Time dynamic channel model for broadband fixed wireless access systems

Abstract Broadband fixed wireless access (BFWA) systems have been recognized as an effective first kilometer solution for broadband services to residential and business customers. The large bandwidth available in frequency bands above 20 GHz makes radio systems with very high capacities possible. Users can be offered bit rates in the order of several hundred Mbit/s, making (in terms of capacity) such radio links an alternative to optical fibre in many cases. High capacities BFWA links can be used to serve individual users directly or function as a backbone for lower capacity systems (both wire line and wireless) for local distribution of data. In addition, wireless always offers the freedom of broadband being away from the fixed access point. At mm-wavelengths the signals are sensitive to time dynamic propagation degradation caused by precipitation, vegetation and reflections/multipath from e.g. building surfaces. BFWA need to cope with location and time dependent interference and employ techniques such as interference cancellation and adaptive modulation and coding to optimise throughput during varying traffic load conditions. Multiple input multiple output (MIMO) and space-time coding, as well as adaptive (smart) antennas require knowledge of the channel dynamics as well. The objective of this master thesis is to develop a realistic time dynamic channel model for BFWA operating above 20 GHz utilising adaptive physical layer techniques. The channel model developed represents the time varying wideband channel impulse response including degradations due to multipath propagation, rain attenuation and vegetation fading. The channel model is suitable for simulating mitigation techniques for interference between base stations as well as adaptive modulation and coding techniques. The Maseng-Bakken statistical dynamic model of rain attenuation was adapted to model the rain attenuation. The dynamic vegetation effect was modelled as Nakagami-Rice distribution with K-factor depending on wind speed. A generic tapped delay line model was developed, in which the number of taps depend on maximum tap delay. This thesis is based on work in the project BROADWAN (www.broadwan.org), partly funded under the Information Society Technologies (IST) priority of the European Commission Sixth Framework Program.

5G Outlook – Innovations and Applications

5G Outlook - Innovations and Applications is a collection of the recent research and development in the area of the Fifth Generation Mobile Technology (5G), the future of wireless communications. Plenty of novel ideas and knowledge of the 5G are presented in this book as well as divers applications from health science to business modeling. The authors of different chapters contributed from various countries and organizations. The chapters have also been presented at the 5th IEEE 5G Summit held in Aalborg on July 1, 2016. The book starts with a comprehensive introduction on 5G and its need and requirement. Then millimeter waves as a promising spectrum to 5G technology is discussed. The book continues with the novel and inspiring ideas for the future wireless communication usage and network. Further, some technical issues in signal processing and network design for 5G are presented. Finally, the book ends up with different applications of 5G in distinct areas. Topics widely covered in this book are: • 5G technology from past to present to the future• Millimeter- waves and their characteristics• Signal processing and network design issues for 5G• Applications, business modeling and several novel ideas for the future of 5

