Novel Ultrasonic Beamforming Method Based on Nonlinear Filtering

In this paper a new beamforming method appropriate especially for airborne ultrasonics is presented. The method is based on nonlinear filtering technique called Order Statistic filtering. By exploiting the proposed method we are able to implement ultrasonic range sensing system, for example, for mobile robot applications. The proposed sensing system gives the time-of-flight based distance measure and the angle of incident which is computed by applying the delay difference between sensor array elements. Measures are computed for each detected echo per one transmitted ultra-sonic burst. Besides the robust method to obtain the range and the direction information the presented approach offers also an efficient computation algorithm and hardware solution to exploit it in practice.