Статті в журналах: "Dense radio access network"

1

Atanasov, Ivaylo I., and Evelina N. Pencheva. "Programmability of Connectivity Control." Elektronika ir Elektrotechnika 27, no. 2 (April 29, 2021): 78–85. http://dx.doi.org/10.5755/j02.eie.28819.

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Network programmability and edge computing as key features of next generation communications enable innovative services. While the programmability is focused on the core network of the fifth-generation system, the edge computing moves the network intelligence to the radio access network. This paper presents a study on the programmability of connectivity control as a function of radio access network using Multi-access Edge Computing. The capability of using more than one radio access technology simultaneously enhances reliability and increases the throughput, especially in dense networks. Opening the radio access network interfaces for programmability of multi-connectivity enables analytics applications to control the device connections to multiple radio links simultaneously based on information of radio conditions, user location or specific policies. The research novelty is in opening the radio access network interfaces for edge applications to access connectivity control.

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2

Fokin, Grigoriy A. "SIMULATION OF ULTRA DENSE 5G RADIO ACCESS NETWORKS WITH BEAMFORMING." T-Comm 15, no. 5 (2021): 4–21. http://dx.doi.org/10.36724/2072-8735-2021-15-5-4-21.

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In this paper, we investigate the connectivity and probability of successful radio reception in the Poisson model of a 5G ultra-dense radio access network formed by devices with the possibility of location aware beamforming. The difference be-tween the proposed model and the existing prototypes is the complex account for the gains of devices, as well as the influence of radio wave propagation losses, slow and fast fading in the radio channel on the performance of the radio access network. The study is carried out for sessions of directional and omni-directional radio communication, and the beamforming mode is based on the preliminary positioning of neighboring devices. Mathematical modeling of a set of simultaneously operating radio lines in the Poisson model of an ultra-dense 5G radio access network makes it possible to estimate the gain in connectivity and the probability of successful radio reception when forming a beam based on preliminary positioning of devices in comparison with the case of omnidirectional antennas. The results of mathematical modeling of a ultra-dense radio access network with devices equipped with six-element circular antenna arrays showed a significant increase in connectivity indicators and the probability of successful radio reception in comparison with the case of omnidirectional antennas and confirmed the possibility of spatial multiplexing of simultaneous transmissions with a territorial separation of devices on 20% of the range of radio coverage based on the signal-to-noise ratio criterion. The result of the study is the establishment of the dependences of the connectivity and the probability of successful radio reception for an ultra-dense 5G radio access network, built on the basis of devices operating in the adaptive diagramming mode, as well as confirmation of the possibilities of spatial multiplexing of simultaneously operating transceiver devices with their territorial separation by 20% of the range of radio coverage based on the signal-to-interference ratio criterion. The obtained dependences of connectivity and the probability of successful radio reception allows to scientifically substantiate construction of an initial approximation of ultra-dense 5G radio access network from devices with the possibility of beamforming based on positioning, taking into account practical recommendations for their territorial diversity with an ultra-dense distribution.

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3

Fokin, G. "Evaluation of Interference in Ultra-Dense 5G Radio Access Networks with Beamforming." Telecom IT 8, no. 4 (December 23, 2020): 35–59. http://dx.doi.org/10.31854/2307-1303-2020-8-4-35-59.

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In this paper, we investigate the dependence of the level of intersystem interference on the beam width of the adaptively formed antenna radiation pattern and the territorial separation of neighboring devices in ultra-dense 5G radio access networks. The results of simulation modeling of a radio access network based on 19 base stations with the parameterization of the antenna array gain by the width of the radiation pattern in the horizontal plane show that when the base station beam is di-rected to the user device and narrowed from 360° to 5°, the level of intrasystem interference decreases by 15 dB compared with the case of omnidirectional antennas. The results of simulation of a radio access network based on 19 three-sector base stations with planar antenna arrays of 64 elements illustrate a significant reduction in the level of interference in comparison with the case of omnidirectional antennas and, in order to obtain zones of a positive signal-to-noise ratio, confirm the need for a territorial separation of neighboring devices by 10–20 % of the range of radio coverage.

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4

Koudouridis, Georgios P., and Pablo Soldati. "Trading off Network Density with Frequency Spectrum for Resource Optimization in 5G Ultra-Dense Networks." Technologies 6, no. 4 (December 1, 2018): 114. http://dx.doi.org/10.3390/technologies6040114.

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To effectively increase the capacity in 5G wireless networks requires more spectrum and denser network deployments. However, due to the increasing network density, the coordination of network and spectrum management becomes a challenging task both within a single operator’s network and among multiple operators’ networks. In this article, we develop new radio resource management (RRM) algorithms for adapting the frequency spectrum and the density of active access nodes in 5G ultra-dense networks (UDNs) to the traffic load and the user density in different geographical areas of the network. To this end, we formulate a network optimization problem where the allocation of spectrum bandwidth and the density of active access nodes are optimized to minimize a joint cost function, and we exploit Lagrange duality techniques to develop provably optimal network-scheduling algorithms. In particular, we develop density algorithms for two application scenarios. The first scenario solves the resource management problem for an operator of an ultra-dense network with exclusive access to a pool of frequency resources, while the second scenario applies to the management of the network density of collocated UDNs that belong to multiple operators sharing the same frequency spectrum. Simulation results demonstrate how effectively the algorithms can adapt the allocation of the spectrum allocation and the density of active access nodes over space and time.

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5

Gui, Jinsong, and Jianglin Liu. "An Efficient Radio Access Resource Management Scheme Based on Priority Strategy in Dense mmWave Cellular Networks." Wireless Communications and Mobile Computing 2020 (September 15, 2020): 1–19. http://dx.doi.org/10.1155/2020/8891660.

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In millimeter wave (mmWave) communication systems, beamforming-enabled directional transmission and network densification are usually used to overcome severe signal path loss problem and improve signal coverage quality. The combination of directional transmission and network densification poses a challenge to radio access resource management. The existing work presented an effective solution for dense mmWave wireless local area networks (WLANs). However, this scheme cannot adapt to network expansion when it is applied directly to dense mmWave cellular networks. In addition, there is still room for improvement in terms of energy efficiency and throughput. Therefore, we firstly propose an efficient hierarchical beamforming training (BFT) mechanism to establish directional links, which allows all the small cell base stations (SBSs) to participate in the merging of training frames to adapt to network expansion. Then, we design a BFT information-aided radio access resource allocation algorithm to improve the downlink energy efficiency of the entire mmWave cellular network by reasonably selecting beam directions and optimizing transmission powers and beam widths. Simulation results show that the proposed hierarchical BFT mechanism has the smaller overhead of BFT than the existing BFT mechanism, and the proposed BFT information-aided radio access resource allocation algorithm outperforms the existing corresponding algorithm in terms of average energy efficiency and throughput per link.

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6

Gribaudo, Marco, Daniele Manini, and Carla Fabiana Chiasserini. "Modelling user radio access in dense heterogeneous networks." Performance Evaluation 146 (March 2021): 102167. http://dx.doi.org/10.1016/j.peva.2020.102167.

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7

Patkar, Ankit. "5G Wireless Technology." International Journal for Research in Applied Science and Engineering Technology 10, no. 3 (March 31, 2022): 1519–24. http://dx.doi.org/10.22214/ijraset.2022.40930.

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Abstract: After the up rise of 4G wireless mobile technology takes place; researchers, mobile operator industries representative, academic institutions have started to look into the advancement (technological) towards 5G communication networks due to some main demands that are meliorated data rates, better capacity, minimized latency and better QoS (Quality of Service). To established the 5G mobile communication technological foundation, various research works or projects entailing main mobile infrastructure manufacturers, academia and international mobile network operators have been introduced recently. Nevertheless, 5G mobile services to be made available for use, their architecture, and their performance have not been evidently explicated. In this paper, we represent thorough overview of 5G the next generation mobile technology. We mainly throws light on 5G network architecture, 5G radio spectrum, ultra-dense radio access networks (UDRAN), traffic offloading of mobile, cognitive radio (CR), software defined radio (SDR), software defined networking (SDN), mixed infrastructure, and 5G network impact on the society. Keywords: 5G wireless technology, evolution from 4G to 5G

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8

Kalfas, George, Dimitris Palianopoulos, Agapi Mesodiakaki, Marios Gatzianas, Christos Vagionas, Ronis Maximidis, and Nikos Pleros. "A QoS-Enabled Medium-Transparent MAC Protocol for Fiber-Wireless 5G RAN Transport Networks." Applied Sciences 12, no. 17 (August 30, 2022): 8708. http://dx.doi.org/10.3390/app12178708.

