scholarly journals 3D Deployment of Unmanned Aerial Vehicle-Base Station Assisting Ground-Base Station

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Khaled F. Hayajneh ◽  
Khaled Bani-Hani ◽  
Hazim Shakhatreh ◽  
Muhammad Anan ◽  
Ahmad Sawalmeh
Keyword(s):  
Base Station ◽  
Path Model ◽  
Base Stations ◽  
Three Dimension ◽  
Available Bandwidth ◽  
Special Event ◽  
Proposed Model ◽  
Aerial Vehicle ◽  
The Impact

Unmanned aerial vehicles (UAVs), also named as drones, have become a modern model to provide a quick wireless communication infrastructure. They have been used when conventional base stations’ capacity is suffering in some extreme cases such as congestion inside the cell or a special event. This paper proposes an efficient three-dimension (3D) placement of a single UAV-assisted wireless network in such cases. Our proposed model assists the ground base station (GBS) using the UAV to serve arbitrary distributed users considering the impact of the obstacle blockage over the well-known air-to-ground (A2G) path model. This work is aimed at optimizing the percentage of available bandwidth that must be provided to the UAV in order to maximize the number of served users. In addition, it finds the 3D placement of the UAV base station (UAVBS) that maximizes the number of served users, each with maximum quality-of-service (QoS). The exhaustive search and particle swarm optimization (PSO) algorithms are used to find the problem’s solution.

scholarly journals Performance of Base Stations in Railway Digital Radio Communication Networks

2021 ◽  
Vol 19 (2) ◽  
pp. 41-48
Author(s):  
Yu. V. Nemtsov ◽  
I. V. Seryogin ◽  
P. I. Volnov
Keyword(s):  
Communication Network ◽  
Communication Networks ◽  
Base Station ◽  
Base Stations ◽  
Radio Communication ◽  
Radio Communications ◽  
Digital Radio ◽  
Cargo Transportation ◽  
Assess Quality

Base station (BS) is a terminal device of a radio communication network, while railway radio communications play an important role in ensuring safety of passenger and cargo transportation.A proposed method for calculating the performance of base stations in railway digital radio communication networks is intended to calculate for the BS the probabilities of being in certain state.BS was decomposed and such functional elements as circuit groups and a radio frequency path were identified, as well as the central module ensuring the exchange of information with elements of this BS and with other BSs. A detailed study of each element has increased accuracy of the proposed method. Following the Markov model, BS is presented as a system in which all possible states are considered. Models for BS with two and three circuit groups have been constructed. The parameters of each functional element of the model can be obtained through observation over a certain period. The solution of the system of equations for each of the models presented in the article will allow obtaining the values of the system being in a certain state. The obtained characteristics can be used to calculate the reliability of the entire radio communication network, and then to assess quality of service provided to the users of this network.Conclusions are made about the possibilities of using the obtained models when designing new railway communication networks and when calculating quality indices of existing ones. The proposed models can be applied not only to railway radio communication networks but also to mobile communication networks of commercial operators. 

A Game Theoretic Framework for Green HetNets Using D2D Traffic Offload and Renewable Energy Powered Base Stations

2017 ◽  
pp. 679-711
Author(s):  
Elias Yaacoub ◽  
Hakim Ghazzai ◽  
Mohamed-Slim Alouini
Keyword(s):  
Renewable Energy ◽  
Renewable Energy Sources ◽  
Nash Bargaining Solution ◽  
Base Station ◽  
Base Stations ◽  
Nash Bargaining ◽  
Bargaining Solution ◽  
Green Communications ◽  
Game Theoretic

This chapter investigates the interplay between cooperative device-to-device (D2D) communications and green communications in LTE heterogeneous networks (HetNets). Two game theoretic concepts are studied and analyzed in order to perform dynamic HetNet base station (BS) on/off switching. The first approach is a coalition-based method whereas the second is based on the Nash bargaining solution. Afterwards, a method for coupling the BS on/off switching approach with D2D collaborative communications is presented and shown to lead to increased energy efficiency. The savings are additionally increased when a portion of the small cell BSs in a HetNet are powered by renewable energy sources. Different utility functions, modeling the game theoretic framework governing the energy consumption balance between the cellular network and the mobile terminals (MTs), are proposed and compared, and their impact on MT quality of service (QoS) is analyzed.

