Ionospheric Scintillation study of the low latitude area in China

Weimin Zhen   Jian Feng   Zhongxin Deng   Dun Liu
(China Research Institute of Radiowave Propagation, Qingdao, China, 266107)

Abstract
Ionospheric scintillation effects on satellite signals and ultimately on satellite navigation 
and communication is a growing concern. This concern is primarily due to the challenges that 
ionospheric scintillation may pose on these systems. Ionospheric scintillations occur most 
often in the equatorial region followed by high-latitudes and occur least at mid-latitudes. 
Equatorial scintillations occur within a belt of ±20° either side of the magnetic equator 
and are generally seen during local evening hours. The south of China, under the peak of 
ionosphere anomaly crest region, is one of the areas where scintillation happens frequently 
and makes important effects. This makes it sense to develop the ionospheric scintillation 
studies. For this purpose, a network has been established by CRIRP (China Research Institute 
of Radiowave Propagation) that is used to monitor ionospheric scintillation in low-latitude 
region of China, such as Haikou and Guangzhou, which operates at UHF and L bands. The network 
covers a wide range of latitude and longitude. And a database has been set up for scintillation 
data and TEC data management at CRIRP. Based on the database, some statistic features on 
ionospheric scintillation have been obtained over south of China, we have gained the preliminary 
rules of the scintillation occurrence depending on the geographical location, local time, season 
and the solar cycle. And, using the GPS multi-link signals, we have studied the rules of 
development and movement of the ionospheric irregularities that bring the scintillations.
Moreover, we have calculated the drifting velocity of the irregularities using the cross-
correlation method. Three Ionospheric Scintillation Monitors (ISMs) were installed in Haikou, 
China, the drift velocity of ionospheric irregularities have been deduced though analyzing the 
cross-correlation of scintillation signals. The measured drift velocity shows that 
transmeridional ionospheric drift is east in nighttime, which is consistent with that of DPS-4 
drift observation. The measurement has high precision and temporal resolution. Based on these 
important results, a first ionospheric scintillation now-casting model and preliminary 
forecasting methods have been studied with the help of empirical model and data.More, in order 
to study the ionospheric scintillation in polar region, several GPS monitoring stations were 
constructed at Antarctica Zhongshan and Great-wall stations in 1990’s and in Norway and Finland 
in 2004 by CRIRP. Also, some scintillation features have been studied in polar region.