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In order to meet the ever-increasing 5G and beyond Radio Access Network (RAN) densification demands, Fiber-Wireless transport networks are expected to play a key role in accelerating 5G deployment by providing the essential RAN flexibility, while at the same time avoiding costly fiber-trenching. Due to the inefficiency of the Radio-and-Fiber (R&F) networks for application in dense RAN topologies, Analog-Radio-over-Fiber (A-RoF) technology is regarded as a key enabling solution, since it greatly simplifies the remote antenna while offering very high spectral efficiency. For this type of dense A-RoF network, new and efficient Medium-Transparent-Medium Access Control (MT-MAC) protocols are required that can concurrently arbitrate optical and wireless resources, while at the same time offering the necessary Quality-of-Service (QoS) for correct operation of the combined Fronthaul/Midhaul/Backhaul segments present in 5G disaggregated RANs. In this paper, we propose a QoS-enabled MT-MAC (qMT-MAC) protocol that can combine Fronthaul/Midhaul/Backhaul flows under the same framework, while satisfying the strict delay and jitter requirements set by the relevant standards. Results show that qMT-MAC concurrently achieves the delay and jitter requirements for combined Fronthaul/Midhaul/Backhaul traffic even when loads approach the network’s capacity, while attested enhanced prioritization policies can offer up to a 64% delay reduction over State-of-the-Art MT-MAC protocols.

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9

He, Shiwen, Yiyun Chen, Ju Ren, Yongming Huang, Luxi Yang, and Yaoxue Zhang. "Decentralized Precoding for Cache-Enabled Ultra-Dense Radio Access Networks." IEEE Wireless Communications Letters 8, no. 2 (April 2019): 404–7. http://dx.doi.org/10.1109/lwc.2018.2873671.

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10

Shepard, Timothy J. "A channel access scheme for large dense packet radio networks." ACM SIGCOMM Computer Communication Review 26, no. 4 (October 1996): 219–30. http://dx.doi.org/10.1145/248157.248176.

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11

Kułacz, Łukasz, Adrian Kliks, Paweł Kryszkiewicz, and Bartosz Bossy. "Dynamic Transmit Profile Selection in Dense Wireless Networks." Sensors 21, no. 1 (December 28, 2020): 134. http://dx.doi.org/10.3390/s21010134.

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The development of wireless networks can be characterized by both the increased number of deployed network nodes as well as their greater heterogeneity. As a consequence, the distance between the neighboring nodes decreases significantly, the density of such a wireless network is very high, and it brings to the mind the analogy to the human brain and nervous system, where a highly simplified scheme of information delivery is applied. Motivated by this similarity, in this paper, we study the possibility of the application of various transmission profiles in order to optimize the overall energy consumption in such dense wireless networks. The transmission profile specifies the radio access and energy consumption of the wireless transceiver (network node), and is characterized by the tuple of parameters, e.g., the total transmit power or minimal required signal-to-noise ratio (SNR). In the considered multi-hop network, we assume that each node can be set to the most promising transmission profile to achieve some predefined goals, such as (sensor) network reliability or transmission energy efficiency. We have proposed the new graph-based routing algorithm in such a dense wireless network, where total power consumption of message delivery is minimized by multihop and multimode transmission. The theoretical definition of the prospective transmission schemes is supported by the analysis of the results of the simulation experiments.

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12

Habbal, Adib, Swetha Indudhar Goudar, and Suhaidi Hassan. "Context-Aware Radio Access Technology Selection in 5G Ultra Dense Networks." IEEE Access 5 (2017): 6636–48. http://dx.doi.org/10.1109/access.2017.2689725.

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13

González González, David, Edward Mutafungwa, Beneyam Haile, Jyri Hämäläinen, and Héctor Poveda. "A Planning and Optimization Framework for Ultra Dense Cellular Deployments." Mobile Information Systems 2017 (2017): 1–17. http://dx.doi.org/10.1155/2017/9242058.

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To accommodate the ever-expanding wireless data traffic volumes, mobile network operators are complementing their macrocellular networks by deploying low-power base stations (or small cells) to offload traffic from congested macrocells and to reuse spectrum. To that end, Ultra Dense Network (UDN) deployments provide means to aggressively reuse spectrum, thus providing significant enhancements in terms of system capacity. However, these deployments entail several challenges, including the increased complexity in network planning and optimization. In this paper, we propose a versatile optimization framework for planning UDN deployments. The planning and optimization framework is underpinned by metrics that consider scalability in terms of number of users, cost of densification, and fairness. The proposed methodology is evaluated using a real-world UDN planning case. The numerical results expose a number of interesting insights, including the impact of different bandwidth allocation strategies and spatial service demand distribution on the performance of various network topologies. Specifically, we provide a performance comparison of the optimized UDN topologies versus random (unplanned), regular grid, and heuristically derived UDN topologies. This comparison further underlines the need for flexible network planning and optimization frameworks as different operator performance metrics of interest may require different radio access networks configurations.

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14

Sahinel, Doruk, Simon Rommel, and Idelfonso Tafur Monroy. "Resource Management in Converged Optical and Millimeter Wave Radio Networks: A Review." Applied Sciences 12, no. 1 (December 27, 2021): 221. http://dx.doi.org/10.3390/app12010221.

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Three convergent processes are likely to shape the future of the internet beyond-5G: The convergence of optical and millimeter wave radio networks to boost mobile internet capacity, the convergence of machine learning solutions and communication technologies, and the convergence of virtualized and programmable network management mechanisms towards fully integrated autonomic network resource management. The integration of network virtualization technologies creates the incentive to customize and dynamically manage the resources of a network, making network functions, and storage capabilities at the edge key resources similar to the available bandwidth in network communication channels. Aiming to understand the relationship between resource management, virtualization, and the dense 5G access and fronthaul with an emphasis on converged radio and optical communications, this article presents a review of how resource management solutions have dealt with optimizing millimeter wave radio and optical resources from an autonomic network management perspective. A research agenda is also proposed by identifying current state-of-the-art solutions and the need to shift all the convergent issues towards building an advanced resource management mechanism for beyond-5G.

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15

Allawi, Yazan M., Alaelddin F. Y. Mohammed, Joohyung Lee, and Seong Gon Choi. "A Sustainable Business Model for a Neutral Host Supporting 5G and beyond (5GB) Ultra-Dense Networks: Challenges, Directions, and Architecture." Sensors 22, no. 14 (July 12, 2022): 5215. http://dx.doi.org/10.3390/s22145215.

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With the deployment of the fifth generation (5G) mobile network systems and the envisioned heterogeneous ultra-dense networks (UDNs), both small cell (SmC) and distributed antenna system (DAS) technologies are required by mobile network operators (MNOs) and venue owners to support multiple spectrum bands, multiple radio access technologies (RATs), multiple optical central offices (COs), and multiple MNOs. As a result, the neutral host business model representing a third party responsible for managing the network enterprise on behalf of multiple MNOs has emerged as a potential solution, mainly influenced by the desire to provide a high user experience without significantly increasing the total cost of ownership (TCO). However, designing a sustainable business model for a neutral host is a nontrivial task, especially when considered in the context of 5G and beyond (5GB) UDNs. In this paper, under an integrated optical wireless network infrastructure, we review how SmC and DAS technologies are evolving towards the adoption of the neutral host business model and identify key challenges and requirements for 5GB support. Thus, we explore recent candidate advancements in heterogeneous network integration technologies for the realization of an efficient 5GB neutral host business model design capable of accommodating both SmC and DAS. Furthermore, we propose a novel design architecture that relies on virtual radio access network (vRAN) to enable real-time dynamic resource allocation and radio over Ethernet (RoE) for flexible and reconfigurable fronthaul. The results from our simulations using MATLAB over two real-life deployment scenarios validate the feasibility of utilizing switched RoE considering end-to-end delay requirements of 5GB under different switching schemes, as long as the queuing delay is kept to a minimum. Finally, the results show that incorporating RoE and vRAN technologies into the neutral host design results in substantial TCO reduction by about 81% in an indoor scenario and 73% in an outdoor scenario.

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16

Tesema, Fasil B., Ahmad Awada, Ingo Viering, Meryem Simsek, and Gerhard P. Fettweis. "Multiconnectivity for Mobility Robustness in Standalone 5G Ultra Dense Networks with Intrafrequency Cloud Radio Access." Wireless Communications and Mobile Computing 2017 (2017): 1–17. http://dx.doi.org/10.1155/2017/2038078.