Congestion Avoidance and Delay Minimization in Energy Aware Routing of Dynamic ieee 802.11s WMN

2016 ◽  
Vol 7 (1) ◽  
pp. 85-112 ◽  
Author(s):  
S.P. Shiva Prakash ◽  
T.N. Nagabhushan ◽  
Kirill Krinkin
Keyword(s):  
Mesh Networks ◽  
Cluster Head ◽  
High Energy ◽  
Base Station ◽  
Base Stations ◽  
Cluster Head Selection ◽  
Slot Allocation ◽  
Proposed Model ◽  
Slot Scheduling ◽  
Link Duration

Minimization of delay in collecting the data at any base stations is one of the major concerns in cluster based Wireless Mesh Networks. several researches have proposed algorithms to control congestion considering static nature of a node. Mobility of a node results in high congestion due to frequent link breakages and high energy consumption due to re-establishment of route during routing process. Hence, the authors consider dynamic nodes with single hop inside the static cluster. The proposed model includes four modules namely, Cluster head selection, slot allocation, slot scheduling and data collection process. the cluster head selection is based on the maximum energy, number of links and link duration. Slot allocation is based on the available energy () and the required energy (). Slot scheduling is carried out based on the link duration. Data at the base station will be collected as they are scheduled. Model is tested using Network Simulator-3 (NS3) and results indicate that the proposed model achieves least delay besides reducing the congestion compared to the existing methods.

scholarly journals A Multistep Approach for Managing the Risks of Software Requirements Volatility

2016 ◽  
Vol 9 (1) ◽  
pp. 101
Author(s):  
Nedhal A. Al-Saiyd
Keyword(s):  
Software Requirements ◽  
Software Project ◽  
Font Size ◽  
Software Usability ◽  
Proposed Model ◽  
Requirements Volatility ◽  
And Control ◽  
Requirement Changes ◽  
The Impact

<p><span style="font-size: 10.5pt; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;" lang="EN-US">Software is changed continuously in order to respond to different users and business needs. Requirements are changed dynamically to improve software usability and increase its value, but requirement volatility sometimes cause failures for many projects because of inadequate understanding of the changing causes and the consequences of these changes. This research highlights the importance of managing requirement changes, classify them, and control the impact risks of requirement volatility on software project. The proposed model is designed based on software requirements risks factors and how to reduce their impacts. Generally, requirements changing is considered as a difficult, costly and time-consumed task, and consequently it is too important to study the inter-relationships between the changes and their impacts on the other phases of software system. The good understanding of the changing causes and their consequences can improve and support requirements management process and also lead successfully to the predicted goals of changes. The high quality of the requirements influences the success of a software project during software development and maintenance processes.</span></p>

scholarly journals Dynamic access class barring and relay assisted radio resource allocation methods for cellular M2M networks

2021 ◽  
Author(s):  
Lilatul Ferdouse
Keyword(s):  
Resource Allocation ◽  
Load Balancing ◽  
Transmission Rate ◽  
Random Access ◽  
Base Station ◽  
Base Stations ◽  
Radio Resource Allocation ◽  
Radio Resource ◽  
Selection Probability ◽  
The Impact

Cellular based M2M systems generate massive number of access requests which create congestion in the cellular network. The contention-based random access procedures are designed for cellular networks which cannot accommodate a large number of M2M traffic. Moreover, M2M systems share same radio resources with cellular users. Resource allocation problem becomes a challenging issue in cellular M2M systems. In this thesis, we address these two problems by analyzing a contention-based slotted Aloha random access procedure for M2M networks using different performance metrics. The impact of massive M2M traffic over cellular traffic is studied based on different arrival rate, random access opportunity and throughput. An analytical model of selecting a base station (eNB) along with load balancing is developed. Finally, two methods have been presented and evaluated with M2M traffic. First one is dynamic access class barring method which controls RAN level congestion by selecting an appropriate eNB and applying load balancing method. Second one is relay-assisted radio resource allocation method which maximizes the sum throughput of the system by utilizing the available radio resource blocks and relay nodes to the MTC systems. Numerical results show that frame transmission rate influences the selection probability of the base stations. Moreover, the dynamic access class barring parameter along with frame transmission rate improve the overall throughput and access success probability among base stations as well as avoid overload situation in a particular base station.

scholarly journals Performance Analysis of Backhaul-Aware User Association in 5G Ultradense Heterogeneous Networks

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Junpeng Yu ◽  
Hongtao Zhang ◽  
Yuqing Chen ◽  
Yaduan Ruan
Keyword(s):  
Heterogeneous Networks ◽  
Association Scheme ◽  
Coverage Probability ◽  
Network Performance ◽  
Performance Metrics ◽  
Density Ratio ◽  
Base Station ◽  
Base Stations ◽  
User Association ◽  
The Impact

