A two‐parameter multifrequency GPS signal simulator for strong equatorial ionospheric scintillation: modeling and parameter characterization

Abstract

This paper presents a physics‐based, multifrequency, strong scintillation simulator that requires only two input parameters: the S4 index and decorrelation time τ0. This simulator is developed based on the two‐component power‐law phase screen model, which is specified by five parameters and suitable for representation of strong equatorial scintillation. By setting three of the model parameters to representative values, numerical mappings from the user input parameter set (S4 and τ0) to the remaining model parameter subset of two parameters can be established through numerical evaluation. The numerical mappings are then used to drive the scintillation model to generate time series of scintillation amplitude and phase. A large group of strong scintillation data (with S4 > 0.6) from two equatorial sites are processed to obtain the representative values of the three model default parameters and to validate the numerical parameter mappings. A MATLAB implementation of the scintillation simulator has been made available.

Statistical Uncertainty in the Frequency Dependence of the Intensity Scintillation Index (S4)

“…(2012) and Xu et al. (2020). Note that we used ideal p and f F values that remain constant throughout the simulation period.…”

“…The goal of this method is to determine an optimal set of phase screen parameters that provide the best fit of the intensity spectrum to the intensity SDF of real scintillation data through an iterative fitting procedure (Carrano et al, 2012(Carrano et al, , 2017Carrano & Rino, 2016;Xu et al, 2020). To facilitate comparison in the same domain, a conversion is applied to transform the intensity SDF I(μ) from the normalized wavenumber domain (in μ) to the temporal frequency domain (in f D ) as follows (Xu et al, 2020):…”

“…where Ф I,model is the intensity SDF in the temporal frequency domain, obtained by converting the power law spectrum of a given set of modeling parameters. The conversion from normalized wavenumber to temporal frequency (i.e., Doppler frequency) is performed as follows (Xu et al, 2020):…”

A Batch Algorithm for GNSS Carrier Phase Cycle Slip Correction

“…To simulate signals containing phase transitions, we use the physics-based phase screen scintillation model described in [44] and [45]. The approach is the same as in our previous work [27] and [25].…”

“…Note that, in general, larger S 4 and smaller τ corresponds to harsh signals containing more cycle slips [27]. These parameters are then mapped to another set of parameters that describes the stochastic structure of the scintillation-inducing medium [45], [27]. This allows us to use the values of S 4 and τ computed from our real scintillation dataset to simulate measurements that are representative of those conditions.…”