基于m序列的无串扰超声波测距系统

No crosstalk ultrasonic ranging system based on m sequence

超声波测距是机器人较为常用的避障方法,但是当多个超声波测距系统同时使用时容易产生串扰的问题。将伪随机码m序列应用在超声波测距系统中,为发射的每一路超声波进行编码,使得发射端所发射的超声波具有可识别性。回波中的编码与本地所发射的超声波编码进行自相关运算,利用m序列良好的自相关特性,判断此回波是有效回波还是干扰回波。系统能有效地识别干扰回波并将其舍弃,从而避免多个超声波测距系统之间发生串扰。实验结果表明,该系统的测距误差小于1.9%。

Ultrasonic ranging is robot obstacle avoidance methods,but when mul-tiple ultrasonic ranging system used at the same time easy to produce crosstalk problems.Apply pseudo random code m sequence in the ultrasonic ranging system,each for launch ultrasonic encode all the way,make the ultrasonic wave can b-e emitted by transmitting terminal identification.The launch of the ultrasoni-c echo of coding and local autocorrelation arithmetic coding,using m-sequence good autocorrelation characteristic,judge the echo is effective echoes or int-erference. System can effectively identify the clutter echo and abandon it,so as to avoid occur crosstalk between multiple ultrasonic ranging system.The ex-perimental results show that the system of ranging error is less than 1.9%.