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Capacity and ultra-reliable communication are some of the requirements for 5th generation (5G) networks. One of the candidate technologies to satisfy capacity requirement is standalone Ultra Dense Network (UDN). However, UDNs are characterized by fast change of received signal strength that creates mobility challenges in terms of increased handovers and connection failures. In this paper, a low layer multiconnectivity scheme is presented for standalone UDN aiming at ultra-reliable communication that is free of interruptions from handover procedures and connection failures. Furthermore, the problem in managing of the set of serving cells, that are involved in multiconnectivity for each user, is formulated. By using numerical method, feasible scheme for management of the set of serving cells is derived. Performance of the proposed multiconnectivity scheme is evaluated and compared against single connectivity. It is shown that the proposed multiconnectivity scheme outperforms single connectivity considerably in terms of connection failures and cell-edge throughput.

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17

Grishin, I., and G. Fokin. "Estimation of Permissible Angular Separation of Devices for the Beamforming Scenario in Ultra-Dense Millimeter-Wave Radio Access Networks." Herald of the Siberian State University of Telecommunications and Informatics 16, no. 4 (November 25, 2022): 10–26. http://dx.doi.org/10.55648/1998-6920-2022-16-4-10-26.

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This study is devoted to estimating the allowable angular separation between devices operating in ultra-dense radio access networks in the millimeter frequency range, for the subsequent formation of a three-dimensional radiation pattern with optimal characteristics by the base station antenna array. The content of this work can be divided into two parts. In the first part of this work, a mathematical formalization of the number of radio emission sources estimation and their angular coordinates is given. Based on the presented mathematical model and the developed simulation program, in the second part of the work, the study and determination of the accuracy characteristics of the angular separation of devices depending on interference in the scenario of diagram formation of ultra-dense radio access networks when devices use the combined azimuth and elevation measurement algorithm are carried out.

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18

Ozturk, Metin, Attai Ibrahim Abubakar, Joao Pedro Battistella Nadas, Rao Naveed Bin Rais, Sajjad Hussain, and Muhammad Ali Imran. "Energy Optimization in Ultra-Dense Radio Access Networks via Traffic-Aware Cell Switching." IEEE Transactions on Green Communications and Networking 5, no. 2 (June 2021): 832–45. http://dx.doi.org/10.1109/tgcn.2021.3056235.

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19

Rendon Schneir, Juan, Konstantinos Konstantinou, Julie Bradford, Gerd Zimmermann, Heinz Droste, Rafael Canto Palancar, and Ade Ajibulu. "Cost assessment of multi-tenancy for a 5G broadband network in a dense urban area." Digital Policy, Regulation and Governance 22, no. 2 (March 5, 2020): 53–70. http://dx.doi.org/10.1108/dprg-10-2019-0086.

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Purpose 5G systems will enable an improved transmission performance and the delivery of advanced communication services. To meet the expected requirements, operators will need to invest in network modernisation, with the radio access network being the most expensive network component. One possible way for operators to reduce this investment would be via sharing of resources by means of a multi-tenancy concept. This implies that a mobile service provider may use the common infrastructure of one or various infrastructure providers, whereby it provides services to multiple tenants. This paper aims to study the expected cost savings in terms of capital expenditures (CAPEX) and operational expenditures (OPEX) that can be achieved when using a cloudified 5G multi-tenant network. Design/methodology/approach A cost model was used. The study period is 2020-2030 and the study area consists of three local districts in central London, UK. Findings This paper describes that the total cost reduction achieved when using multi-tenancy for a 5G broadband network in comparison with the case where operators make the investment independently ranges from 5.2% to 15.5%. Research limitations/implications Further research is needed to assess the cost implications of network sharing for 5G on a regional or nationwide basis. Originality/value Very little quantitative research about the cost implications of network sharing under 5G networks has been published so far. This paper sheds light on the economic benefits of multi-tenancy in a 5G broadband network.

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20

Moysen, Jessica, Lorenza Giupponi, and Josep Mangues-Bafalluy. "A Mobile Network Planning Tool Based on Data Analytics." Mobile Information Systems 2017 (2017): 1–16. http://dx.doi.org/10.1155/2017/6740585.

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Planning future mobile networks entails multiple challenges due to the high complexity of the network to be managed. Beyond 4G and 5G networks are expected to be characterized by a high densification of nodes and heterogeneity of layers, applications, and Radio Access Technologies (RAT). In this context, a network planning tool capable of dealing with this complexity is highly convenient. The objective is to exploit the information produced by and already available in the network to properly deploy, configure, and optimise network nodes. This work presents such a smart network planning tool that exploits Machine Learning (ML) techniques. The proposed approach is able to predict the Quality of Service (QoS) experienced by the users based on the measurement history of the network. We select Physical Resource Block (PRB) per Megabit (Mb) as our main QoS indicator to optimise, since minimizing this metric allows offering the same service to users by consuming less resources, so, being more cost-effective. Two cases of study are considered in order to evaluate the performance of the proposed scheme, one to smartly plan the small cell deployment in a dense indoor scenario and a second one to timely face a detected fault in a macrocell network.

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21

Amali, C., and B. Ramachandran. "Enabling Key Technologies and Emerging Research Challenges Ahead of 5G Networks: An Extensive Survey." JOIV : International Journal on Informatics Visualization 2, no. 3 (April 20, 2018): 133. http://dx.doi.org/10.30630/joiv.2.3.128.

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The evolution towards 5G networks is expected to slake the growing thirst of internet traffic with improved Quality of Service (QoS) and reduced energy consumption and cost. The increased penetration of smart devices and induction of arising multimedia applications, together with high quality video services are already crafting a milestone on existing cellular networks. These surging demands dictate that radical enhancements need to be made in cellular architecture to drift towards ultra-dense networks. The 5G system is envisioned to achieve improved data rate, increased capacity, decreased latency, and enhanced spectral efficiency in order to provide technical solution for the challenges behind the cellular networks. Thus, the 5G era is emerging to quench the increasing demand for network capacity, to manage explosive growth of traffic patterns and to face the challenges caused by the proliferation of versatile applications and high-end devices. In this paper, we make a broad survey on 5G cellular network architecture and some of the promising key technologies such as cloud RAN (Radio Access Network), Software-Defined Networking (SDN), Network Function Virtualization (NFV) and modulation formats. Finally, this ground-breaking survey highlights major existing research issues and possible future research directions in the next new era of mobile wireless networks.

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22

Fayad, Abdulhalim, Tibor Cinkler, Jacek Rak, and Manish Jha. "Design of Cost-Efficient Optical Fronthaul for 5G/6G Networks: An Optimization Perspective." Sensors 22, no. 23 (December 1, 2022): 9394. http://dx.doi.org/10.3390/s22239394.

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Currently, 5G and the forthcoming 6G mobile communication systems are the most promising cellular generations expected to beat the growing hunger for bandwidth and enable the fully connected world presented by the Internet of Everything (IoE). The cloud radio access network (CRAN) has been proposed as a promising architecture for meeting the needs and goals of 5G/6G (5G and beyond) networks. Nevertheless, the provisioning of cost-efficient connections between a large number of remote radio heads (RRHs) in the cell sites and the baseband unit (BBU) pool in the central location, known as the fronthaul, has emerged as a new challenge. Many wired and wireless solutions have been proposed to address this bottleneck. Specifically, optical technologies presented by passive optical networks (PONs) are introduced as the best suitable solution for 5G and beyond network fronthaul due to their properties of providing high capacity and low latency connections. We considered time and wavelength division multiplexed passive optical networks (TWDM-PONs) as a fronthaul for 5G and beyond. Taking that into consideration, in this paper, we propose an integer linear program (ILP) that results in the optimal optical fronthaul deployment while minimizing the total cost of 5G and beyond instances. However, for larger network instances, solving the ILP problem becomes unscalable and time-consuming. To address that, we developed two heuristic-based algorithms (the K-means clustering algorithm and the one based on the genetic algorithm—GA). We evaluated the suitability of our proposed ILP and heuristic algorithms in simulations by utilizing them to plan different network instances (dense and sparse).

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23

Park, Jeonghun, and Robert W. Heath. "Low Complexity Antenna Selection for Low Target Rate Users in Dense Cloud Radio Access Networks." IEEE Transactions on Wireless Communications 15, no. 9 (September 2016): 6022–32. http://dx.doi.org/10.1109/twc.2016.2577580.

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24

Klinkowski, Mirosław, and Marek Jaworski. "Planning of Optical Connections in 5G Packet-Optical xHaul Access Network." Applied Sciences 12, no. 3 (January 22, 2022): 1146. http://dx.doi.org/10.3390/app12031146.

