Planning and dynamic spectrum management in heterogeneous mobile networks with QoE optimization

The radio and network planning and optimisation are continuous processes that do not end after the network has been launched. To achieve the best trade-offs, especially between quality and costs, operators make use of several coverage and capacity enhancement methods. The research from this thesis proposes methods such as the implementation of cell zooming and Relay Stations (RSs) with dynamic sleep modes and Carrier Aggregation (CA) for coverage and capacity enhancements. Initially, a survey is presented on ubiquitous mesh networks implementation scenarios and an updated characterization of requirements for services and applications is proposed. The performance targets for the key parameters, delay, delay variation, information loss and throughput have been addressed for all types of services. Furthermore, with the increased competition, mobile operator’s success does not only depend on how good the offered Quality of Service (QoS) is, but also if it meets the end user’s expectations, i.e., Quality of Experience (QoE). In this context, a model for the mapping between QoS parameters and QoE has been proposed for multimedia traffic. The planning and optimization of fixed Worldwide Interoperability for Microwave Access (WiMAX) networks with RSs in conjunction with cell zooming has been addressed. The challenging case of a propagation measurement-based scenario in the hilly region of Covilhã has been considered. A cost/revenue function has been developed by taking into account the cost of building and maintaining the infrastructure with the use of RSs. This part of the work also investigates the energy efficiency and economic implications of the use of power saving modes for RSs in conjunction with cell zooming. Assuming that the RSs can be switched-off or zoomed out to zero in periods when the traffic exchange is low, such as nights and weekends, it has been shown that energy consumption may be reduced whereas cellular coverage and capacity, as well as economic performance may be improved. An integrated Common Radio Resource Management (iCRRM) entity is proposed that implements inter-band CA by performing scheduling between two Long Term Evolution – Advanced (LTE-A) Component Carriers (CCs). Considering the bandwidths available in Portugal, the 800 MHz and 2.6 GHz CCs have been considered whilst mobile video traffic is addressed. Through extensive simulations it has been found that the proposed multi-band schedulers overcome the capacity of LTE systems without CA. Result shown a clear improvement of the QoS, QoE and economic trade-off with CA

Planeamento, desenvolvimento e optimização de redes WiMAX

Esta dissertação aborda o planeamento de redes de banda larga IEEE 802.16. Após se realizarem algumas considerações gerais sobre a evolução da norma, assim como as suas principais características, são apresentados os aspectos essenciais das camadas físicas e MAC (Medium Access Control), assim como uma análise dos parâmetros de qualidade de serviço. Revêem-se as principais topologias de redes, as tecnologias de antenas SISO e MIMO e abordar-se, brevemente, aspectos de segurança em redes WiMAX. Realizou-se o dimensionamento de redes ponto-a-ponto a 5.4 GHz, uma entre o Hospital Sousa Martins (HSM), na Guarda, e a Faculdade de Ciências da Saúde da Universidade da Beira Interior (FCS UBI), na Covilhã, e outra entre a FCS e o Hospital Amato Lusitano (HAL), em Castelo Branco. Verificou-se a ausência de obstruções da linha de vista entre a localização das diversas estações e repetidores. Recorrendo ao modelo de Friis dimensiona-se os diversos feixes da ligação. A instalação final da ligação entre a FCS e o HAL com o equipamento BreezeNET B100 foi precedida de um teste de campo utilizando o equipamento BreezeNET B14. Recorrendo aos modelos de Friis modificado e SUI, realiza-se o planeamento celular na zona da Covilhã a 3.5 GHz, considerando a utilização do equipamento BreezeMAX 3000. Através de um teste de cobertura, na área sub-urbana da Covilhã, uma análise exaustiva da topografia e densidade de edificações da zona de teste, conclui-se da adequação da utilização do modelo de Friis modificado. Verifica-se que, através do cálculo do expoente de propagação médio na área de teste, é possível disponibilizar um modelo para a optimização do processo de planeamento celular. Para as duas zonas em que se dividiu a área de teste, Este e Noroeste, obtiveram-se valores de 2.31 e 2.8, com valores para o erro quadrático médio de 0.434 e 1.043, respectivamente. Realizou-se ainda um segundo planeamento celular a 5.4 GHz, para o equipamento BreezeACCESS VL. Apresentam-se os resultados do respectivo teste de cobertura, assim como a análise comparativa dos resultados obtidos.This thesis addresses the planning of IEEE 802.16 broadband networks. After presenting some general considerations on the evolution of the standard, e.g., its main features, the essential aspects of the physical and MAC (Medium Access Control) layers, as well as a study of the quality of service parameters are addressed. The main network topologies, the SISO e MIMO technologies are reviewed and some brief considerations on WiMAX networks security are also addressed. A 5.4 GHz point-to-point network was designed, to guarantee the link between the Hospital Sousa Martins (HSM), at Guarda, and the Health Sciences Faculty of the University of Beira Interior (FCS UBI), at Covilhã. Another link is between the FCS and the Hospital Amato Lusitano (HAL), at Castelo Branco. The obstruction of line-ofsight between the location of the transmitter and relay stations was verified. The link budget was computed by using the Friis model. The actual installation of the link between the FCS and HAL, in Castelo Branco, with the BreezeNET B100 equipment, was preceded by a field trial with BreezeNET B14 equipment. By using the modified Friis and SUI models, and by considering the use of BreezeMAX 3000 equipment at 3.5 GHz, the cellular planning of the area of the city of Covilhã was performed. Through a field trial, in the sub-urban area of Covilhã, an exhaustive analysis of the topography and density of buildings of the trial area, the adequacy of the modified Friis model was demonstrated. By computing the average propagation exponent for the field trial area, a model for the optimization of the cellular planning process was provided. For the two areas in which the trial area was split into, East and Northwest ones, the obtained values for the propagation exponent were 2.31 and 2.8, while the values for the mean square error were 0.434 and 1.043 respectively. One second cellular planning exercise was addressed at 5.4 GHz, for the BreezeACCESS VL equipment. The results for the field trials and the comparative analysis between the experimental and theoretical results were addressed