摘要
分析比较了位于赤道异常区的桂林和武汉两地观测到的GPS信号闪烁与TEC起伏的统计特征,包括两地闪烁活动随地方时变化特性和空间分布以及闪烁与TEC起伏的关联。统计分析表明:L-波段振幅与相位闪烁活动主要发生在夜间,最大振幅闪烁出现率在午夜及其前后数小时,表现出对地方时的强依赖性;武汉闪烁出现率峰值出现时间平均比桂林滞后约1至2小时;闪烁出现率逐日变化幅度很大,倾向于间歇性出现;两地发生闪烁的空间区域都相对集中于方位偏南、卫星仰角50°以下的区域;伴随振幅闪烁活动及其强度的增强,都出现明显的TEC的耗空和ROT的快速起伏,ROTI指数也明显增强,统计分析得到,两地的S4和ROTI呈显著正相关。
In this paper, a comparison of GPS scintillations and TEC fluctuations observed at Wuhan （114.36°E, 30.53°N, magnetic latitude 19. 4°N） and Guilin （110.33°E, 25. 29°N, magnetic latitude 15.04°N） was presented. The activity of amplitude scintillations mostly occur in the night at two sites and the highest percentage of occurrence appears near midnight with strong dependence of local time, and the frequently occurring time of the scintillation activity at Wuhan lag behind that at Guilin for about 1-2 hours on the average. The day-to-day variation of the scintillation activity is very obvious and inclined to occur intermittently. Spatially, distribution of amplitude scintillations mainly appear in the region with the elevation below about 50° and the azimuth from 180° to 240° for Wuhan and 120° to 240° for Guilin, respectively. For most cases, scintillations always associate with TEC depletion, fluctuation of ROT and distinct accretion of ROTI. The statistic analysis shows there is a remarkable positive correlation between the ROTI index and the S4 index with correlation coefficients of 0.97 and 0.72 for Wuhan and Guilin, respectively.
出处
《电波科学学报》
EI
CSCD
北大核心
2007年第2期181-186,共6页
Chinese Journal of Radio Science
基金
国家自然科学基金项目(40474055)
