Multicast Scheduling and Resource Allocation Algorithms for OFDMA-Based Systems: A Survey

Multicasting is emerging as an enabling technology for multimedia transmissions over wireless networks to support several groups of users with flexible quality of service (QoS)requirements. Although multicast has huge potential to push the limits of next generation communication systems; it is however one of the most challenging issues currently being addressed. In this survey, we explain multicast group formation and various forms of group rate determination approaches. We also provide a systematic review of recent channel-aware multicast scheduling and resource allocation (MSRA) techniques proposed for downlink multicast services in OFDMA based systems. We study these enabling algorithms, evaluate their core characteristics, limitations and classify them using multidimensional matrix. We cohesively review the algorithms in terms of their throughput maximization, fairness considerations, performance complexities, multi-antenna support, optimality and simplifying assumptions. We discuss existing standards employing multicasting and further highlight some potential research opportunities in multicast systems

Interoperability Among Heterogeneous Networks for Future Aeronautical Communications

General surger

Software-defined satellite cloud RAN

This is the peer reviewed version of the following article: Ahmed, T., Dubois, E., Dupé, J.-B., Ferrús, R., Gélard, P., and Kuhn, N. (2018) Software-defined satellite cloud RAN. Int. J. Satell. Commun. Network., 36: 108–133, which has been published in final form at 10.1002/sat.1206. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.This paper provides an assessment study on the virtualization of a Digital Video Broadcasting - Satellite - Second Generation (DVB-S2)/ Digital Video Broadcasting - Return Channel Satellite - Second Generation (DVB-RCS2) satellite ground infrastructure and proposes a framework, named Satellite Cloud Radio Access Network (SatCloudRAN), that aims to ease the integration of satellite components in forthcoming 5G systems. Special attention is given to the design of SatCloudRAN by considering the split and placement of virtualized and nonvirtualized functions while taking into account the characteristics of the transport links connecting both type of functions. We assess how virtualization and softwarization technologies, namely, network function virtualization and software-defined networking, can deliver part of the satellite gateway functionalities as virtual network functions and achieve a flexible and programmable control and management of satellite infrastructure. Under the network function virtualization paradigm, building virtual network function blocks that compose a satellite gateway have been identified, and their interaction exhibited. This paper also gives insights on how the SatCloudRAN approach can allow operators to provide software-defined networking-based (1) bandwidth on demand, (2) dynamic Quality of Service, and (3) satellite gateway diversity.Peer ReviewedPreprin

Satellite Communications

This study is motivated by the need to give the reader a broad view of the developments, key concepts, and technologies related to information society evolution, with a focus on the wireless communications and geoinformation technologies and their role in the environment. Giving perspective, it aims at assisting people active in the industry, the public sector, and Earth science fields as well, by providing a base for their continued work and thinking

Combined Source and Channel Strategies for Optimized Video Communications

ISBN 978-953-7619-70-

Call admission control for interactive multimedia satellite networks.

Master of Science in Engineering (Electronic). University of KwaZulu-Natal, Durban 2015.Satellite communication has become an integral component of global access communication network due mainly to its ubiquitous coverage, large bandwidth and ability to support for large numbers of users over fixed and mobile devices. However, the multiplicity of multimedia applications with diverse requirements in terms of quality of service (QoS) poses new challenges in managing the limited and expensive resources. Furthermore, the time-varying nature of the propagation channel due to atmospheric and environmental effects also poses great challenges to effective utilization of resources and the satisfaction of users’ QoS requirements. Efficient radio resource management (RRM) techniques such as call admission control (CAC) and adaptive modulation and coding (AMC) are required in order to guarantee QoS satisfaction for user established connections and realize maximum and efficient utilization of network resources. In this work, we propose two CAC policies for interactive satellite multimedia networks. The two policies are based on efficient adaptation of transmission parameters to the dynamic link characteristics. In the first policy which we refer to as Gaussian Call Admission Control with Link Adaptation (GCAC-LA), we invoke the central limit theorem to statistically multiplex rate based dynamic capacity (RBDC) connections and obtain an aggregate bandwidth and required capacity for the multiplex. Adaptive Modulation and Coding (AMC) is employed for transmission over the time-varying wireless channel of the return link of an interactive satellite network. By associating users’ channel states to particular transmission parameters, the amount of resources required to satisfy user connection requirements in each state is determined. Thus the admission control policy considers in its decision, the channel states of all existing and new connections. The performance of the system is investigated by simulation and the results show that AMC significantly improves the utilization and call blocking performance by more than twice that of a system without link adaptation. In the second policy, a Game Theory based CAC policy with link adaptation (GTCAC-LA) is proposed. The admission of a new user connection under the GTCAC-LA policy is based on a non-cooperative game that is played between the network (existing user connections) and the new connection. A channel prediction scheme that predicts the rain attenuation on the link in successive intervals of time is also proposed. This determines the current resource allocation for every source at any point in time. The proposed game is played each time a new connection arrives and the strategies adopted by players are based on utility function, which is estimated based on the required capacity and the actual resources allocated. The performance of the CAC policy is investigated for different prediction intervals and the results show that multiple interval prediction scheme shows better performance than the single interval scheme. Performance of the proposed CAC policies indicates their suitability for QoS provisioning for traffic of multimedia connections in future 5G networks

