An algorithm proposal for a minimum cost SDR multi-standard system using graph theory

International audienceThe design of future multi-standard systems remains a challenge due to increasing flexibility requirements. Promising solutions include designing flexible radio architectures that exploit common aspects between the different set of standards cohabiting in the device. In this paper, graph theory appears and particularly the study of directed hypergraphs, which helps in the research concerning minimum cost multistandard designs. A cost function which calculates the cost of any possible option of implementation is mentioned but its derivations won't be in the scope of this paper. Our objective is to optimize this proposed cost function to its minimum possible value and thus solving the optimization problem that finds balance between flexibility and computing efficiency. For this, we propose a Minimum Cost Design (MCD) algorithm capable of selecting the option which has the minimum cost to pay and will present its complete set of instructions in this paper. This algorithm exploits various definitions and notations of directed hypergraphs

Large-scale Spatial Distribution Identification of Base Stations in Cellular Networks

The performance of cellular system significantly depends on its network topology, where the spatial deployment of base stations (BSs) plays a key role in the downlink scenario. Moreover, cellular networks are undergoing a heterogeneous evolution, which introduces unplanned deployment of smaller BSs, thus complicating the performance evaluation even further. In this paper, based on large amount of real BS locations data, we present a comprehensive analysis on the spatial modeling of cellular network structure. Unlike the related works, we divide the BSs into different subsets according to geographical factor (e.g. urban or rural) and functional type (e.g. macrocells or microcells), and perform detailed spatial analysis to each subset. After examining the accuracy of Poisson point process (PPP) in BS locations modeling, we take into account the Gibbs point processes as well as Neyman-Scott point processes and compare their accuracy in view of large-scale modeling test. Finally, we declare the inaccuracy of the PPP model, and reveal the general clustering nature of BSs deployment, which distinctly violates the traditional assumption. This paper carries out a first large-scale identification regarding available literatures, and provides more realistic and more general results to contribute to the performance analysis for the forthcoming heterogeneous cellular networks

D13.2 Techniques and performance analysis on energy- and bandwidth-efficient communications and networking

Deliverable D13.2 del projecte europeu NEWCOM#The report presents the status of the research work of the various Joint Research Activities (JRA) in WP1.3 and the results that were developed up to the second year of the project. For each activity there is a description, an illustration of the adherence to and relevance with the identified fundamental open issues, a short presentation of the main results, and a roadmap for the future joint research. In the Annex, for each JRA, the main technical details on specific scientific activities are described in detail.Peer ReviewedPostprint (published version

D13.1 Fundamental issues on energy- and bandwidth-efficient communications and networking

Deliverable D13.1 del projecte europeu NEWCOM#The report presents the current status in the research area of energy- and bandwidth-efficient communications and networking and highlights the fundamental issues still open for further investigation. Furthermore, the report presents the Joint Research Activities (JRAs) which will be performed within WP1.3. For each activity there is the description, the identification of the adherence with the identified fundamental open issues, a presentation of the initial results, and a roadmap for the planned joint research work in each topic.Preprin

Comparison of the transmission modes of 5G networks with a high density of base stations distributed according to Poisson Point Process

International audienceMobile video traffic is growing rapidly with the advent of connected mobile devices such as smartphones and tablets, especially in the context of 5G networks. To cope with this traffic growth, cellular networks have undergone significant improvements in the recent years, especially via broadcast transmission when it comes to delivering mobile multimedia services to a large number of users. In this paper, we address the issue of performance evaluation of unicast and broadcast modes, when considering a network modeled with base stations distributed according to the PPP (Poisson Point Process) law instead of the traditional hexagonal model. The impact of varying the density of base stations is thus evaluated. The impact of using beamforming with the unicast mode is also evaluated using a certain number of antennas per sector of tri-sector base stations. The performance evaluation of unicast (even using beamforming) and broadcast modes is thus performed in terms of CDF (Cumulative Distribution Function) of the SINR (Signal to Interference and Noise Ratio), average SINR of the system, and the worst case SINR, taking into account the inter-cell interference

