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Due to the development of high throughput satellites, the multicarrier mode operation of high power amplifiers in the satellite transponders is nowadays a growing trend. This tendency poses new challenges in the design of algorithms able to mitigate the impairments induced by the nonlinear behavior of such amplifiers. One of these challenges is the construction of an accurate low complexity model...
In a recently published paper, a novel ap-proach for blind feedback synchronization of the symbol tim-ing has been proposed. In order to avoid any jitter floor irre-spective of the selected modulation scheme, a filter with very particular properties has been developed and placed in par-allel to the receiver matched filter. Nevertheless, the jitter performance of this method degrades in case the carrier...
Aggressive frequency reuse is being considered for multibeam satellites to achieve higher system capacity using available spectrum. Towards achieving the ideal gains of such a reuse, precoding techniques are being considered to minimize the resulting co-channel interference. Most of the precoding techniques, however, do not explicitly consider the distortions introduced by the high power amplifier...
Employing high order constellations is inevitable in order to achieve higher spectral efficiency in satellite communi- cation systems. In DVB-S2X standard, constellations with up to 256 points have been included. However, optimizing such high order constellations is a difficult task. In this paper we propose a very simple constellation design based on the radial map from QAM constellations to non-uniform...
The Next Generation Regenerative On Board Processor (NGROBP) is an ESA sponsored program led by Space Engineering. The activity objectives are to investigate the next generation of satellite OBP hosted payloads for high speed security and institutional applications and propose a technology roadmap for eventual payload development. The study involves the development and validation in a laboratory environment...
This paper summarizes the outcome of a study aimed at analyzing the benefits and hence the potential role of On-Ground BeamForming (OGBF) techniques in future satellite systems. To this end the study analyzed different scenarios where OGBF could find applications to assess if use of such techniques can provide advantages in terms of system performances and costs. Given the impact of ground beamforming...
We describe the experiment that was carried out to communicate a Mobile Platform and a Ground Station through a Medium Earth Orbit (MEO) satellite. The physical layer in both ends, based on the specifications of the Satellite Component of the Universal Mobile Telecommunications System (S-UMTS), was implemented using Software Defined Radio (SDR) technology. The Mobile Terminal was boarded in both an...
Intentional and unintentional interferences are an increasing threat for the satellite communications industry. In this paper, we aim to localize an interference with unknown location using frequency of arrival (FoA) technique by only relying on the measurements obtained through a single satellite. In each time instance, the satellite samples the interference and forwards it to the gateway to estimate...
We investigate the problem of increasing the spectral efficiency of current high rate telemetry systems in two different scenarios, which exploit one and two channels, respectively. We will analyze several techniques aimed at improving different stages of the transceiver scheme. We will optimize the transmission parameters and apply advanced receiver architectures, able to take into account part of...
Enabling ultra fast systems has been widely investigated during recent decades. Although polarization has been deployed from the beginning in satellite communications, nowadays it is being exploited to increase the throughput of satellite links. More precisely, the application of diversity techniques to the polarization domain may provide reliable, robust, and fast satellite communications. Better...
Delay Tolerant Network (DTN) comprises of nodes with small and limited resources including power and memory capacity. We propose the use of DTN as an alternate means of communication for the dissemination of emergency information in a post-disaster evacuation operation. We investigate the performance of DTN in providing emergency communication support services under packet dropping attacks. We consider...
Satellite networks are expected to support multimedia traffic flows, offering high capacity with QoS guarantees. This paper deals with Multipath-TCP (MPTCP), which exploits multiple TCP connections using different paths in order to improve user’s throughput. In this study, MPTCP is combined with network coding to protect TCP transmissions from packet losses caused by ON/OFF channels in mobile satellite...
In this paper, an iterative receiver that performs non-linear distortion noise cancellation is proposed for application at the user terminal in the DVB-S2X satellite forward link. The performance is assessed for a single-carrier time-division multiplexing (TDM) waveform with low carrier roll-off factors, e.g., down to 5%, and high baud rates, e.g., up to 34 MBaud in a 36-MHz transponder, in accordance...
In this paper, the performance of a Medium Earth Orbit (MEO) satellite trunking system operating in Ka-band in terms of capacity statistics is studied, taking into account sophisticated propagation and physical layer tools. First, the satellite system model is presented and some general considerations of the MEO constellation and network are given. Afterwards, a tool for generating atmospheric attenuation...
This paper presents a dynamic backhaul network in order to face some of the main 5G challenges such as 100% coverage, improved capacity or reduction in energy consumption. The proposed solution, elaborated within the SANSA H2020 project, is based on the seamless integration of the satellite component in a terrestrial network capable of reconfiguring its topology according to the traffic demands. The...
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Ultra Narrow Band (UNB) has been shown to be one of the best candidate technologies for Machine-To-Machine and Low Power Wide Area communications. Its properties – long range with small RF power – make it naturally attractive for satellite communications, but also draw new challenges compared to terrestrial systems where this technology is already deployed. In this paper we propose a general semi-analytical...
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