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One of the main challenges in dense 5G radio access networks (RANs) is provisioning of low-cost connectivity between a large number of antennas, located at remote sites, and a central site (hub) in which baseband processing functions are performed. Packet-switched Ethernet and wavelength division multiplexing (WDM) are two principal transport network technologies enabling the reduction of the demand for direct optical fiber connections between the antennas and the hub. Whereas Ethernet allows for statistical multiplexing of multiple xHaul (fronthaul/midhaul/backhaul) flows and their aggregation in a high-capacity transmission link, WDM makes it possible to establish a number of such links (using different wavelengths) in a single optical fiber. Additional savings in the amount of fibers required can be achieved by means of optical add-drop multiplexers (OADMs) that allow for obtaining access to unused wavelengths by intermediate remote nodes, whenever the capacity on the WDM system is not fully utilized by the end remote node. In this work, we focus on the problem of planning optimal fiber connections, including the placement of OADMs for a set of wavelength demands at remote sites, with the aim of minimizing the amount of fibers used in a packet-optical xHaul access network carrying 5G traffic. We consider a passive WDM system in which the maximum transmission distance, estimated using an optical power-budget model, depends on the number of OADMs that are present on the transmission path. To formulate and solve the optimization problem, we make use of integer linear programming (ILP). We apply the ILP model in network analysis. In particular, by means of numerical experiments performed for two different network topologies, we study the impact of traffic load (in terms of the number of requested wavelengths) and optical multiplexer loss on the number of transmission paths that have to be established in the network. Obtained results show that the savings in fiber connections of up to 65% can be achieved in a packet-optical xHaul network if OADMs are used when compared to the scenario without OADMs.

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25

Fokin, Grigoriy A. "5G NETWORK POSITIONING AND STATISTIC MODELS FOR ITS AC-CURACY EVALUATION." T-Comm 14, no. 12 (2020): 4–17. http://dx.doi.org/10.36724/2072-8735-2020-14-12-4-17.

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The relevance of issues of network positioning in general, and methods of assessing accuracy in particular, is due to the fact that technologies for location estimation by means of infrastructure of deployed and projected mobile radio communication networks have received a new impetus for development. This is due to a number of objective factors in recent years, which are the result of ongoing evolution at the next stage of the transition to 5G networks. If in the networks of previous generations 2G-4G geolocation was an optional service, which developed mainly according to the requirements of emergency services and law enforcement, as well as in scenarios when signals from global navigation satellite systems (GNSS) were unavailable, then for a promising 5G digital ecosystem, network positioning can rightfully be stated as a separate area of research and development. The arguments for this statement are at least two circumstances. First, in recent years, a wide range of geoinformation services has been developed, which are impossible and / or inappropriate to solve exclusively by GNSS systems. It is also indicative that in the latest specifications of the 3GPP partner project, among others, there were explicit requirements for the accuracy and availability of network positioning services, as well as a description of all possible geolocation scenarios with an accuracy of one meter. Secondly, the analysis of foreign sources in recent years has shown that the so-called concept of communication organization based on LAC (Location Aware Communication) positioning data has been developed, according to which location awareness can be used at different levels of the OSI model for improving the efficiency of building and operating radio stations as part of ultra-dense 5G radio access networks. In this paper, positioning scenarios in 5G networks are systematized, as well as probabilistic models and methods for assessing the accuracy of geolocation in relation to the problems of location estimation in 5G networks. In the first part of this paper, scenarios of network positioning for the 5G ecosystem are presented, in particular: specifics of organizing radio communications based on location data are presented; the development trends of positioning technologies in 5G networks are formulated; analyzes 3GPP requirements for positioning in 5G networks. In the second part of this work, the results of the development and software implementation of tools for probabilistic assessment and visualization of positioning accuracy along the scattering ellipse are presented.

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26

Fokin, G., and A. Vladyko. "The Vehicles Positioning in Ultra-Dense 5G/V2X Radio Access Networks Using the Extended Kalman Filter." Proceedings of Telecommunication Universities 6, no. 4 (December 2020): 45–59. http://dx.doi.org/10.31854/1813-324x-2020-6-4-45-59.

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This work is devoted to the study of mathematical models of vehicle positioning in ultra-dense V2X / 5G radio access networks using the extended Kalman filter. Based on the study of the probability of line-of-sight availability in the conditions of ultra-dense distribution of reference radio access stations and vehicles, as well as existing mathematical prototype positioning models, a new simulation model for constructing the trajectory of a vehicle has been developed to assess compliance with the requirements for the accuracy of coordinate assessment on the example of the scenario of priority passage of intersections. The simulation model implements the procedures for collecting primary angle and rangefinder measurements by reference stations received from the vehicle for subsequent secondary processing using the extended Kalman filter, as a result of which the vehicle trajectory is built in real time. In contrast to the existing prototype models, the simulation model developed in this work makes it possible to assess compliance with the specified requirements and other specifications depending on the current conditions of line-of-sight availability, as well as the accuracy of collecting primary angle measurements determined by the antenna array installed on the support device. The results of simulation are consistent with the known estimates of prototype models and confirm the possibility of achieving an accuracy of up to 1 m for a traffic control scenario with an error in determining the angle of arrival of a signal of 2 °.

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Pham, Congduc, and Muhammad Ehsan. "Dense Deployment of LoRa Networks: Expectations and Limits of Channel Activity Detection and Capture Effect for Radio Channel Access." Sensors 21, no. 3 (January 26, 2021): 825. http://dx.doi.org/10.3390/s21030825.

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Анотація:

With worldwide deployment of LoRa/LoRaWAN LPWAN networks in a large variety of applications, it is crucial to improve the robustness of LoRa channel access which is largely ALOHA-like to support environments with higher node density. This article presents extensive experiments on LoRa Channel Activity Detection and Capture Effect property in order to better understand how a competition-based channel access mechanisms can be optimized for LoRa LPWAN radio technology. In the light of these experimentation results, the contribution continues by identifying design guidelines for a channel access mechanism in LoRa and by proposing a channel access method with a lightweight collision avoidance mechanism that can operate without a reliable Clear Channel Assessment procedure. The proposed channel access mechanism has been implemented and preliminary tests show promising capabilities in increasing the Packet Delivery Rate in dense configurations.

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Khalid, Waqas, and Heejung Yu. "Spatial–Temporal Sensing and Utilization in Full Duplex Spectrum-Heterogeneous Cognitive Radio Networks for the Internet of Things." Sensors 19, no. 6 (March 23, 2019): 1441. http://dx.doi.org/10.3390/s19061441.

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Анотація:

The continuous growth of interconnected devices in the Internet of Things (IoT) presents a challenge in terms of network resources. Cognitive radio (CR) is a promising technology thatcan address the IoT spectral demands by enabling an opportunistic spectrum access (OSA) scheme. The application of full duplex (FD) radios in spectrum sensing enables secondary users (SUs) to perform sensing and transmission simultaneously, and improves the utilization of the spectrum. However, random and dense distributions of FD-enabled SU transmitters (FD-SU TXs) with sensing capabilities in small-cell CR-IoT environments poses new challenges, and creates heterogeneous environments with different spectral opportunities. In this paper, we propose a spatial and temporal spectral-hole sensing framework for FD-SU TXs deployed in CR-IoT spectrum-heterogeneous environment. Incorporating the proposed sensing model, we present the analytical formulation and an evaluation of a utilization of spectrum (UoS) scheme for FD-SU TXs present at different spatialpositions. The numerical results are evaluated under different network and sensing parameters to examine the sensitivities of different parameters. It is demonstrated that self-interference, primary user activity level, and the sensing outcomes in spatial and temporal domains have a significant influence on the utilization performance of spectrum.

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Lorincz, Josip, and Zvonimir Klarin. "How Trend of Increasing Data Volume Affects the Energy Efficiency of 5G Networks." Sensors 22, no. 1 (December 30, 2021): 255. http://dx.doi.org/10.3390/s22010255.

