摘要
在高速铁路场景下,列车时速最高可达到350 km/h,留给扇区间切换的时间很短。通过对普速、高速、高铁三种场景下码分多址(CDMA)系统切换时长进行比较研究,得出:软切换、更软切换时长随着移动台移动速度的增加有所变长;切换加比切换去所用的切换时长要长;从软切换和更软切换时长的分析来看,建议采用400 ms作为软切换时长的参考值,而350 ms作为更软切换时长的参考值。最后,提出高铁场景下小区重叠覆盖区域大小的建议。
Under the high-speed railway situation,the highest speed of the train could reach 350 km/h,leaving a short time for the sector switch.The comparison and study of switching time for CDMA system under the situations of ordinary speed,high speed and high-speed railway indicates that the switching time of soft handoff or softer handoff would become longer with the increase of movement speed by the mobile station,and the switching time of switching plus would become longer than that of switching minus.Based on analysis of the switching time in soft handoff and softer handoff,it is suggested that 400 milliseconds should be taken as the reference value for soft handoff time,while 350 milliseconds for softer handoff time.Finally the size of cell overlap coverage area under high-speed railway situation is suggested.
出处
《通信技术》
2011年第6期97-99,共3页
Communications Technology
关键词
移动通信
高铁
码分多址
切换
mobile communication
high-speed railway
CDMA
switch
