Digital Video Broadcasting - Next Generation Handheld Research Articles

Capacity Improvement for DVB-NGH with Dual-Polarized MIMO Spatial Multiplexing and Hybrid Beamforming

Multiple-input multiple-output (MIMO) antenna scheme is an effective technique for future terrestrial broadcasting systems such as digital video broadcasting-next-generation handheld (DVB-NGH) to overcome the limits on information theory of traditional single-antenna wireless communications without any additional bandwidth or increased transmit power. In this paper, we propose a hybrid beamforming scheme for dual-polarized MIMO spatial multiplexing DVB-NGH broadcasting systems. The system of interest makes use of phase shifters and amplitude attenuators for the digital-analog precoder at beamforming stage of the transmitter end to maximize the signal-to-noise ratio to increase the channel capacity of the DVB-NGH systems. At the receiver end, the maximum likelihood (ML) detector is used to evaluate the system performance. We consider the signal-to-interference-and-noise ratio (SINR) and the achievable average capacity for the DVB-NGH MIMO with various FFT sizes, number of transmit antennas, and different modulation schemes. The performance results on bit error rate, channel capacity, and beampatterns show that the proposed hybrid beamforming and dual-polarized MIMO spatial multiplexing schemes provide more robustness against signal interference by beamforming and/or nulling techniques. The simulation results also show that the proposed system achieves higher capacity than the existing MIMO schemes for the DVB-NGH systems.

Performance of Open-Loop MIMO Precoder With Cross-Polarized Antennas Over Correlated Channels With an LOS Component

Open-loop multiple-input multiple-output (MIMO) precoders, that do not require channel information, were recently proposed to mitigate the performance degradation of spatial multiplexing (SM) due to spatial correlations and/or line-of-sight (LOS) component. The open-loop MIMO precoder technique has been adopted in next generation broadcasting systems, such as digital video broadcasting-next generation handheld (DVB-NGH) and advanced television systems committee (ATSC) 3.0 standards. Furthermore, in DVB-NGH and ATSC 3.0, cross-polarized antennas have been employed in order to overcome the insufficient antenna separation for co-polarized antennas, which can enhance the performance over high correlation and LOS conditions. In this paper, we analyze and evaluate the performance of the open-loop MIMO precoders with cross-polarized antennas over correlated channels with an LOS component. We first study the statistical property of the MIMO channel with cross-polarized antennas on the basis of the measurement-based channel model. Next, we derive pairwise error probability (PEP) of the SM with the open-loop MIMO precoder. Through the PEP derivation, we evaluate the performance of each open-loop MIMO precoder against the spatial correlations and LOS component with the effect of cross-polarized antennas. The simulation results are presented to demonstrate the performance of the open-loop MIMO precoders over various channel conditions.

Layered Division Multiplexing With Multi-Radio-Frequency Channel Technologies

The advanced television system committee (ATSC) is to release the next-generation U.S. digital terrestrial television standard, known as ATSC 3.0. Layered division multiplexing (LDM) is one of the new physical layer technologies included in the standard, which enables the efficient provision of mobile and fixed services by superposing two independent signals with different power levels. ATSC 3.0 has also adopted a novel transmission technique known as channel bonding (CB), which splits the data of a service into two sub-streams that are modulated and transmitted over two radio-frequency (RF) channels. This paper investigates the potential use cases, implementation aspects, and performance advantages, for combining LDM with CB and also with the multi-RF channel technology time frequency slicing (TFS) introduced in digital video broadcasting - terrestrial second generation (DVB-T2) (as an informative annex) and digital video broadcasting - next generation handheld (DVB-NGH) which allows distributing the data of a service across two or more RF channels by means of time slicing and frequency hopping.