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Анотація:

As the rapid growth of mobile users and Internet-of-Everything devices will continue in the upcoming decade, more and more network capacity will be needed to accommodate such a constant increase in data volumes (DVs). To satisfy such a vast DV increase, the implementation of the fifth-generation (5G) and future sixth-generation (6G) mobile networks will be based on heterogeneous networks (HetNets) composed of macro base stations (BSs) dedicated to ensuring basic signal coverage and capacity, and small BSs dedicated to satisfying capacity for increased DVs at locations of traffic hotspots. An approach that can accommodate constantly increasing DVs is based on adding additional capacity in the network through the deployment of new BSs as DV increases. Such an approach represents an implementation challenge to mobile network operators (MNOs), which is reflected in the increased power consumption of the radio access part of the mobile network and degradation of network energy efficiency (EE). In this study, the impact of the expected increase of DVs through the 2020s on the EE of the 5G radio access network (RAN) was analyzed by using standardized data and coverage EE metrics. An analysis was performed for five different macro and small 5G BS implementation and operation scenarios and for rural, urban, dense-urban and indoor-hotspot device density classes (areas). The results of analyses reveal a strong influence of increasing DV trends on standardized data and coverage EE metrics of 5G HetNets. For every device density class characterized with increased DVs, we here elaborate on the process of achieving the best and worse combination of data and coverage EE metrics for each of the analyzed 5G BSs deployment and operation approaches. This elaboration is further extended on the analyses of the impact of 5G RAN instant power consumption and 5G RAN yearly energy consumption on values of standardized EE metrics. The presented analyses can serve as a reference in the selection of the most appropriate 5G BS deployment and operation approach, which will simultaneously ensure the transfer of permanently increasing DVs in a specific device density class and the highest possible levels of data and coverage EE metrics.

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Dash, Biswajit Kumar, and Jun Peng. "Zigbee Wireless Sensor Networks: Performance Study in an Apartment-Based Indoor Environment." Journal of Computer Networks and Communications 2022 (August 5, 2022): 1–14. http://dx.doi.org/10.1155/2022/2144702.

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Анотація:

Zigbee is a very popular technology for Internet of things (IoT) networks mainly because of its low power consumption and low-cost features. It shares the unlicensed 2.4 GHz Industrial, Scientific, and Medical (ISM) radio band with other wireless networks such as Wi-Fi. Usually, Zigbee and Wi-Fi networks coexist in indoor environments for their respective applications. Hence, the coexistence introduces interference for both types of networks lowering the performance of the networks, but Zigbee suffers more significant performance losses because of its lower transmission power than Wi-Fi. Since the number of IoT devices is increasing at an unprecedented rate due to numerous emerging applications and thus making the indoor environments very populous, the peaceful coexistence between Zigbee and Wi-Fi networks in proximity becomes an important research study. For this purpose, this paper presents a comprehensive performance study of a Zigbee network in the presence of a Wi-Fi interference network in a real-life apartment-based indoor environment where Wi-Fi access points of dense neighbors exist. The experiments were done in a XBee module-based Zigbee network for measuring the received signal strength indicator (RSSI), packet drop rate (PDR), and loopback throughput with and without nearby Wi-Fi traffic introduced on purpose. Various networking parameters such as the operating channels, the distances between Zigbee devices and Wi-Fi devices, the transmit timeout of Zigbee packets, and the transmission power of the Zigbee transmitter have been used in the experiments to study the network performance. Our results show that in the deployment of IoT networks in a smart home, radio interference from neighboring homes would not be an important factor, but serious considerations may need to be taken inside the same home. The experimental observations of this paper can serve as a good reference study for Zigbee network deployments in real indoor environments, particularly when interference sources are present in proximity.

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Desrochers, André, Junior Tremblay, Yves Aubry, Dominique Chabot, Paul Pace, and David Bird. "Estimating Wildlife Tag Location Errors from a VHF Receiver Mounted on a Drone." Drones 2, no. 4 (December 11, 2018): 44. http://dx.doi.org/10.3390/drones2040044.

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Анотація:

Recent studies have demonstrated the high potential of drones as tools to facilitate wildlife radio-tracking in rugged, difficult-to-access terrain. Without estimates of accuracy, however, data obtained from receivers attached to drones will be of limited use. We estimated transmitter location errors from a drone-borne VHF (very high frequency) receiver in a hilly and dense boreal forest in southern Québec, Canada. Transmitters and the drone-borne receiver were part of the Motus radio-tracking system, a collaborative network designed to study animal movements at local to continental scales. We placed five transmitters at fixed locations, 1–2 m above ground, and flew a quadrotor drone over them along linear segments, at distances to transmitters ranging from 20 m to 534 m. Signal strength was highest with transmitters with antennae pointing upwards, and lowest with transmitters with horizontal antennae. Based on drone positions with maximum signal strength, mean location error was 134 m (range 44–278 m, n = 17). Estimating peak signal strength against drone GPS coordinates with quadratic, least-squares regressions led to lower location error (mean = 94 m, range 15–275 m, n = 10) but with frequent loss of data due to statistical estimation problems. We conclude that accuracy in this system was insufficient for high-precision purposes such as finding nests. However, in the absence of a dense array of fixed receivers, the use of drone-borne Motus receivers may be a cost-effective way to augment the quantity and quality of data, relative to deploying personnel in difficult-to-access terrain.

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Chih-Lin, I., Shuangfeng Han, Zhikun Xu, Qi Sun, and Zhengang Pan. "5G: rethink mobile communications for 2020+." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, no. 2062 (March 6, 2016): 20140432. http://dx.doi.org/10.1098/rsta.2014.0432.

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The 5G network is anticipated to meet the challenging requirements of mobile traffic in the 2020s, which are characterized by super high data rate, low latency, high mobility, high energy efficiency and high traffic density. This paper provides an overview of China Mobile’s 5G vision and potential solutions. Three key characteristics of 5G are analysed, i.e. super fast, soft and green. The main 5G R&D themes are further elaborated, which include five fundamental rethinkings of the traditional design methodologies. The 5G network design considerations are also discussed, with cloud radio access network, ultra-dense network, software defined network and network function virtualization examined as key potential solutions towards a green and soft 5G network. The paradigm shift to user-centric network operation from the traditional cell-centric operation is also investigated, where the decoupled downlink and uplink, control and data, and adaptive multiple connections provide sufficient means to achieve a user-centric 5G network with ‘no more cells’. The software defined air interface is investigated under a uniform framework and can adaptively adapt the parameters to well satisfy various requirements in different 5G scenarios.

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33

Fokin, Grigoriy, and Dmitriy Volgushev. "Model for Interference Evaluation in 5G Millimeter-Wave Ultra-Dense Network with Location-Aware Beamforming." Information 14, no. 1 (January 9, 2023): 40. http://dx.doi.org/10.3390/info14010040.

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Location-Aware Beamforming (LAB) in Ultra-Dense Networks (UDN) is a breakthrough technology for 5G New Radio (NR) and Beyond 5G (B5G) millimeter wave (mmWave) communication. Directional links with narrow antenna half-power beamwidth (HPBW) and massive multiple-input multiple-output (mMIMO) processing systems allows to increase transmitter and receiver gains and thus facilitates to overcome high path loss in mmWave. Well known problem of pencil beamforming (BF) is in construction of precoding vectors at the transmitter and combining vectors at the receiver during directional link establishing and its maintaining. It is complicated by huge antenna array (AA) size and required channel state information (CSI) exchange, which is time consuming for vehicle user equipment (UE). Knowledge of transmitter and receiver location, UE or gNodeB (gNB), could significantly alleviate directional link establishment and space division multiple access (SDMA) implementation. Background of SDMA is in efficient maintenance of affordable level of interference, and the purpose of this research is in signal-to-interference ratio (SIR) evaluation in various 5G UDN scenarios with LAB. The method, used to evaluate SIR, is link level simulation, and results are obtained from publicly released open-source simulator. Contribution of research includes substantiation of allowable UE density, working with LAB. Practical implications include recommendations on terrestrial and angular separation of two UE in 5G UDN scenarios.

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Farooq, Muhammad Shoaib, Rana Muhammad Nadir, Furqan Rustam, Soojung Hur, Yongwan Park, and Imran Ashraf. "Nested Bee Hive: A Conceptual Multilayer Architecture for 6G in Futuristic Sustainable Smart Cities." Sensors 22, no. 16 (August 9, 2022): 5950. http://dx.doi.org/10.3390/s22165950.

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Анотація:

Several smart city ideas are introduced to manage various problems caused by overpopulation, but the futuristic smart city is a concept based on dense and artificial-intelligence-centric cities. Thus, massive device connectivity with huge data traffic is expected in the future where communication networks are expected to provide ubiquity, high quality of service, and on-demand content for a large number of interconnected devices. The sixth-generation (6G) network is considered the problem-solving network of futuristic cities, with huge bandwidth and low latency. The expected 6G of the radio access network is based on terahertz (THz) waves with the capability of carrying up to one terabit per second (Tbps). THz waves have the capability of carrying a large amount of data but these waves have several drawbacks, such as short-range and atmospheric attenuation. Hence, these problems can introduce complications and hamper the performance of the 6G network. This study envisions futuristic smart cities using 6G and proposes a conceptual terrestrial network (TN) architecture for 6G. The nested Bee Hive is a scalable multilayer architecture designed to meet the needs of futuristic smart cities. Moreover, we designed the multilayer network infrastructure while considering the expectations from a network of futuristic smart cities and the complications of THz waves. Extensive simulations are performed using different pathfinding algorithms in the 3D multilayer domain to evaluate the performance of the proposed architecture and set the dynamics of futuristic communication of 6G.

