Abstract:
This article analyses middle and low latitudes (Manzhouli, Chongqing, Kunming and Haikou)
foE data from radio environmental observation network. Consulting other researchers ’ work, we achieve the relationship between the
foE median monthly value and solar activity
F10.7 index and solar zenith angle. The empirical model used in middle and low latitudes of China with the input of F
F10.7 and solar zenith angle is established. The results show that there is a positive correlation between the median monthly value of
foE and
F10.7(correlation coefficient above 0.9), and negative correlation between the median monthly value of
foE 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
foE 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
foE empirical model in China.