This book describes the design features characteristic of LEO satellites, discussed the design of LEO satellite communication network, and presents an analytical framework to evaluate their performance. broad scope of this book, including a new research perspective, the tools necessary, and fundamental analysis techniques, will enable engineers to: identify the advantages and disadvantages of non-geostationary satellites compared with conventional geostationary systems, understand how the LEO satellite system can meet the requirements certain future global PCNs, compare several different schemes have access - and choose, the most promising recent schemes for future wireless communications and mobile satellite systems, determine the traffic characteristics LEO satellites for global PCNs, and applying new techniques to evaluate and improve the performance of LEO satellite systems