宽带CDMA与窄带CDMA同时并进

CDMA Moves Forward,Both Narrowband and Wideband

时至今日,窄带IS-95CDMA作为一种可行的无线接口已被许多无线运营者接受.而更多的人已经开始用3到4年的时间来实现应用宽带CDMA的第三代移动通信.过去10年中,TDMA和CDMA作为空中接口的选择方案,一直是无线通信业开发的核心.从80年代末到90年代中期,TDMA系统发展到了顶峰,其中最引人注目的是基于TDMA技术的GSM的飞速发展.

A number of operators have now accepted narrowband IS-95 CDMA as a viable radio interface. A lot more look set to give their backing to wideband CDMA solutions for Third Generation systems in three to four years time.The rival merits of TDMA and CDMA as air interface alternatives have been at the heart of the wireless communications industry's development over the last ten years. From the late 1980s until the middle of the nineties, TDMA systems held pole position, most notably through the meteoric rise of TDMA-based GSM.Across much of the industry it was felt that CDMA was a highly promising solution but that more development work was required to sevure significant benefits above and beyond those achievable via TDMA based systems. In the last couple of years. however, the world's first CDMA systems have gone live, based on the narrowband IS-95 standard developed by Qualcomm in the United States. It may have taken some time to get here but there can be no doubt that IS-95 CDMA now has a significant presence in North America and Asia Pacific.