Optimization of Spectrum Management in Massive Array Antenna Systems with MIMO

Fifth generation (5G), is being considered as a revolutionary technology in the telecommunication domain whose the challenges are mainly to achieve signal quality and great ability to work with free spectrum in the millimetre waves. Besides, other important innovations are the introduction of a more current architecture and the use of multiple antennas in transmission and reception. Digital communication using multiple input and multiple output (MIMO) wireless links has recently emerged as one of the most significant technical advances in modern communications. MIMO technology is able to offer a large increase in the capacity of these systems, without requiring a considerable increase in bandwidth or power required for transmission. This dissertation presents an overview of theoretical concepts of MIMO systems. With such a system a spatial diversity gain can be obtained by using space-time codes, which simultaneously exploit the spatial domain and the time domain. SISO, SIMO and MISO systems are differentiated by their channel capacity and their configuration in relation to the number of antennas in the transmitter/receiver. To verify the effectiveness of the MIMO systems a comparison between the capacity of SISO and MIMO systems has been performed using the Shannon’s principles. In the MIMO system some variations in the number of antennas arrays have been considered, and the superiority of transmission gains of the MIMO systems have been demonstrated. Combined with millimetre waves (mmWaves) technology, massive MIMO systems, where the number of antennas in the base station and the number of users are large, is a promising solution. SDR implementations have been performed considering a platform with Matlab code applied to MIMO 2x2 Radio and Universal Software Peripheral Radio (USRP). A detailed study was initially conducted to analyze the architecture of the USRP. Complex structures of MIMO systems can be simplified by using mathematical methods implemented in Matlab for the synchronization of the USRP in the receiver side. SISO transmission and reception techniques have been considered to refine the synchronization (with 16-QAM), thus facilitating the future implementation of the MIMO system. OpenAirInterface has been considered for 4G and 5G implementations of actual mobile radio communication systems. Together with the practical MIMO, this type of solution is the starting point for future hardware building blocks involving massive MIMO systems.A quinta geração (5G) está sendo considerada uma tecnologia revolucionária no setor de telecomunicações, cujos desafios são principalmente a obtenção de qualidade de sinal e grande capacidade de trabalhar com espectro livre nas ondas milimétricas. Além disso, outras inovações importantes são a introdução de uma arquitetura mais atual e o uso de múltiplas antenas em transmissão e recepção. A comunicação digital usando ligaçõe sem fio de múltiplas entradas e múltiplas saídas (MIMO) emergiu recentemente como um dos avanços técnicos mais significativos nas comunicações modernas. A tecnologia MIMO é capaz de oferecer um elevado aumento na capacidade, sem exigir um aumento considerável na largura de banda ou potência transmitida. Esta dissertação apresenta uma visão geral dos conceitos teóricos dos sistemas MIMO. Com esses sistemas, um ganho de diversidade espacial pode ser obtido utilizando códigos espaço-tempo reais. Os sistemas SISO, SIMO e MISO são diferenciados pela capacidade de seus canais e a sua configuração em relação ao número de antenas no emissor/receptor. Para verificar a eficiência dos sistemas MIMO, realizou-se uma comparação entre a capacidade dos sistemas SISO e MIMO utilizado os princípios de Shannon. Nos sistemas MIMO condecideraram-se algumas variações no número de agregados de antenas, e a superioridade dos ganhos de transmissão dos sistemas MIMO foi demonstrada. Combinado com a tecnologia de ondas milimétricas (mmWaves), os sistemas massivos MIMO, onde o número de antenas na estação base e o número de usuários são grandes, são uma solução promissora. As implementações do SDR foram realizadas considerando uma plataforma com código Matlab aplicado aos rádios MIMO 2x2 e Universal Software Peripheral Radio (USRP). Um estudo detalhado foi inicialmente conduzido para analisar a arquitetura da USRP. Estruturas complexas de sistemas MIMO podem ser simplificadas usando métodos matemáticos implementados no Matlab para a sincronização do USRP no lado do receptor. Consideraram-se técnicas de transmissão e recepção SISO para refinar a sincronização (com 16-QAM), facilitando assim a implementação futura do sistema MIMO . Considerou-se o OpenAirInterface para implementações 4G e 5G de sistemas reais de comunicações móveis. Juntamente com o MIMO na pratica, este tipo de solução é o ponto de partida para futuros blocos de construção de hardware envolvendo sistemas MIMO massivos

Improvement of 5G performance through network densification in millimetre wave band

Recently, there has been a substantial growth in mobile data traffic due to the widespread of data hungry devices such as mobiles and laptops. The anticipated high traffic demands and low latency requirements stemmed from the Internet of Things (IoT) and Machine Type Communications (MTC) can only be met with radical changes to the network paradigm such as harnessing the millimetre wave (mmWave) band in Ultra-Dense Network (UDN). This thesis presents many challenges, problems and questions that arise in research and design stage of 5G network. The main challenges of 5G in mmWave can be characterised with the following attributes: i- huge traffic demands, with very high data rate requirements, ii- high interference in UDN, iii increased handover in UDN, higher dependency on Line of Sight (LOS) coverage and high shadow fading, and iv-massive MTC traffic due to billions of connected devices. In this work, software simulation tools have been used to evaluate the proposed solutions. Therefore, we have introduced 5G network based on network densification. Network densification includes densification over frequency through mmWave, and densification over space through higher number of antennas, Higher Order Sectorisation (HOS), and denser deployment of small-cells. Our results show that the densification theme has significantly improved network capacity and user Quality of Experience (QoE). UDN network can efficiently raise the user experience to the level that 5G vision promised. However, one of the drawback of using UDN and HOS is the significant increase in Inter-Cell Interference (ICI). Therefore, ICI has been addressed in this work to increase the gain of densification. ICI can degrade the performance of wireless network, particularly in UDN due to the increased interference from surrounding cells. We have used Fractional Frequency Reuse (FFR) as ICI Coordination (ICIC) for UDN network and HOS environment. The work shows that FFR has improved the network performance in terms of cell-edge data throughput and average cell throughput, and maintain the peak data throughput at a certain threshold. Additionally, HOS has shown even greater gain over default sectored sites when the interference is carefully coordinated. To generalise the principle of densification, we have introduced Distributed Base Station (DBS) as the envisioned network architecture for 5G in mmWave. Remotely distributed antennas in DBS architecture have been harnessed in order to compensate for the high path loss that characterise mmWave propagation. The proposed architecture has significantly improved the user data throughput, decreased the unnecessary handovers as a result of dense network, increased the LOS coverage probability, and reduced the impact of shadow fading. Additionally, this research discusses the regulatory requirements at mmWave band for the Maximum Permissible Exposure (MPE). Finally, scheduling massive MTC traffic in 5G has been considered. MTC is expected to contribute to the majority of IoT traffic. In this context, an algorithm has been developed to schedule this type of traffic. The results demonstrate the gain of using distributed antennas on MTC traffic in terms of spectral efficiency, data throughput, and fairness. The results show considerable improvement in the performance metrics. The combination of these contributions has provided remarkable increase in data throughput to achieve the 5G vision of “massive” capacity and to support human and machine traffic

