早在第二代移动通信技术（ＧＳＭ、 ＣＤＭＡ）方兴未艾之际，国际电联就已紧锣密鼓地制订第三代（３Ｇ）移动通信标准。其中，进展最快的是采用宽带ＣＤＭＡ技术的ＵＭＴＳ系统。其实，正值ＧＳＭ和ＣＤＭＡ充分发展，频谱资源紧张已初见端倪，同时网络概念正以燎原之势席卷股 As early as the second generation of mobile communications technology (GSM, CDMA) in the ascendant, ITU has been in full swing to develop third-generation (3G) mobile communications standard. Among them, the fastest progress is the UMTS system using broadband CDMA technology. In fact, at the full development of GSM and CDMA, spectrum resources have begun to show signs of clues, while the network concept is praising the momentum