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35

Fokin, G., and A. Vladyko. "Vehicles Positioning with the Fusion of Time of Arrival, Angle of Arrival and Inertial Measurements in the Extended Kalman Filter." Proceedings of Telecommunication Universities 7, no. 2 (June 30, 2021): 51–67. http://dx.doi.org/10.31854/1813-324x-2021-7-2-51-67.

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Анотація:

This work is devoted to the study of models and methods for improving posi-tioning accuracy in ultra-dense V2X/5G radio access networks for vehicles during maneuvers by combining range and angle primary measurements with measurements of inertial navigation systems in the extended Kalman filter. Onboard platformless inertial navigation system is represented by three-axis accelerometer and gyroscope modules. Integration of primary inertial measurements of acceleration and angular velocity with primary radio measurements of range and angle is carried out by converting the inertial coordinate system of the accelerometer and gyroscope into coordinate system of vehicle using quaternions. Secondary processing of inertial and radio measurements is carried out in the extended Kalman filter. The integration results show an increase in the accuracy of estimating the trajectory of a vehicle from several meters to one meter when turning at an inter-section.

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Amrallah, Amr, Ehab Mahmoud Mohamed, Gia Khanh Tran, and Kei Sakaguchi. "Enhanced Dynamic Spectrum Access in UAV Wireless Networks for Post-Disaster Area Surveillance System: A Multi-Player Multi-Armed Bandit Approach." Sensors 21, no. 23 (November 25, 2021): 7855. http://dx.doi.org/10.3390/s21237855.

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Анотація:

Modern wireless networks are notorious for being very dense, uncoordinated, and selfish, especially with greedy user needs. This leads to a critical scarcity problem in spectrum resources. The Dynamic Spectrum Access system (DSA) is considered a promising solution for this scarcity problem. With the aid of Unmanned Aerial Vehicles (UAVs), a post-disaster surveillance system is implemented using Cognitive Radio Network (CRN). UAVs are distributed in the disaster area to capture live images of the damaged area and send them to the disaster management center. CRN enables UAVs to utilize a portion of the spectrum of the Electronic Toll Collection (ETC) gates operating in the same area. In this paper, a joint transmission power selection, data-rate maximization, and interference mitigation problem is addressed. Considering all these conflicting parameters, this problem is investigated as a budget-constrained multi-player multi-armed bandit (MAB) problem. The whole process is done in a decentralized manner, where no information is exchanged between UAVs. To achieve this, two power-budget-aware PBA-MAB) algorithms, namely upper confidence bound (PBA-UCB (MAB) algorithm and Thompson sampling (PBA-TS) algorithm, were proposed to realize the selection of the transmission power value efficiently. The proposed PBA-MAB algorithms show outstanding performance over random power value selection in terms of achievable data rate.

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Diamantoulakis, Panagiotis D., Vasilis K. Papanikolaou, and George K. Karagiannidis. "Optimization of Ultra-Dense Wireless Powered Networks." Sensors 21, no. 7 (March 30, 2021): 2390. http://dx.doi.org/10.3390/s21072390.

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Анотація:

The internet-of-things (IoT) is expected to have a transformative impact in several different domains, including energy management in smart grids, manufacturing, transportation, smart cities and communities, smart food and farming, and healthcare. To this direction, the maintenance cost of IoT deployments has been identified as one of the main challenges, which is directly related to energy efficiency and autonomy of IoT solutions. In order to increase the energy sustainability of next-generation IoT, wireless power transfer (WPT) emerged as a promising technology; however, its effectiveness is hindered as the distance between the base station and the wireless powered IoT devices increases. To counter this effect, decentralized approaches based on the use of distributed densely deployed remote radio heads (RRHs) can be utilized to diminish the distance between the transmitting and the receiving nodes. A trade-off ensues from the use of RRHs as power beacons (PBs) or access points (APs) that enable either energy transfer during downlink or information reception during uplink, respectively. To balance this trade-off, in this work, the maximization of the ergodic rate in ultra-dense wireless powered networks is investigated. In more detail, three different protocols are introduced, optimized, and compared to each other: density splitting, time splitting, and hybrid time and density splitting, which are based on the optimization of the portion of the number of RRHs that are employed as PBs or APs at a specific time instance. Additionally, two different policies are taken into account regarding the PBs’ power constraint. The formulated problems that correspond to the combination of the proposed protocols with each of the two considered power constraint policies are optimally solved by using convex optimization tools and closed-form solutions are derived that result to useful insights. Finally, numerical results are provided, which illustrate the ergodic rate achieved by each of the proposed protocols and offer interesting conclusions regarding their comparison, which are directly linked to design guidelines and the required capital and operational expenses.

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Cha, Kainan, Anil Ramachandran, and Sarangapani Jagannathan. "Adaptive and Probabilistic Power Control Algorithms for RFID Reader Networks." International Journal of Distributed Sensor Networks 4, no. 4 (October 1, 2008): 347–68. http://dx.doi.org/10.1080/15501320701344107.

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Анотація:

In radio frequency identification (RFID) systems, the detection range and read rates will suffer from interference among high power reading devices. This problem grows severely and degrades system performance in dense RFID networks. Consequently, medium access protocols (MAC) protocols are needed for such networks to assess and provide access to the channel so that tags can be read accurately. In this paper, we investigate a suite of feasible power control schemes to ensure overall coverage area of the system while maintaining a desired read rate. The power control scheme and MAC protocol dynamically adjusts the RFID reader power output in response to the interference level seen during tag reading and acceptable signal-to-noise ratio (SNR). We present novel distributed adaptive power control (DAPC) and probabilistic power control (PPC) as two possible solutions. A suitable back off scheme is also added with DAPC to improve coverage. Both the methodology and implementation of the schemes are presented, simulated, compared, and discussed for further work.

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Zhang, Lu, Zefeng Chen, Hongqi Zhang, Zuomin Yang, Yixin Wu, Xiongbin Yu, Xiaodan Pang, Vjaceslavs Bobrovs, Oskars Ozolins, and Xianbin Yu. "Hybrid fiber–THz fronthaul supporting up to 16384-QAM-OFDM with the delta-sigma modulation." Optics Letters 47, no. 17 (August 17, 2022): 4307. http://dx.doi.org/10.1364/ol.466080.

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Анотація:

With the progress of high-capacity radio access networks, ultra-dense small cells are rapidly being deployed in urban areas. As a result, the deployment of a large number of optical fibers in urban areas becomes a severe issue. In this Letter, we propose a hybrid fiber–terahertz (THz) mobile fronthaul system supporting flexible and high-order wireless signal transmission with the delta-sigma modulation. The photonic THz transmission is used as the seamless extension of fiber-based fronthaul in small cells. A 20-Gbit/s digital fiber–THz fronthaul system is experimentally demonstrated to validate the proposed scheme, with 10-km optical fiber transmission and 300-GHz wireless relay. Carrier aggregation of up to 10 40-MHz and 60-MHz 5G-new radio (5G-NR) channels at the radio carrier frequency of 3.9 GHz is reported. The design of quantization noise suppressed delta-sigma modulation enables the system to transmit orthogonal frequency division multiplexing (OFDM) modulation up to 16384 order quadrate amplitude modulation (QAM) mapping with the error vector magnitude (EVM) below 0.5%.

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Kolyadenko, Yu Yu, and N. A. Chursanov. "ANALYSIS OF INDICATORS OF ELECTROMAGNETIC COMPATIBILITY OF COMMUNICATION NETWORKS 5 G." Radio Electronics, Computer Science, Control, no. 3 (October 5, 2021): 7–16. http://dx.doi.org/10.15588/1607-3274-2021-3-1.

