 0.2%, which is more accuracy than the envelope detector or the cubic fitted multiple regression equation method, as a result it is suitable for higher accuracy industrial applications.