Railway satellite channel at Ku band and above: Composite dynamic modeling for the design of fade mitigation techniques

Abstract

SUMMARYPast studies on the railway satellite channel (RSC) at Ku band and above consider exclusively the attenuation coming from the metal power arches (PAs) along the railway route, producing significant though deterministic periodical fast fading. Nevertheless, limited attention has been given to model tropospheric effects on the RSC. The present paper takes a more comprehensive view of the RSC by introducing a novel stochastic dynamic model of rain fading in mobile satellite systems on top of the diffraction because of PAs. The proposed approach builds upon well-established research on rain attenuation time series synthesizers employing stochastic differential equations. It is shown that this propagation tool may provide significant aid, in general, in mobile satellite system simulations and in the design of fade mitigation techniques (FMTs), particularly aiming at the railway scenario. The tool enables the generation of fade events, fade duration statistics, rain attenuation power spectrum and predicting the necessary FMT control loop margin. This is particularly useful for the RSC because most of the proposed FMTs focusing on PAs are not appropriate for compensating atmospheric fading.

Reliable M2M/IoT data delivery from FANETs via satellite

“…The parameters m M O B and σ M O B are calculated through the fitting of a lognormal distribution to the exceedance probability of rain attenuation. Moreover, as also stated in Matricciani and found in Arapoglou et al, the rate of change of attenuation for a moving terminal would equal that of the fixed terminal scaled down by ξ . Therefore, for the dynamic parameters of rain attenuation for mobile and fixed terminal, it holds that where d F I X can be assumed equal to 2·10 −4 s −1 , as also recommended in ITU‐R.P.1853‐1 and found for excess attenuation in Papafragkakis et al…”

“…In Matricciani, the exceedance probability of rain attenuation for a mobile user ( P M O B ) is related to this for a fixed user ( P F I X ) through where ξ is defined as where u M (km/h) is the amplitude of the velocity vector of the mobile terminal, u R (km/h) is the amplitude of the velocity vector of the raincells (advection or front speed), and φ is the angle between these two vectors. Similarly to Maseng and Bakken and Kanellopoulos, in Arapoglou et al, the following stochastic differential equation has been proposed for the generation of rain attenuation time series a M O B ( t ) for mobile terminals: where H ( a M O B , t ) and W ( a M O B , t ) are the drift and diffusion coefficients, respectively, while n ( t ) is an additive white Gaussian noise stochastic process. The coefficients are given by …”

Multiple Gateway Transmit Diversity in Q/V Band Feeder Links

“…The stochastic model of Maseng−Bakken [18], which was adopted as a new Recommendation by the Study Group 3 of the ITU-R in 2009 [19], has been the most popular one. This model is based on the fact that the rain attenuation in dB can be modeled as a first order Gauss Markov process of the Ornestein-Uhlenbeck type described by the following stochastic differential equation (SDE) [18], [20],…”

Statistical Characterization of Adjacent Satellite Interference for Earth Stations on Mobile Platforms Operating at Ku and Ka Bands

“…Similar to [8], we assume that the single path rain attenuation follows the long-term lognormal distribution. Its statistical parameters can be found by a regression fitting procedure on the long-term rain attenuation exceedance probabilitty of a mobile satellite link.…”

“…Ref. [8], following similar footsteps, proposed a static railway satellite channel and extended to the dynamic case by introducing a corresponding time series synthesizer. In the propagation environment considered in the present work, the ESOMP is located in a relatively open propagation environment (without clutter), its directive antenna not picking up any short scale multipath or large scale shadowing.…”