Enlace de retorno satelital DVB-RCS2 : modelagem de fila e otimização de alocação de recursos baseada em teoria dos jogos

Tese (doutorado) — Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Elétrica, 2022.É esperado que satélites tenham um papel fundamental no futuro dos sistemas de comunicação, integrando-se às infraestruturas terrestres. Esta dissertação de mestrado propõe três contribuições principais: primeiramente, se apresenta um arcabouço de simulação capaz de prover detalhes da performance de redes de comunicação satelital em cenários realistas. Este arcabouço aplica uma metodologia orientada a eventos, modelando a rede de comunicação como um sistema baseado em eventos discretos (DES), focando no enlace de retorno do protocolo DVB-RCS2. Três diferentes cenários simulados demonstram os possíveis usos das saídas do simulador para entender o comportamento dinâmico da rede e alcançar um ponto ótimo de operação do sistema. Cada cenário explora uma característica diferente do simulador, enquanto cobre um grande território de usuários, que em nosso caso estudo o país de escolha foi o Brasil. Em um segundo tópico, este trabalho introduz um novo algoritmo modificado do método de alocação de timeslots baseado em teoria dos jogos, aplicando-se no protocolo DVB-RCS2. Este procedimento considera a eficiência espectral do terminal como um parâmetro de peso para o problema de otimização convexa resultante da solução da barganha de Nash. Este novo método garante o cumprimento dos requisitos de Qualidade de Serviço (QoS) enquanto provê uma medida de justiça maior; os resultados mostram uma melhoria de 5% na medida de justiça, com uma diminuição de 75% no desvio padrão de justiça entre os quadros, também alcançando um aumento de 12% na satisfação individual média pela alocação de capacidade aos terminais. Por final, apresentamos uma modelagem alternativa para o enlace de retorno do DVB-RCS2 usando cadeias de Markov, predizendo parâmetros tradicionais de fila como a intensidade de tráfego, tempo médio de espera, dentre outros. Utilizamos dados coletados de uma série de simulações usando o arcabouço orientado a eventos para validar o modelo de filas como uma aproximação numérica útil para o cenário real de aplicação. Nós apresentamos o algoritmo de alocação de controle do parâmetro alfa (GTAC) que consegue controlar o tempo médio de espera de um RCST na fila, respeitando um limiar de tempo enquanto otimiza a taxa média média de transmissão de dados dos terminais.Satellite networks are expected to play a vital role in future communication systems, with complex features and seamless integration with ground-based infrastructure. This dissertation proposes three main contributions: firstly, it presents a novel simulation framework capable of providing a detailed assessment of a satellite communication’s network performance in realistic scenarios, employing an event-driven methodology and modeling the communications network as a DES (discrete event system). This work focuses on the return link of the Digital Video Broadcast Return Channel via Satellite (DVB-RCS2) standard. Three different scenarios demonstrate possible uses of the simulator’s output to understand the network’s dynamic behavior and achievable optimal system operation. Each scenario explores a different feature of the simulator. The simulated range covers a large territory with thousands of users, which in our case study was the country of Brazil. In the second theme, this work introduces a novel algorithm modification for the conventional game theory-based time slot assignment method, applying it to the DVB-RCS system. This procedure considers the spectral efficiency as a weighting parameter. We use it as an input for the resulting convex optimization problem of the Nash Bargaining Solution. This approach guarantees the fulfillment of Quality of Service (QoS) constraints while maintaining a higher fairness measure; results show a 5% improvement in fairness, with a 73% decrease in the standard deviation of fairness between frames, while also managing to reach a 12.5% increase in average normalized terminal BTU allocation satisfaction. Lastly, we present an alternative queuing model analysis for the DVB-RCS2 return link using Markov chains, developed to predict traditional queue parameters such as traffic intensity, average queue size, average waiting time, among others. We used data gathered from a series of simulations using the DES framework to validate this queuing model as a useful numerical approximation to the real application scenario, and, by the end of the scope, we present the alpha allocation algorithm (GTAC) that can maintain the average waiting time of a terminal in the queue to a threshold while optimizing the average terminal throughput