5G Outlook – Innovations and Applications

5G Outlook - Innovations and Applications is a collection of the recent research and development in the area of the Fifth Generation Mobile Technology (5G), the future of wireless communications. Plenty of novel ideas and knowledge of the 5G are presented in this book as well as divers applications from health science to business modeling. The authors of different chapters contributed from various countries and organizations. The chapters have also been presented at the 5th IEEE 5G Summit held in Aalborg on July 1, 2016. The book starts with a comprehensive introduction on 5G and its need and requirement. Then millimeter waves as a promising spectrum to 5G technology is discussed. The book continues with the novel and inspiring ideas for the future wireless communication usage and network. Further, some technical issues in signal processing and network design for 5G are presented. Finally, the book ends up with different applications of 5G in distinct areas. Topics widely covered in this book are: • 5G technology from past to present to the future• Millimeter- waves and their characteristics• Signal processing and network design issues for 5G• Applications, business modeling and several novel ideas for the future of 5

A High-speed Reconfigurable Free Space Optical Communication System Utilizing Software Defined Radio Environment

Free space optical (FSO) communication allows for high-speed data transmissions while also being extremely cost-effective by using visible or infrared wavelengths to transmit and receive data wirelessly through the free space channel. However, FSO links are highly susceptible to the effects of the atmosphere, particularly turbulence, smoke, and fog. On the other hand, FSO itself does not provide enough flexibility to address the issue of such blockage and obstruction caused by objects and atmospheric conditions. This research investigates, proposes, and evaluates a software defined multiple input multiple output (MIMO) FSO system to ensure link availability and reliability under weather conditions as part of the last mile access in the 5th generation, 6th generation, and beyond. Software defined radio (SDR) technology is adopted in order to provide a certain degree of flexibility to the optical wireless communications system. The scope of this research focuses on the design, validation, implementation, and evaluation of a novel adaptive switching algorithm i.e., activating additional transmitters of a MIMO FSO system using a software defined ecosystem. The main issues are the compactness of the experimental design; the limitation of software-oriented signal generation; robustness; reliability; and the quality of service. As part of the system design, the thresholding method, a decision-making process via the feedback link, and a spatial diversity technique is adopted to carry out the adaptive switching. The adaptive switching is performed via a feedback link in which the atmospheric loss and scintillation index are calculated for fog and turbulence respectively. The initial design is implemented in SDR/ GNURadio for a real-time emulation of the proposed system to enhance the system flexibility of a traditional MIMO FSO system. A bit-by-bit comparison is performed with the GNURadio signal processing block and BERT for a real-time BER estimation. However, based on the initial results, the switching mechanism can only overcome the effect of turbulence at a certain level. A new design to mainly mitigate the varying fog conditions is proposed based on the SDR-based adaptive switching for a gigabit ethernet (GbE) MIMO FSO system and tested in a 5 m dedicated atmospheric chamber. The proposed system is implemented using off-the-shelf components such as a media converter, small form pluggable transceivers, optical switch, and power meter to estimate the channel state information. A new Schmitt trigger-based thresholding method is also introduced. The proposed software defined GbE MIMO FSO with an adaptive switching algorithm is fabricated, implemented, and investigated. The results are also compared with the real-time simulated data. Since the purpose of this Ph.D. is to explain and demonstrate the proof of concept for the proposed SDR-MIMO FSO system, the emphasis has been on the design, evaluation, and minimal performance requirements rather than maximizing the data rate. The outcome of the thesis will be a huge degree of flexibility and mitigation property MIMO FSO can offer with the help of SDR. It will be shown that the designed system has the capability to provide data transmission with 99.999% availability with a packet error rate and data rate of 7.2 ×10−2 and ~120 Mbps respectively, under extremely harsh fog conditions with visibility V of < 11 m

Proceedings of the Fifth International Mobile Satellite Conference 1997

Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial communications services. While previous International Mobile Satellite Conferences have concentrated on technical advances and the increasing worldwide commercial activities, this conference focuses on the next generation of mobile satellite services. The approximately 80 papers included here cover sessions in the following areas: networking and protocols; code division multiple access technologies; demand, economics and technology issues; current and planned systems; propagation; terminal technology; modulation and coding advances; spacecraft technology; advanced systems; and applications and experiments

