Modem Navigation System

Earlier days navigation for ship, air and ground used to be undertaken by various instruments eg, Decca, Decca fix, Loran, Shoran, radar, radio-telephone etc to name a few. Fore the last almost 3-4 decades navigation is managed by most modem system using latest technology and techniques. The communication satellites contribute a major support in this venture. Some of the modem navigation systems are described in the following paragraphs.