The ICO system was designed to provide global mobile communications with hand-held terminals. The system had a high degree of compatibility with GSM to provide dual cellular and satellite modes mobile services for the users. Unfortunately the project was scrapped in 2000 because the rapid growth of the cellular systems was expected to take most of the intended market. Today, the cellular systems have grown so much that the market is already saturated in many countries. The growth of the cellular market was made possible by adoption of small cells, which enabled the miniaturization of user terminals and higher frequency reuses at the cost of more complex communication controls. Thus further expansion of the services areas to sparsely populated but vast regions is very difficult with the conventional technology. It seems to the author that the ICO system has a new market potential to further expand the coverage areas and the services for mobile communication. The New ICO, herein proposed has a few features; (1) The CDMA scheme extremely simplifies the communication controls compared with TDMA/FDMA adopted in the Old ICO, (2) The 10 satellites ICO system can enhance the GPS readily by broadcasting a GPS compatible signal for each beam, (3) Dual cellular and satellite mobile system is easily realized for the next generation cellular systems. Another important feature of the proposed system is that most of the system design, Satellite Access Nodes (SAN) earth stations and satellites designs can be reused so the development cost and time can be significantly reduced. The New ICO system can make effective use of the Old ICO, the cellular and GPS technologies to realize a universal mobile communications services for the 21st century.
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