中文摘要：

超声传感器不同发射激励对超声发射功率有很大影响，决定了空气超声波探测距离。对超声激励脉冲进行了功率谱分析，给出了不同类型激励脉冲与发射功率之间的关系。设计了远距离超声传感器双极性发射电路，实现了脉冲个数和脉冲频率可调。通过实验研究，确定了超声激励脉冲的类型、个数与激励电压。该电路已成功用于远距离超声波测距系统中，能稳定、可靠地检测25m处的障碍物。

英文摘要：

Different transmission exciting pulses of ultrasonic sensor have great effect on ultrasonic transmission power,and determine ultrasonic wave detection range. The relationship between different kinds of exciting pulse and transmission power is given by analysis of power spectrum. The bipolar transmitter circuit of long-distance ultrasonic sensor is designed to adjust the number and frequency of pulse. The type,number,excitation vohage of ultrasonic exciting pulse are determined via experimental studies. The circuit has been successfully used in long- distance ultrasonic ranging system, and can reliably and stably detect the obstacles with the distance about 25 m.