Finally, there's the Satellite Speed Log, an instrument that uses satellites to measure a ship's speed. The shipboard receiver determines the position and speed of the ship in real time by receiving a Global Positioning System (GPS) satellite signal. The system is characterized by high precision, high reliability and high adaptability, enabling navigation monitoring and navigation functions on a global scale. In addition, Satellite Speed Log provides high-precision time and location records that provide critical data for tracking disaster events such as marine litter or oil spills.