hybrid satellite constellations as Ellipso Borealis and Concordia system. This book is important for modern shipping, truck, train and aeronautical societies because GMSC in the present millennium provides more effective business and trade, with emphasis on safety and commercial communications. Global Mobile Satellite Communications is written to make bridges between potential readers and current GMSC trends, mobile system concepts and network architecture using a simple mode of style with understandable technical information, characteristics, graphicons, illustrations and mathematics equations. Global Mobile Satellite Communications represents telecommunications technique and technology, which can be useful for all technical staff on vessels at sea and rivers, on all types of land vehicles, on planes, on off shore constructions and for everyone possessing satellite communications handset phones.