无线技术使得发展中国家能快速地为适应21世纪的要求改进他们现有的电话网络。无线本地环路(WLL)系统使用无线技术提供可靠的、灵活的和经济的本地电话服务,以取代传统的铜钱环路。WLL有时被称为“固定蜂窝系统”。 从服务提供者的角度来看,WLL的最重要的好处是投资成本低,网络扩容十分迅速,以及较低的维护费用和丰厚的补偿。另外,在建立一个WLL系统的过程中不需要知道用户的精确位置,这样就为系统的规划和部署增加了灵活性。已经证明WLL网络有能力在灾 Wireless technologies enable developing countries to quickly adapt their existing telephone networks to meet the requirements of the 21st century. Wireless Local Loop (WLL) systems use wireless technology to provide reliable, flexible and affordable local phone services to replace traditional copper money loops. WLL is sometimes referred to as “fixed cellular system.” From the service provider’s perspective, the most important benefits of WLLs are low investment costs, rapid network expansion, lower maintenance costs and generous compensation. In addition, there is no need to know the exact location of the user in establishing a WLL system, which adds flexibility to the planning and deployment of the system. It has been demonstrated that WLL networks are capable of disaster