摘要
研究我国南海地区(北纬0°到25°,东经105°到120°)电离层F层临界频率月中值变化特点及利用人工神经网络预报月中值的技术.文章首先给出这个海区上空F2层临界频率月中值随太阳活动水平、地理纬度、季节和昼夜变化规律.结果指出电离层临界频率随纬度分布除出现驼峰现象外,在4和10月份还存在大范围的电离层气泡区域。在这个区域电离层密度出现中间稀周围高特点;电离层临界频率的分形分析得到其相关维为2.7。其次,我们选用5个因子作为网络输入,用电离层观测资料训练网络,建立了我国南海地区电离层模式。利用这个模式预测的电离层临界频率与实际测量的符合较好,可以满足应用要求。
In this paper, the ionospheric monthly average characteristics of the F region in the mouth China Sea (including from 0°-25°N, 105°-120°E)are studied. A regional ionospheric model by Artificial Neural Network(ANN) is given. First, variations of the critical frequency with solar active level, latitude, season and diurnal are discussed. Results showed that there is a large hobble area during April and October in this region. From analyses of the ionospheric critical frequency, their correlation dimensions are about 2. 7. Next , five factors are used as the input parameters of this ANN.The comparisons of observed ionosphetic critical frequencies with predicted ones are in very goood agreement.
出处
《电波科学学报》
EI
CSCD
1998年第2期213-218,共6页
Chinese Journal of Radio Science
关键词
电离层预报
人工神经网络
电离层模式
Ionospheric prediction Artificial neural net Ionospheric model