DVB-NGH: the Next Generation of Digital Broadcast Services to Handheld Devices

This paper reviews the main technical solutions adopted by the next-generation mobile broadcasting standard DVB-NGH, the handheld evolution of the second-generation digital terrestrial TV standard DVB-T2. The main new technical elements introduced with respect to DVB-T2 are: layered video coding with multiple physical layer pipes, time-frequency slicing, full support of an IP transport layer with a dedicated protocol stack, header compression mechanisms for both IP and MPEG-2 TS packets, new low-density parity check coding rates for the data path (down to 1/5), nonuniform constellations for 64 Quadrature Amplitude Modulation (QAM) and 256QAM, 4-D rotated constellations for Quadrature Phase Shift Keying (QPSK), improved time interleaving in terms of zapping time, end-to-end latency and memory consumption, improved physical layer signaling in terms of robustness, capacity and overhead, a novel distributed multiple input single output transmit diversity scheme for single-frequency networks (SFNs), and efficient provisioning of local content in SFNs. All these technological solutions, together with the high performance of DVB-T2, make DVB-NGH a real next-generation mobile multimedia broadcasting technology. In fact, DVB-NGH can be regarded the first third-generation broadcasting system because it allows for the possibility of using multiple input multiple output antenna schemes to overcome the Shannon limit of single antenna wireless communications. Furthermore, DVB-NGH also allows the deployment of an optional satellite component forming a hybrid terrestrial-satellite network topology to improve the coverage in rural areas where the installation of terrestrial networks could be uneconomical.Gómez Barquero, D.; Douillard, C.; Moss, P.; Mignone, V. (2014). DVB-NGH: the Next Generation of Digital Broadcast Services to Handheld Devices. IEEE Transactions on Broadcasting. 60(2):246-257. doi:10.1109/TBC.2014.2313073S24625760

Long term perspectives of TV convergence towards 5G: Mobile and fixed applications

The third generation partnership project (3GPP) has defined in Release 14 the new evolved version of Multimedia Broadcast Multicast Service system, whose characteristics are well aligned to the technical requirements coming from the broadcast sector for TV services. This paves the way to allow broadcasters and content aggregators to deliver mobile TV content over cooperative broadcast high power high tower and mobile low power low tower network infrastructures, using a converging broadcast 3GPP technology. In a longer term perspective, in the 2020 decade, might this full-IP convergent technology become a candidate successor of DVB-T2 (ATSC or ISDB-T) also for digital terrestrial television home services? Is there a technical and business case for converging fixed and mobile TV on the same networks and technologies? The study investigates the performance of 3GPP Release 14 in theoretical, regular networks and in a real area around Turin (Italy), trying to give a technical background to answer the above strategic questions

Advanced techniques for spectrally efficient DVB-S2X systems

We investigate different techniques to improve the spectral efficiency of systems based on the DVB-S2 standard, when the transmitted signal bandwidth cannot be increased because it has already been optimized to the maximum value allowed by transponder filters. We will investigate and compare several techniques to involve different sections of the transceiver scheme. The techniques that will be considered include the use of advanced detection algorithms, the adoption of time packing, and the optimization of the constellation and shaping pulses. The LDPC codes recently proposed for the evolution of the DVB-S2 standard will be considered, as well as the adoption of iterative detection and decoding. Information theoretical analysis will be followed by the study of practical modulation and coding schemes

Air Interfaces for Satellite Based Digital TV Broadcasting in the Railway Environment

This paper deals with the analysis of possible air interfaces to be employed in order to provide digital TV services to high speed trains via satellite. This turns out to be an extremely challenging issue, since in addition to traditional impairments characterizing the land mobile satellite channel, one has to face the presence of frequent tunnels, whose duration can easily reach several kilometers, and the presence of a variety of peculiar obstacles, such as electrical trellises and posts with and without brackets, which may result in frequent and deep fades. A large variety of possible solutions, based on standardized air interfaces with proper modifications, are analyzed by means of extensive software simulations, showing that effective solutions can be devised. Some consideration concerning the deployment of terrestrial gap-fillers to bridge the satellite connectivity inside long railway tunnels, large train station and within dense urban areas are also briefly addresse

A 4th4^{\rm th}-order accurate finite volume method for ideal classical and special relativistic MHD based on pointwise reconstructions

International audienceWe present a novel implementation of a genuinely $4^{\rm th}$-order accurate finite volume scheme for multidimensional classical and special relativistic magnetohydrodynamics (MHD) based on the constrained transport (CT) formalism. The scheme introduces several novel aspects when compared to its predecessors yielding a more efficient computational tool. Among the most relevant ones, our scheme exploits pointwise to pointwise reconstructions (rather than one-dimensional finite volume ones), employs the generic upwind constrained transport averaging and sophisticated limiting strategies that include both a discontinuity detector and an order reduction procedure. Selected numerical benchmarks demonstrate the accuracy and robustness of the method

Advanced techniques for spectrally efficient DVB-S2X systems

We investigate different techniques to improve the spectral efficiency of systems based on the DVB-S2 standard, when the transmitted signal bandwidth cannot be increased because it has already been optimized to the maximum value allowed by transponder filters. We will investigate and compare several techniques involving different sections of the transceiver scheme. The techniques that will be considered include the use of advanced detection algorithms, the adoption of time packing, and the optimization of the constellation and shaping pulses. The low-density parity-check codes recently proposed for the evolution of the DVB-S2 standard will be considered, as well as the adoption of iterative detection and decoding. Information-theoretical analysis will be followed by the study of practical modulation and coding schemes. Copyright © 2015 John Wiley & Sons, Ltd

LTE Backhauling Over MEO-Satellites

This paper considers satellite backhauling of eNodeBs aboard vehicles like trains, planes, (cruise) ships and coaches. Current LTE releases do not envisage backhauling of such moving eNodeBs. A Medium Earth Orbit (MEO) satellite configuration like the O3b system and link budgets for the four mentioned vehicles are assumed for the considered scenario. The most promising potential network architecture is analysed by considering several use cases and thus identifying open issues. These issues are examined by analysis and simulation, where the employed real-time simulator implements both the LTE core network, base stations and UEs as well as video codecs on the application layer and a two-way DVB-S2/ACM satellite link emulator

Transmission parameters optimization and receiver architectures for DVB-S2X systems

Summary The second-generation specification of the digital video broadcasting for satellite (DVB-S2) was developed in 2003 with the aim of improving the existent broadcasting standard DVB-S. The main new features introduced by DVB-S2 included increased baud rates, higher cardinality constellations (up to 32 points), and more efficient binary codes. The extension to DVB-S2, approved in 2014 with the name DVB-S2X, together with continuous technological evolution, moves further steps in this direction, with the use of constellations with cardinality up to 256 points, improved granularity of modulation and coding schemes, and the possibility to increase the baud rate. In this scenario, it is important to be able to ascertain what is the best transceiver structure, starting from the choice of the shaping pulse and the baud rate of the transmitted signals and ending with the most promising receiver architectures, with the aim of maximizing the spectral efficiency. In this paper, we will discuss some of the aspects of this investigation, namely, the optimization of transmission parameters and the description of an efficient receiver. We will then assess the performance of the proposed scheme in comparison with a classical DVB-S2 architecture. Some synchronization aspects will also be discussed, to account for the impairments introduced by the channel