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第2代数字蜂窝系统已经成熟，在多址方式上主要采用TDMA和CDMA。但是第2代系统采用的窄带CDMA由于受到传输频带窄的限制，未能真正发挥CDMA的特性。因而移动通信系统在经历了第1代模拟系统和第2代2G数字系统之后，正向以宽带CDMA技术为核心的第3代3G数字移动通信系统发
The second generation of digital cellular system has matured, in the multiple access mode mainly uses TDMA and CDMA. However, the narrowband CDMA adopted by the second generation system has not been able to fully play the characteristics of CDMA because of its narrow transmission band. Therefore, after experiencing the first generation analog system and the second generation 2G digital system, the mobile communication system is going to the third generation 3G mobile communication system with wideband CDMA technology as the core