The Echosounder Calibration System is designed to ensure the highest accuracy for depth measurement instruments in hydrographic and maritime applications. It integrates components such as a sound-velocity sensor, an electronic level, an RTK GPS receiver, and a signal-processing unit, along with specialized BTMS software, to conduct real-world testing, data analysis, and standardized reporting. The system is rugged, precise, and fully compliant with international standards, making it ideal for calibrating single-beam and multibeam echosounders under field conditions.