Redes de nova geração e o serviço universal de telecomunicações em Portugal

Doutoramento em Engenharia EletrónicaThis thesis addresses the issue of Universal Service for telecommunications in the context of the access networks of next generation. This work aims to contribute to the redefinition of the concept of universal telecommunications service focusing primarily on extending it to broadband services as economic and social development factor and taking into account the degree of dependence that currently, modern societies have for the different communication and information services. Complementarily it also intended to meet some of the challenges set out in the European 2020 agenda. Universal Service is defined here as access to a telecommunications network (with obligations in terms of type and quality of service for the operator), by of all citizens at any country's geographical location, with uniform and accessible price. The approach adopted is the State as a mentor for social equity, respectful of the liberalized market dynamics but also knowledgeable of the requirements of modern telecommunications services and its relationship with the different technologies available. The possibility of subsidizing is assumed. The Universal Service´s provision is subject to open to all operators, which are assumed to possess other profitability businesses, than the Universal Service, using technologies similar to those prescribed for the respective Universal Service provision contest. Although the work has components of economic and financial analysis, the approach is the engineering point of view, looking for help to identify technical and organizational solutions which offer prospects for the dissemination and adoption of next generation network solutions. As a point of departure the work gives an overview on the state of the art access networks , trying to identify which of the differences between this reality and possible scenarios for next-generation network with potential access to the generality of the people . The case of the Portuguese reality will be given special attention, taking into account their specific characteristics in terms of geography, demography, economics and market dynamics. The main results of this work are: • Identification of possible scenarios for the evolution of existing networks, in particular in areas with deficit coverage. • Identification of possible operating models and business to the materialization of the above scenarios developed and its economic analysis in an attempt to determine the critical factors associated with sustainability and / or need for subsidies. • Contribution to the regulatory framework of new generation networks from the point of view of the constraints of technology and the specifics of the Universal Service.Esta tese aborda a questão do serviço universal de telecomunicações no contexto das redes de acesso de nova geração. Este trabalho pretende contribuir para a redefinição do conceito de Serviço Universal de Telecomunicações concentrando-se principalmente em estendê-lo a serviços de banda larga como factor de desenvolvimento económico e social e tendo em conta o grau de dependência que, actualmente, as sociedades modernas têm em relação aos diferentes serviços de comunicação e informação. De forma complementar pretende-se também ir ao encontro de alguns dos desafios enunciados na Agenda Europeia 2020. Serviço Universal é aqui definido como o acesso a uma rede de telecomunicações (com obrigações em termos de tipo e qualidade de serviço para o operador), por parte de todos os cidadãos, em qualquer localização geográfica do país, a preços uniformes e acessíveis. A perspectiva adoptada é a Estatal como mentor da equidade social, respeitador das dinâmicas de mercado liberalizado mas também conhecedor dos requisitos dos modernos serviços de telecomunicações e da sua relação com as diferentes tecnologias disponíveis. A possibilidade de subsidiação é assumida. A prestação de Serviço Universal é sujeita a concurso aberto a todos os operadores, que se assume possuírem outros negócios, que não apenas o Serviço Universal, com rentabilidade e usando tecnologias semelhantes às preconizadas para a respectiva prestação de Serviço Universal. Embora o trabalho desenvolvido tenha componentes de análise económico-financeira, a abordagem utilizada é a de engenharia, procurando contribuir para a identificação de soluções técnicas e organizacionais que possam oferecer perspectivas sustentáveis para a disseminação e adopção das soluções redes de nova geração. Como ponto de partida o trabalho apresenta uma visão geral sobre o estado da arte das redes de acesso, procurando identificar quais os diferenciais existentes entre essa realidade e a de possíveis cenários de rede de próxima geração com potencial de acesso para a generalidade dos cidadãos. O caso da realidade Portuguesa será objecto de uma atenção especial, tendo em consideração as suas especificidades em termos de geografia, demografia, economia e dinâmicas do mercado. Os principais resultados deste trabalho são os seguintes: • Identificação de possíveis cenários para a evolução das redes actuais, nomeadamente em áreas com deficit de cobertura de rede. • Identificação de possíveis modelos de operação e negócio para a materialização dos cenários acima desenvolvidos e respectiva análise económica, como tentativa de determinar os factores críticos associados à sua sustentabilidade e /ou necessidade de subsidiação. • Contributo para o quadro regulatório das Redes de Nova Geração sob o ponto de vista dos constrangimentos das tecnologias e das especificidades do Serviço Universal

Impulse response measurements of local multipoint distribution service (LMDS) channel in Singapore

IEEE International Conference on Communications1521-52521