Probability density function estimation for characterizing hourly variability of ionospheric total electron content

Abstract

[1] Ionospheric channel characterization is an important task for both HF and satellite communications. The inherent space-time variability of the ionosphere can be observed through total electron content (TEC) that can be obtained using GPS receivers. In this study, within-the-hour variability of the ionosphere over high-latitude, midlatitude, and equatorial regions is investigated by estimating a parametric model for the probability density function (PDF) of GPS-TEC. PDF is a useful tool in defining the statistical structure of communication channels. For this study, a half solar cycle data is collected for 18 GPS stations. Histograms of TEC, corresponding to experimental probability distributions, are used to estimate the parameters of five different PDFs. The best fitting distribution to the TEC data is obtained using the maximum likelihood ratio of the estimated parametric distributions. It is observed that all of the midlatitude stations and most of the high-latitude and equatorial stations are distributed as lognormal. A representative distribution can easily be obtained for stations that are located in midlatitude using solar zenith normalization. The stations located in very high latitudes or in equatorial regions cannot be described using only one PDF distribution. Due to significant seasonal variability, different distributions are required for summer and winter.Citation: Turel, N., and F. Arikan (2010), Probability density function estimation for characterizing hourly variability of ionospheric total electron content, Radio Sci., 45, RS6016,

Estimation of Planar Trend Model Parameters for Midlatitude Ionosphere

“…In Deviren et al (), it has been shown that a midlatitude region of size 10° 20°, in latitude and longitude, respectively, can best be represented by a planar trend. Also, in Turel and Arikan (), the probability density functions of TEC can be optimally categorized when regions of in latitude are considered.…”

Spatio‐temporal interpolation of total electron content using a GPS network

“…[]; Karatay et al . []; Turel and Arikan , []; and Foster and Evans []. Thus, it is an important task to interpolate the missing TEC values within a day or for a whole day.…”

“…The variability of TEC directly reflects the variability in electron density profile, which is a complicated function of position, height, and time. In recent decades, the worldwide, dual-frequency GPS receivers provide a cost-surveying, and monitoring of SW require continuous operation of GPS receivers and uninterrupted TEC estimation for 24 h. The continuous data sets are used in modeling of ionosphere, TEC mapping, computerized ionospheric tomography (CIT), within-the-hour statistical analysis, ionospheric earthquake precursor studies, and prediction of SW events such as those provided in Erturk et al [2009]; Karatay et al [2010]; Turel and Arikan, [2010]; and Foster and Evans [2008]. Thus, it is an important task to interpolate the missing TEC values within a day or for a whole day.…”

Space weather activities of IONOLAB group using TNPGN GPS Network

“…That is the most positively disturbed day in August where Kp and Dst indices for that day indicate that there is a sudden commencement of a geomagnetic storm. The experimental hourly probability density functions (pdf) for some GPS reference station sites are investigated according to the method presented in [5] between 2001 and 2008, and it is been observed that yearly pdf distributions are Weibull distributed for hours that correspond to sunrise and sunset. Other hours are Lognormally distributed.…”