Preliminary study on ionospheric f_oE empirical model in middle and low latitudes of China

This article analyses middle and low latitudes (Manzhouli, Chongqing, Kunming and Haikou) f_oE data from radio environmental observation network. Consulting other researchers ’ work, we achieve the relationship between the f_oE median monthly value and solar activity F_10.7 index and solar zenith angle. The empirical model used in middle and low latitudes of China with the input of F F_10.7 and solar zenith angle is established. The results show that there is a positive correlation between the median monthly value of f_oE and F_10.7(correlation coefficient above 0.9), and negative correlation between the median monthly value of f_oE and the cosine of solar zenith angle at noon(correlation coefficient above 0.7). Compared with the measured data, it is found that the error standard deviation of the empirical model of f_oE is less than 0.1 MHz and is better than the international reference ionosphere(IRI). This study is of great siginificance to the improvement of IRI model and the establishment of autonomous ionospheric f_oE empirical model in China.