Improved Polarized 2x2 MIMO Spatial Multiplexing Method for DVB-NGH System

Recently terrestrial digital broadcasting systems have experienced a growth with the demand of high-data rate. In order to meet such demand, the multiple-input multiple-output (MIMO) technology has received wide attention. This paper proposes a pre-coding method, which provides high-space channel correlation for the improved performance over terrestrial broadcasting channels when the MIMO spatial multiplexing (SM) is adopted for digital video broadcasting-next generation handheld systems. When signals with two different modulation orders are transmitted through two antennas, a method that is based on non-uniform power is also proposed for improved reception performance. To optimize the proposed method, phase shifting values for the pre-coding method and appropriate non-uniform power ratio are obtained. These obtained parameters are applied to a terrestrial broadcasting system, and then the performance improvement over the conventional SM is shown through computer simulations.

Technical Solutions for Local Service Insertion in DVB-NGH Single Frequency Networks

Current digital terrestrial television networks make use of either single frequency networks (SFN) or multifrequency networks (MFN). These network topologies are not ideally suited for delivery of both global and local services in an efficient way. MFNs enable the efficient transmission of local services but need a significant amount of frequency spectrum. The basic principle of SFNs is that all transmitters radiate the same signal synchronized in time and frequency, therefore are especially suitable for global services due to mutual support of the signal by multiple transmitters. Without violating the SFN principle, local services meant to address sub-regions of an SFN must therefore be transmitted throughout the whole network, causing inefficient distribution of local services. This paper describes the complementary techniques adopted by the next generation mobile broadcasting standard digital video broadcasting-next generation handheld for providing global and local contents in SFN topologies: hierarchical modulation (H-LSI) and orthogonal local services insertion (O-LSI) techniques. H-LSI uses hierarchical modulation to transmit local services on top of the global services in areas close to the transmitters, by transmitting the local services in the low priority stream and the global services in the high priority stream. The O-LSI scheme specifies groups of OFDM subcarriers in specific OFDM symbols for the exclusive use of particular transmitters to transmit local services. For both techniques, the transmission of local content through the whole SFN network can be scheduled in a way that different local areas do not interfere with each other. In addition to the description of both H-LSI and O-LSI schemes, the applicability of these approaches in terms of network topologies, implementation issues, and performance evaluation are analyzed.

Dimensioning and Profit Sharing in Hybrid LTE/DVB Systems to Offer Mobile TV Services

Our aim in this work is to develop profit sharing strategies for coooperative 4G Long Term Evolution (LTE) and Digital Video Broadcasting - Next Generation Handheld (DVB-NGH) systems offering mobile TV service. We first study the capacity of the hybrid system for offering such a service and derive the associated cost for each network. We then focus on the sharing of profit between LTE and DVB operators as well as TV channels providers, taking into account the subscription revenues as well as the infrastructure and operation costs. We consider two cases: one in which both LTE and DVB networks are managed by a single operator and one in which the operators are separate. In both cases, we derive closed-form expressions for each player profit share using coalition game concept Shapley value. We further obtain the players optimal strategies, at the Nash equilibrium, where each player tries to maximize its own profit.

MIMO for DVB-NGH, the next generation mobile TV broadcasting [Accepted From Open Call

DVB-NGH (Digital Video Broadcasting - Next Generation Handheld) is the next generation technology for mobile TV broadcasting, which has been developed by the DVB project with the most advanced transmission technologies. DVB-NGH is the first broadcasting standard to incorporate multiple-input multiple-output (MIMO) as the key technology to overcome the Shannon limit of single antenna communications. MIMO techniques can be used to improve the robustness of the transmitted signal by exploiting the spatial diversity of the MIMO channel, but also to achieve increased data rates through spatial multiplexing. This article describes the benefits of MIMO that motivated its incorporation in DVB-NGH, reviews the MIMO schemes adopted, and discusses some aspects related to the deployment of MIMO networks in DVB-NGH. The article also provides a feature comparison with the multi-antenna techniques for 3GGP's LTE/LTE-Advanced for cellular networks. Finally, physical layer simulation results calibrated within the DVB-NGH standardization process are provided to illustrate the gain of MIMO for the next generation of mobile TV broadcasting.