Iranian scientists at Amir Kabir University of Technology have invented a Global Positioning System (GPS) which detects starts instead of using satellites. "The positioning system can be considered as a substitute for the GPS as it works through detecting stars," Meysam Izadmehr, an Iranian researcher at Amir Kabir University, told FNA on Sunday. "The system is composed of a camera for photography, digital inclinometer circuit and a computer," he added. Izadmehr said that the new GPS can take photos under any kind of condition, including in highly lit or highly polluted areas. Also earlier, the Iranian Defense Ministry unveiled a home-made Land-Based Positioning System with applications in different military, aviation and navigation industries. “Positioning is one of the principles of military operation in the air, on land and on the sea,” Defense Minister Brigadier General Hossein Dehqan said, addressing the ceremony held at Tehran's Malek Ashtar University in December to mark unveiling the system. He underlined that positioning has also applications in non-military fields, including road and rail transportation, aviation, navigation, construction and mapping. Elaborating on the performance of the Land-Based Positioning System, Dehqan said, “Using this method, the positioning signals are transmitted through radio transmitting stations located on land and those interested will find their position with some levels of accuracy by receiving radio signals.” “The Land-Based Positioning System is formed of numerous subsystems and technologies, including powerful transmitters, antennas, and mechanisms for concurrent transmission (both send and receive) at the speed of nano-seconds,” he added. Based on the remarks by the Iranian defense minister, the Land-Based Positioning System is completely different with the GPS which is a space-based satellite navigation system. The GPS provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. The system provides critical capabilities to military, civil and commercial users around the world. It is maintained by the US government and is freely accessible to anyone with a GPS receiver.