Ultrasonic underwater depth measurement

A precise, linear indication of the depth of water in a specific part of the sea is required. This demands a continuous level measurement. There are a wide variety of ways to produce a signal that tracks the depth of water in a specific part of the sea. Ultrasonic detectors find the distance between the seabed and the surface of the water. To measure the level, depth, with an ultrasonic range detector, the module is mounted at the bottom of the sea, seabed, looking up the surface. We must measure the time between the transmit pulse and the echo received pulses. Since the ultrasonic signal is traveling at the speed of sound, the time between transmission and echo received is a measure of the distance to the surface, water depth. A micro-controller sends a pulse to the ultrasonic module. The module transmits an ultrasonic wave for a short period of time and waits to receive its echo. As soon as the echo is received at the ultrasonic module, a pulse is sent to the micro-controller, which measures the time between two pulses. There are two modes of operation, program mode and run mode. When the unit is powered, it is programmed to start up in the run mode, to detect the distance from the transducer face to a target depth in meters. The unit can be placed into program mode at any time by pressing the menu key to alter the value of the parameters in order to better suit the application or user preferences. The unit of measurement, type of measurement, set point of alarms and factory setting are some of its parameters. The working time of the transition and receiver part of the module is specified by the micro-controller normally for each second that ultrasonic pulses are transmitted. The measuring error is approximately 1.25%. Such an error value is acceptable.