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In addition to the traditional TDM/FDM, the advanced television systems committee (ATSC) 3.0 next generation digital TV standard has adopted state-of-the-art coding and modulation, as well as the new layered division multiplexing (LDM) technology. The ATSC 3.0 system is able to provide higher data throughput, more robust reception, better spectrum efficiency, and flexible service combinations in one RF channel with different robustness and reception conditions. Due to the adoption of a two-layer LDM, the coverage for ATSC 3.0 is very different from the legacy one-transmitter-one-coverage ATSC 1.0 system. With the new enabling technologies, the ATSC 3.0 can greatly increase the coverage/service areas, reduce the distance between co-channel assignments, and introduce local program insertion and targeted advertisement. This paper addresses the ATSC 3.0 coverage and co-channel interference issues, by using the two-layer LDM technology with different operating parameters. Simulations demonstrate that, similar to the 4G long term evolution, the ATSC 3.0 co-channel assignment could be reduced to two times the service coverage radius. This means an improvement of the spectrum efficiency by up to four times in comparison with today’s system. It is also proved through simulations that significant TV program gains can be obtained with this new system. The deployment of single frequency networks can further improve the coverage and reduce the interference. [ABSTRACT FROM AUTHOR]

This paper presents a generic methodology to optimize constellations based on their geometrical shaping for bit-interleaved coded modulation (BICM) systems. While the method can be applicable to any wireless standard design it has been tailored to two delivery scenarios typical of broadcast systems: 1) robust multimedia delivery and 2) UHDTV quality bitrate services. The design process is based on maximizing the BICM channel capacity for a given power constraint. The major contribution of this paper is a low complexity optimization algorithm for the design of optimal constellation schemes. The proposal consists of a set of initial conditions for a particle swarm optimization algorithm, and afterward, a customized post processing procedure for further improving the constellation alphabet. According to the broadcast application cases, the sizes of the constellations proposed range from 16 to 4096 symbols. The BICM channel capacities and performance of the designed constellations are compared to conventional quadrature amplitude modulation constellations for different application scenarios. The results show a significant improvement in terms of system performance and BICM channel capacities under additive white Gaussian noise and Rayleigh independently and identically distributed channel conditions. [ABSTRACT FROM PUBLISHER]

Two of the main drawbacks of the current broadcasting services are, on the one hand, the lack of flexibility to adapt to the new generation systems requirements, and on the other hand, the incapability of taking a piece of the current mobile services market. In this paper, layered division multiplexing (LDM), which grew out of the concept of Cloud Txn, is presented as a very promising technique for answering those challenges and enhancing the capacity of broadcasting systems. The major contribution of this paper is to present the first comprehensive study of the LDM performance behavior. In particular, in this paper, the theoretical considerations of the LDM implementation are completed with the first computer based simulations and laboratory tests, covering a wide range of stationary channels and the mobile TU-6 channel. The results will support LDM as a strong candidate for multiplexing different services in the next generation broadcasting systems, increasing both flexibility and performance. [ABSTRACT FROM PUBLISHER]

This paper presents the field trials carried out in Bilbao (Spain) for testing and analyzing the performance of the DVB-T2 indoor (fixed and pedestrian) reception. Test services with different DVB-T2 and T2-Lite configuration modes have been broadcasted and indoor measurements have been carried out. As a result, signal to noise ratio threshold values for DVB-T2 indoor reception have been obtained. These values update those provided by previous studies and are also valid for planning tools to be used by broadcasters in the development of DVB-T2 networks. [ABSTRACT FROM AUTHOR]