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Анотація:

Context. The next generation 5G / IMT-2020 technology, like any new technology, brings its own specific features to all aspects of the practice of its application. One of these particularly important aspects is electromagnetic compatibility. At the stage of preparation for the introduction of 5G radio networks, it is necessary to take early measures to effectively assess the EMC conditions for these networks based on a thorough analysis of the features of 5G technology, and by correctly and accurately assessing these conditions, successfully ensure the electromagnetic compatibility of radio equipment of new networks. Objective. The purpose of this work is to analyze the electromagnetic compatibility of the 5G communication network. Method. An analysis of the main features of the 5G radio interface provides an indication of the expected features of the EMC assessment procedures for these networks. These features mainly relate to taking into account the total interference from the network with its special architecture and dynamics of changes, the choice of new loss models (channel models) for spatially distributed radiation of multidimensional MIMO antennas and a heterogeneous signal propagation medium, as well as taking into account the spectral properties of new signal shapes and character radiation with new non-orthogonal radio access methods.For EMC analysis, a model of signal attenuation in millimeter-wave radio channels was used, taking into account attenuation of radio waves in free space; loss of energy of radio waves when propagating through rains; attenuation of a millimeter wave signal when propagating through the leaves of trees; attenuation of signals when passing through dense obstacles (buildings, structures, etc.). Results. The analysis of attenuation of the millimeter-wave signal in free space from the intensity of precipitation is carried out at various values of optical visibility. The analysis of the attenuation of the millimeter-wave signal from the distance when the signal propagates through obstacles in the form of walls at various values of the wall thickness is carried out. The analysis of the attenuation of the millimeter-wave signal from the depth of the leaf layer is carried out; it covers the signal propagation at different values of the carrier frequency. The analysis of the value of the power of the millimeter-wave signal at the input of the receiver on the intensity of precipitation is carried out at various values of optical visibility. The analysis of the value of the power of the millimeter-wave signal at the input of the receiver versus the distance when the signal propagates through obstacles in the form of walls at various values of the wall thickness is carried out. The analysis of the power value of the millimeter-wave signal at the receiver input from the depth of the leaf layer is carried out, overlaps the signal propagation at various values of the carrier frequency. Conclusions. The conducted studies of EMC indicators allow us to give recommendations on the application of 5G technology in specific practical situations.

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Koudouridis, Georgios P., Henrik Lundqvist, Hamid Reza Karimi, and Gunnar Karlsson. "A quantitative analysis of the throughput gains and the energy efficiency of multi-radio transmission diversity in dense access networks." Telecommunication Systems 59, no. 1 (December 24, 2014): 145–68. http://dx.doi.org/10.1007/s11235-014-9889-0.

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42

Djibo, Moumouni, Wend Yam Serge Boris Ouedraogo, Ali Doumounia, Serge Roland Sanou, Moumouni Sawadogo, Idrissa Guira, Nicolas Koné, Christian Chwala, Harald Kunstmann, and François Zougmoré. "Towards Innovative Solutions for Monitoring Precipitation in Poorly Instrumented Regions: Real-Time System for Collecting Power Levels of Microwave Links of Mobile Phone Operators for Rainfall Quantification in Burkina Faso." Applied System Innovation 6, no. 1 (December 27, 2022): 4. http://dx.doi.org/10.3390/asi6010004.

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Анотація:

Since the 1990s, mobile telecommunication networks have gradually become denser around the world. Nowadays, large parts of their backhaul network consist of commercial microwave links (CMLs). Since CML signals are attenuated by rainfall, the exploitation of records of this attenuation is an innovative and an inexpensive solution for precipitation monitoring purposes. Performance data from mobile operators’ networks are crucial for the implementation of this technology. Therefore, a real-time system for collecting and storing CML power levels from the mobile phone operator “Telecel Faso” in Burkina Faso has been implemented. This new acquisition system, which uses the Simple Network Management Protocol (SNMP), can simultaneously record the transmitted and received power levels from all the CMLs to which it has access, with a time resolution of one minute. Installed at “Laboratoire des Matériaux et Environnement de l’Université Joseph KI-ZERBO (Burkina Faso)”, this acquisition system is dynamic and has gradually grown from eight, in 2019, to more than 1000 radio links of Telecel Faso’s network in 2021. The system covers the capital Ouagadougou and the main cities of Burkina Faso (Bobo Dioulasso, Ouahigouya, Koudougou, and Kaya) as well as the axes connecting Ouagadougou to these cities.

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Dai, Peng, Yuan Yang, Manyi Wang, and Ruqiang Yan. "Combination of DNN and Improved KNN for Indoor Location Fingerprinting." Wireless Communications and Mobile Computing 2019 (March 6, 2019): 1–9. http://dx.doi.org/10.1155/2019/4283857.

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Анотація:

Fingerprinting based on Wi-Fi Received Signal Strength Indicator (RSSI) has been widely studied in recent years for indoor localization. While current algorithms related to RSSI Fingerprinting show a much lower accuracy than multilateration based on time of arrival or the angle of arrival techniques, they highly depend on the number of access points (APs) and fingerprinting training phase. In this paper, we present an integrated method by combining the deep neural network (DNN) with improved K-Nearest Neighbor (KNN) algorithm for indoor location fingerprinting. The improved KNN is realized by boosting the weights on K-nearest neighbors according to the number of matching access points. This will overcome the limitation of the original KNN algorithm on ignoring the influence of the neighboring points, which directly affect localization accuracy. The DNN algorithm is first used to classify the Wi-Fi RSSI Fingerprinting dataset. Then these possible locations in a certain class are also classified by the improved KNN algorithm to determine the final position. The proposed method is validated inside a room within about 13⁎9 m2. To examine its performance, the presented method has been compared with some classical algorithms, i.e., the random forest (RF) based algorithm, the KNN based algorithm, the support vector machine (SVM) based algorithm, the decision tree (DT) based algorithm, etc. Our real-world experiment results indicate that the proposed method is less dependent on the dense of access points and indoor radio propagation interference. Furthermore, our method can provide some preliminary guidelines for the design of indoor Wi-Fi test bed.

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44

Piyare, Rajeev, Amy Murphy, Michele Magno, and Luca Benini. "On-Demand LoRa: Asynchronous TDMA for Energy Efficient and Low Latency Communication in IoT." Sensors 18, no. 11 (November 1, 2018): 3718. http://dx.doi.org/10.3390/s18113718.

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Energy efficiency is crucial in the design of battery-powered end devices, such as smart sensors for the Internet of Things applications. Wireless communication between these distributed smart devices consumes significant energy, and even more when data need to reach several kilometers in distance. Low-power and long-range communication technologies such as LoRaWAN are becoming popular in IoT applications. However, LoRaWAN has drawbacks in terms of (i) data latency; (ii) limited control over the end devices by the gateway; and (iii) high rate of packet collisions in a dense network. To overcome these drawbacks, we present an energy-efficient network architecture and a high-efficiency on-demand time-division multiple access (TDMA) communication protocol for IoT improving both the energy efficiency and the latency of standard LoRa networks. We combine the capabilities of short-range wake-up radios to achieve ultra-low power states and asynchronous communication together with the long-range connectivity of LoRa. The proposed approach still works with the standard LoRa protocol, but improves performance with an on-demand TDMA. Thanks to the proposed network and protocol, we achieve a packet delivery ratio of 100% by eliminating the possibility of packet collisions. The network also achieves a round-trip latency on the order of milliseconds with sensing devices dissipating less than 46 mJ when active and 1.83 μW during periods of inactivity and can last up to three years on a 1200-mAh lithium polymer battery.

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45

Verdecia-Peña, Randy, and José I. Alonso. "MIMO Channel Estimation in an SDR Platform for Evaluation of D&F Relay Nodes." Electronics 9, no. 10 (October 12, 2020): 1662. http://dx.doi.org/10.3390/electronics9101662.

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Relay Nodes (RNs) have received special attention as a radio access technology which can overcome channel fading and improve the channel capacity in high-speed and dense vehicle environments. RNs have been the object of standardization by the 3GPP; however, this process has not been accompanied by the development of hardware that allows for evaluation of the advantages of RNs. Software Defined Radio (SDR) has emerged as a promising technology to implement the concept of RNs at low cost. In this paper, a detailed study of the MIMO wireless channel between an evolved Node-B (eNB) and an RN is carried out. The developed algorithms are implemented in an SDR platform for Decode-and-Forward (D&F) relay node evaluation, resulting in significant improvements of its capabilities on the MIMO channel. A pilot symbol-assisted channel estimation algorithm based on combinations of the Least-Squares (LS) technique and Bi-Cubic (BCI), Bi-Linear (BLI), and Bi-Nearest Neighbors (BNNI) interpolation methods is considered. Furthermore, the Minimum Mean Square Error (MMSE) and Zero-Forcing (ZF) equalization schemes are studied. In the tests conducted, Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) scenarios are considered, demonstrating the capabilities of the developed platform. The performance measurements using different modulation schemes are compared under the same conditions. The simulation results show that the LS technique together with the BCI and MMSE methods performed the best among all evaluated channel estimation and equalization algorithms, in terms of the Error Vector Magnitude (EVM) performance of the received Resource Grid (RG). Furthermore, we show that the Bit Error Rate (BER) and throughput of the core network increase when using the 2 × 2 MIMO technique.

