Matteo Anedda

64-APSK Constellation and Mapping Optimization for Satellite Broadcasting Using Genetic Algorithms

DVB-S2 and DVB-SH satellite broadcasting standards currently deploy 16- and 32-amplitude phase shift keying (APSK) modulation using the consultative committee for space data systems (CCSDS) mapping. Such standards also include hierarchical modulation as a mean to provide unequal error protection in highly variable channels over satellite. Foreseeing the increasing need for higher data rates, this paper tackles the optimization of 64-APSK constellations to minimize the mean square error between the original and received symbol. Optimization is performed according to the sensitivity of the data to the channel errors, by means of genetic algorithms, a well-known technique currently used in a variety of application domains, when close form solutions are impractical. Test results show that through non-uniform constellation and asymmetric symbol mapping, it is possible to significantly reduce the distortion while preserving bandwidth efficiency. Tests performed on real signals based on perceptual quality measurements allow validating the proposed scheme against conventional 64-APSK constellations and CCSDS mapping.

Heuristic optimization of DVB-T/H SFN coverage using PSO and SA algorithms

This paper studies two of the available heuristic algorithms to optimize the digital broadcasting networks planning. Particle Swarm Optimization (PSO) and Simulated Annealing (SA) are compared working in different OFDM modes. These algorithms manipulate the information of the network with static delays in order to maximize the covered area as well as possible at minimum cost. Particle Swarm Optimization (PSO) and Simulated Annealing (SA) are compared working in a different OFDM modes and synchronization strategies. Furthermore, they have been used to estimate the coverage and the interference degree of the network planning placed in the Basque Country, in northern Spain.

Adaptive real-time multi-user access network selection algorithm for load-balancing over heterogeneous wireless networks

The coexistence of several wireless technologies gives users a wide connectivity choice. However, in this heterogeneous context with the even growth of multimedia data demand and continuous amendments of network conditions, the best network selection represents a crucial issue. In this paper the authors propose a novel Adaptive Real-time Multi-user Access Network Selection (ARMANS) load balancing algorithm, taking into account not only the real-time global traffic load on each network, but also considering the different classes of traffic. The simulation results show that the proposed solution improves both QoS and load balancing in comparison with the case when a classic network selection with no traffic type load balancing is employed.

E-ARMANS: Energy-aware device-oriented video delivery in heterogeneous wireless networks

The latest technological development of smartphones and tablets has supported an exponential increase in demand for multimedia content from their users. At the same time, the battery-related technologies for these devices have not advanced at the same pace and are an important limitation factor for future developments. Therefore there is a need for energy-aware solutions for multimedia delivery to such mobile devices and this paper focuses on energy saving in the context of multimedia distribution at high quality levels over loaded heterogeneous wireless networks. The paper proposes an energy-aware device-oriented video delivery algorithm (E-ARMANS) as a solution to a twofold problem: traffic load balancing over wireless networks and energy consumption optimization. E-ARMANS evaluates both network conditions and device characteristics and provides the user the best connectivity in given conditions. Testing in comparison with a performance-oriented approach shows how E-ARMANS increases average battery life with 40%, 47%, and 32%, while delivering video content to devices with 1080p, 720p, and 576p resolutions, respectively.

A 5G cellular technology for distributed monitoring and control in smart grid

In Smart Grids the flow of electricity and information is strictly interrelated with the management and control of the electricity supply system. ICT is not only an extension or a modernization of the power system equipment, but a fundamental requirement for supporting the distribution network monitoring, operation and control. To enable monitoring and control of the Smart Grid and accommodate the large realtime data flow between controlled equipment and the distribution management system it is necessary the deployment of advanced sensors and measurement systems along with the communication network infrastructure. In this paper two different strategies for power network monitoring and control are compared: an LTE-based centralized management approach and a 5G-based distributed management approach. The two types of communications systems are compared considering their performances during fault management in a Smart Grid scenario.

Subjective video quality assessments for 4K UHDTV

There is no ITU recommendation concerning subjective tests for video quality assessment in UHD resolution. A clear methodology needs to be established. In this paper we present a subjective quality assessment test of HEVC/H.265 compressed 4K Ultra-High-Definition (UHD) videos in a laboratory viewing environment. We describe the methodology employed, including the setup room based on different parameters such as user position, viewing angle and viewing distance, and the video dataset we used which has been previously employed. Finally, we make some considerations on the experience collected on the methodology and on the fact that the same experiment when conducted in different countries with different languages and cultures may lead to different results.

Real-time load optimization for multimedia delivery content over heterogeneuos wireless network using a MEW approach

The significant increment in the number of users that need broadband multimedia system, relative radio resources, and the evolution of the devices has encouraged to search for different methods to manage heterogeneous wireless networks. One solution to this problem is to make traffic balancing on heterogeneous networks, so that none of the available networks for a given user will be saturated avoiding performance decay. This paper proposes a novel Multiplicative Exponential Weighting (MEW) approach that manages the access network selection. MEW combines several inputs such as power of the received signal, throughput, packet delay, cost-per-user, the requested type of traffic, and type of device. The obtained results have shown an improvement of 15% in average PSNR, and 20% in terms of delay and throughput, compared to the algorithms presented in the literature.

Load-shared redundant interface for LTE access network

Technological and industrial revolution has led to rapid increase in the request for various services in Long Term Evolution (LTE). These requests characterize different network traffic and are handled adequately in order to maintain a defined level of quality of service (QoS). The number and type of services requested are probabilistic and complex to handle. Conventionally, sustained increase in network traffic is handled by cell splitting techniques with proper network management schemes and/or increase in resources allocated to a cell. However, cell splitting is constrained by the availability of site location, energy consumption, frequent handoff, equipment cost etc., and the increase in resources is inconceivable due limited available communication resources. To solve these challenges, this work proposed a solution that leads the installation and activation of a load-shared redundant network interface as a complement to LTE base station. The interface was managed by load balancing technique, frequency reuse and carrier diversification. The work was simulated with Network Simulator 3 (ns-3.24) and tested with video traffic. The results obtained showed that the proposed scenario conserved 15.2% energy while achieving similar performance in terms of delay, throughput and loss ratio with the cell division technique.

Coverage optimization for DVB-T2 SFNs using ITU-R P.1546 and ITU-R P.1812

In this paper, two available propagation prediction methods for point-to-area terrestrial services in the VHF-UHF bands are compared: ITU-R P.1546 and ITU-R P.1812. This work allows evaluating the path-specific propagation prediction method that best approximates effective and real radio-wave propagation in single frequency networks (SFN) for digital video broadcasting (DVB). Multipath interference (MPI) minimization at receiver antenna is obtained through the static delay adjustment, antenna gain, elevation orientation and azimuth. MPI minimization and thus, coverage optimization have been reached using the heuristic genetic algorithm (GA). Simulation results show that the methods compared provide different propagation prediction performances according to different geography of territory. The proposed approach has been validated for DVB-T2 SFN transmitters network planning in Sardinia island (Italy), Basque Country (Spain) and Flanders (Belgium).