Energy consumption management under quality-of-service constraints in the context of small cell networks

International audienceIn this paper, we propose an analytical solution for the joint optimization of spectral efficiency and energy consumption of future deployed cellular networks based on small cell base stations (BSs). We derive an optimization problem that consists in minimizing the energy consumption under the constraint of meeting the throughput and spectral efficiency challenges of 5G - and upcoming 6G - networks. The relaxed problem is convex and therefore there is an optimal solution that can be found numerically and/or derived analytically. Comparative studies show a perfect accuracy of the analytical approach compared to the numerical solution. Particular attention is thus paid to the evaluation of the impact of the system parameters on the optimal metrics of energy consumption and spectral efficiency

Optimization of the trade-off between spectral efficiency and energy efficiency in the sub-terahertz context

International audienceTo answer to future challenges of communications, applications will need more bandwidth, more throughput, lower latency, seamless connectivity, as well as improved spectral and energy efficiencies, etc. One of the solutions considered by the community is the use of sub-THz bands (0.1 THz to 10 THz). However, communicating at such high frequencies has a cost, such as lower range and high energy consumption. In this paper, we are interested in jointly optimizing energy consumption and spectral efficiency while keeping in mind the baseband units' energy consumption. Numerical analysis shows that there is an optimal trade-off between energy consumption and spectral efficiency that yields the lowest energy consumption while meeting the qualities of service (QoS) of sub-THz communications. Particular attention is thus paid on the evaluation of the impact of certain system parameters such as transmission distance, power consumption of baseband units and bandwidth on the optimal energy consumption and spectral efficiency metrics

, Influence des canaux Gaussien et de Rayleigh sur la distribution du PAPR dans les systèmes MIMO-OFDM

Il s'agit de présenter des résultats théoriques validés par des simulations concernant le PAPR d'un système MIMO-OFDM. Le PAPR est calculé à la réception d'un système de télécommunication perturbé par des canaux de Gauss et de Rayleigh. En considérant les fonctions de répartition des signaux, nous proposons des développement théoriques du PAPR dans un contexte MIMO-OFDM. L'originalité du travail réside dans la prise en compte du canal de propagation. Les résultats montrent une dégradation importante du PAPR dans le cas d'un canal de Rayleigh. De plus, nous montrons que cette dégradation diminue lorsque le nombre d'antennes d'émission du système MIMO-OFDM augmente

Gaussian and Flat Rayleigh Fading Channel Influences on PAPR Distribution in MIMO-OFDM Systems

5 pagesInternational audienceMultiple-input multiple-output orthogonal frequency division multiplexing systems (MIMO-OFDM) has became a promising candidate for high performance 4G broadband wireless communications. However, like OFDM, one main disadvantage of MIMO-OFDM is that the signals transmitted on different antennas may exhibit a prohibitively large peakto- average power ratio (PAPR). In this paper, the influence of gaussian and flat Rayleigh fading channel on the PAPR of MIMO-OFDM passband signals at the receiver-side have been analyzed. A mathematical expression for complementary cumulative distribution function (CCDF) of the PAPR has been derived which depends on the number of transmitting antennas and the parameters of channel

Interference management for better coverage of future cellular networks

International audienceCoverage maximization is a key objective in order to meet the requirements of future cellular networks. In this context, interference management plays a key role in the coverage optimization of future cellular networks with a high density of base stations (BSs). Indeed, coverage performance is closely related to interference management and will be degraded if the interference is not managed. In this context, we propose two solutions to reduce interference, consisting of using the beamforming approach on the one hand, and using the inter-cell cooperation approach on the other hand where the BSs in the cooperation area use simultaneous transmission via the MB-SFN (Multicast Broadcast - Single Frequency Network) technique. Thus, this paper starts from a high-density BSs deployment scenario, and focuses on the study and comparison of the coverage of these two approaches, while considering that the BSs are randomly and independently distributed according to the Poisson Point Process (PPP) instead of the traditional hexagonal model. Particular attention is paid to the evaluation of the impact of some parameters on the coverage probability under a variety of system conditions