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46

Mukhtar, Alaa M., Rashid A. Saeed, Rania A. Mokhtar, Elmustafa Sayed Ali, and Hesham Alhumyani. "Performance Evaluation of Downlink Coordinated Multipoint Joint Transmission under Heavy IoT Traffic Load." Wireless Communications and Mobile Computing 2022 (January 6, 2022): 1–16. http://dx.doi.org/10.1155/2022/6837780.

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Emerging 5G network cellular promotes key empowering techniques for pervasive IoT. Evolving 5G-IoT scenarios and basic services like reality augmented, high dense streaming of videos, unmanned vehicles, e-health, and intelligent environments services have a pervasive existence now. These services generate heavy loads and need high capacity, bandwidth, data rate, throughput, and low latency. Taking all these requirements into consideration, internet of things (IoT) networks have provided global transformation in the context of big data innovation and bring many problematic issues in terms of uplink and downlink (DL) connectivity and traffic load. These comprise coordinated multipoint processing (CoMP), carriers’ aggregation (CA), joint transmissions (JTs), massive multi-inputs multi-outputs (MIMO), machine-type communications, centralized radios access networks (CRAN), and many others. CoMP is one of the most significant technical enhancements added to release 11 that can be implemented in heterogonous networks implementation approaches and the homogenous networks’ topologies. However, in a massive 5G-IoT device scenario with heavy traffic load, most cell edge IoT users are severely suffering from intercell interference (ICI), where the users have poor signal, lower data rates, and limited QoS. This work is aimed at addressing this problematic issue by proposing two types of DL-JT-CoMP techniques in 5G-IoT that are compliant with release 18. Downlink JT-CoMP with two homogeneous network CoMP deployment scenarios is considered and evaluated. The scenarios used are IoT intrasite and intersite CoMP, which performance evaluated using downlink system-level simulator for long-term evolution-advanced (LTE-A) and 5G. Numerical simulation scenarios were results under high dense scenario—with IoT heavy traffic load which shows that intersite CoMP has better empirical cumulative distribution function (ECDF) of average UE throughput than intrasite CoMP approximately 4%, inter-site CoMP has better ECDF of average user entity (UE) spectral efficiency than intrasite CoMP almost 10%, and intersite CoMP has approximately same ECDF of average signal interference noise ratio (SINR) as intrasite CoMP and intersite CoMP has better fairness index than intrasite CoMP by 5%. The fairness index decreases when the users’ number increase since the competition among users is higher.

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47

Blanc, Sara. "Event-Driven Data Gathering in Pure Asynchronous Multi-Hop Underwater Acoustic Sensor Networks." Sensors 20, no. 5 (March 4, 2020): 1407. http://dx.doi.org/10.3390/s20051407.

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In underwater acoustic modem design, pure asynchrony can contribute to improved wake-up coordination, thus avoiding energy-inefficient synchronization mechanisms. Nodes are designed with a pre-receptor and an acoustically adapted Radio Frequency Identification system, which wakes up the node when it receives an external tone. The facts that no synchronism protocol is necessary and that the time between waking up and packet reception is narrow make pure asynchronism highly efficient for energy saving. However, handshaking in the Medium Control Access layer must be adapted to maintain the premise of pure asynchronism. This paper explores different models to carry out this type of adaptation, comparing them via simulation in ns-3. Moreover, because energy saving is highly important to data gathering driven by underwater vehicles, where nodes can spend long periods without connection, this paper is focused on multi-hop topologies. When a vehicle appears in a 3D scenario, it is expected to gather as much information as possible in the minimum amount of time. Vehicle appearance is the event that triggers the gathering process, not only from the nearest nodes but from every node in the 3D volume. Therefore, this paper assumes, as a requirement, a topology of at least three hops. The results show that classic handshaking will perform better than tone reservation because hidden nodes annulate the positive effect of channel reservation. However, in highly dense networks, a combination model with polling will shorten the gathering time.

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48

Arigye, Wilford, Qiaolin Pu, Mu Zhou, Waqas Khalid, and Muhammad Junaid Tahir. "RSSI Fingerprint Height Based Empirical Model Prediction for Smart Indoor Localization." Sensors 22, no. 23 (November 22, 2022): 9054. http://dx.doi.org/10.3390/s22239054.

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Smart indoor living advances in the recent decade, such as home indoor localization and positioning, has seen a significant need for low-cost localization systems based on freely available resources such as Received Signal Strength Indicator by the dense deployment of Wireless Local Area Networks (WLAN). The off-the-shelf user equipment (UE’s) available at an affordable price across the globe are well equipped with the functionality to scan the radio access network for hearable single strength; in complex indoor environments, multiple signals can be received at a particular reference point with no consideration of the height of the transmitter and possible broadcasting coverage. Most effective fingerprinting algorithm solutions require specialized labor, are time-consuming to carry out site surveys, training of the data, big data analysis, and in most cases, additional hardware requirements relatively increase energy consumption and cost, not forgetting that in case of changes in the indoor environment will highly affect the fingerprint due to interferences. This paper experimentally evaluates and proposes a novel technique for Received Signal Indicator (RSSI) distance prediction, leveraging transceiver height, and Fresnel ranging in a complex indoor environment to better suit the path loss of RSSI at a particular Reference Point (RP) and time, which further contributes greatly to indoor localization. The experimentation in different complex indoor environments of the corridor and office lab during work hours to ascertain real-life and time feasibility shows that the technique’s accuracy is greatly improved in the office room and the corridor, achieving lower average prediction errors at low-cost than the comparison prediction algorithms. Compared with the conventional prediction techniques, for example, with Access Point 1 (AP1), the proposed Height Dependence Path–Loss (HEM) model at 0 dBm error attains a confidence probability of 10.98%, higher than the 2.65% for the distance dependence of Path–Loss New Empirical Model (NEM), 4.2% for the Multi-Wall dependence on Path-Loss (MWM) model, and 0% for the Conventional one-slope Path-Loss (OSM) model, respectively. Online localization, amongst the hearable APs, it is seen the proposed HEM fingerprint localization based on the proposed HEM prediction model attains a confidence probability of 31% at 3 m, 55% at 6 m, 78% at 9 m, outperforming the NEM with 26%, 43%, 62%, 62%, the MWM with 23%, 43%, 66%, respectively. The robustness of the HEM fingerprint using diverse predicted test samples by the NEM and MWM models indicates better localization of 13% than comparison fingerprints.

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Celaya-Echarri, Mikel, Leyre Azpilicueta, Fidel Alejandro Rodríguez-Corbo, Peio Lopez-Iturri, Victoria Ramos, Mohammad Alibakhshikenari, Raed M. Shubair, and Francisco Falcone. "Towards Environmental RF-EMF Assessment of mmWave High-Node Density Complex Heterogeneous Environments." Sensors 21, no. 24 (December 16, 2021): 8419. http://dx.doi.org/10.3390/s21248419.

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The densification of multiple wireless communication systems that coexist nowadays, as well as the 5G new generation cellular systems advent towards the millimeter wave (mmWave) frequency range, give rise to complex context-aware scenarios with high-node density heterogeneous networks. In this work, a radiofrequency electromagnetic field (RF-EMF) exposure assessment from an empirical and modeling approach for a large, complex indoor setting with high node density and traffic is presented. For that purpose, an intensive and comprehensive in-depth RF-EMF E-field characterization study is provided in a public library study case, considering dense personal mobile communications (5G FR2 @28 GHz) and wireless 802.11ay (@60 GHz) data access services on the mmWave frequency range. By means of an enhanced in-house deterministic 3D ray launching (3D-RL) simulation tool for RF-EMF exposure assessment, different complex heterogenous scenarios of high complexity are assessed in realistic operation conditions, considering different user distributions and densities. The use of directive antennas and MIMO beamforming techniques, as well as all the corresponding features in terms of radio wave propagation, such as the body shielding effect, dispersive material properties of obstacles, the impact of the distribution of scatterers and the associated electromagnetic propagation phenomena, are considered for simulation. Discussion regarding the contribution and impact of the coexistence of multiple heterogeneous networks and services is presented, verifying compliance with the current established international regulation limits with exposure levels far below the aforementioned limits. Finally, the proposed simulation technique is validated with a complete empirical campaign of measurements, showing good agreement. In consequence, the obtained datasets and simulation estimations, along with the proposed RF-EMF simulation tool, could be a reference approach for the design, deployment and exposure assessment of the current and future wireless communication technologies on the mmWave spectrum, where massive high-node density heterogeneous networks are expected.

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50

Singh, P. "Heterogeneous Cloud Radio Access Network." International Journal of Computer Sciences and Engineering 5, no. 9 (September 2017): 46–51. http://dx.doi.org/10.26438/ijcse/v5i9.4651.

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