第3代移动通信主流接入选择CDMA方式的理由

Reasons for selecting CDMA as the standard of 3 G mobile communication systems

结合3G当前的研究成果和未来发展的需要,主要从功率利用率和频谱利用率两方面分析比较了CDMA和GSM两类不同移动通信体制的差异,印证了CDMA更胜一筹的原因。文章从对移动信道多径传播能量的利用、发信持续时间内的发信功率和功率谱密度3方面阐述了CDMA为何能保持功率利用率居高不下,而瞬时发射功率小(可减少电磁干扰对人体的危害)的缘由;从CDMA使用扩频通信方式和使相邻小区可复用相同频点等方面的技术,分析了导致CDMA频谱利用率高的直接原因。

Considering the demand of present research and future development of 3 G,the features of CDMA and GSM mobile communication systems are analyzed from power utilizing efficiency and radio spectrum utilizing efficiency. The reasons of selecting CDMA as the only wireless multi-access mode for 3G mobile communication systems are presented. The paper expounds why CDMA can retain high power utilizing efficiency and low instantaneous launch power by analyzing the using of multi-path transmit energy in mobile channels, launch power and power spectrum density in launch duration time. This paper also analyzes the reason of leading CDMA high frequency spectrum utilization by adopting expanding frequency technique and multiplexing the same frequency in nearby area.