Range measurement in underwater range finder using Cross-correlation Algorithm

Range finders are one of the most important devices that are used for controling the height of robots from bottom of the underwater environment to avoid collision with it. In this paper firstly took a simulation processing on received echo signal by using Matlab software. Then made a description about implementation process of the cross-correlation algoritm in FPGA, verified received echo signal and recognition between noise signal and main echo signal is perform by adaptive noise threshold method. The advantages of using this method is to simplify complex processing that previous robots have been used to find the distance between them and sea bottom. This method is also compatible with the change of environment noise and that is one of the considerable point which this paper present.