In 5G ultradense heterogeneous networks, wireless backhaul, as one of the important base station (BS) resources that affect user services, has attracted more and more attention. However, a user would access to the BS which is the nearest for the user based on the conventional user association scheme, which constrains the network performance improvement due to the limited backhaul capacity. In this paper, using backhaul-aware user association scheme, semiclosed expressions of network performance metrics are derived in ultradense heterogeneous networks, including coverage probability, rate coverage, and network delay. Specifically, all possible access and backhaul links within the user connectable range of BSs and anchor base stations (A-BSs) are considered to minimize the analytical results of outage probability. The outage for the user occurs only when the access link or backhaul link which forms the link combination with the optimal performance is failure. Furthermore, the theoretical analysis and numerical results evaluate the impact of the fraction of A-BSs and the BS-to-user density ratio on network performance metric to seek for a more reasonable deployment of BSs in the practical scenario. The simulation results show that the coverage probability of backhaul-aware user association scheme is improved significantly by about 2× compared to that of the conventional user association scheme when backhaul is constrained.

Application of electronic total stations for survey of metal towers designs of cellular communications

2017 ◽  
Vol 922 (4) ◽  
pp. 2-6
Author(s):  
A.V. Vinogradov ◽  
O.N. Pushchak
Keyword(s):  
Base Station ◽  
Base Stations ◽  
Cellular Communications ◽  
Operating Characteristics ◽  
Simple Method ◽  
Control Error ◽  
Cellular Metal ◽  
Improve Accuracy ◽  
Independent Observations

The availability and stability of cellular communication can be achieved with areas coverage by base stations. Base station cellular (metal tower) is a complex and massive engineering structure which is usually installed on different buildings. Weight of tower with equipment exceeds 1000 kg. For security purposes of objects with installed cellular base stations you need constantly determine the operating characteristics of towers. One of the important characteristics is the deviation of the tower from the vertical. In the regulations for the operation of towers various ways of determining the deviation of the tower from the vertical are discussed. In the instructions it is proposed to determine the deviation of the tower based on observations with three or four starting points, between which there must be mutual visibility. After all dimensions processing we will receive a deviation of the tower from the vertical. The paper proposes a more simple method of determining deviations of the tower from the vertical with the use of electronic total station. The software of the instrument will improve the quality of the work. Measurements are performed from one point in topocentric coordinates system. Independent observations from a different point improve accuracy and serve as a control. Error of the results does not exceed 5–7 mm.

scholarly journals The Impact of Antenna Height on 3D-MIMO Channel: a Ray Launching Based Analysis

2017 ◽  
Author(s):  
Qi Hong ◽  
Jiliang Zhang ◽  
Hui Zheng ◽  
Hao Li ◽  
Haonan Hu ◽  
...  
Keyword(s):  
Channel Model ◽  
Elevation Angle ◽  
Base Station ◽  
Mimo Channel ◽  
Delay Spread ◽  
Three Dimension ◽  
Angle Of Arrival ◽  
3D Mimo ◽  
The Impact ◽  
Ray Launching

Three dimension (3D) Multi-input-multi-output (MIMO) scheme, which exploits another dimension of the spatial resource, is one of the enabling technologies for the next generation mobile communication. As the elevation angle in 3D-MIMO channel model might varies against the height of the base station transmit antenna, it has to be taken into account carefully. In this paper, the impact of antenna height on the channel characteristics of 3D MIMO channel is investigated by using the intelligent ray launching algorithm (IRLA). Three typical street scenarios, i.e., the straight street, the fork road and the cross road, are selected as benchmarks. On the basis of simulations, joint and marginal probability density functions (PDFs) of both the elevation angle of departure (EAoD) and the elevation angle of arrival (EAoA) are obtained. The elevation angle spread (AS) and the delay spread (DS) under various antenna heights are also discussed. Simulation results indicate that the PDFs of EAoD and EAoA vary characteristics under different street scenarios. Moreover, the minimum value of the DS can be achieved when the antenna height is half of the building height.

scholarly journals Stochastic Geometry Analysis of Downlink Spectral and Energy Efficiency in Ultradense Heterogeneous Cellular Networks

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Jiaqi Lei ◽  
Hongbin Chen ◽  
Feng Zhao
Keyword(s):  
Energy Efficiency ◽  
Cellular Networks ◽  
Stochastic Geometry ◽  
Density Ratio ◽  
Base Station ◽  
Small Cell ◽  
Base Stations ◽  
Heterogeneous Cellular Networks ◽  
Downlink Throughput ◽  
The Impact

The energy efficiency (EE) is a key metric of ultradense heterogeneous cellular networks (HCNs). Earlier works on the EE analysis of ultradense HCNs by using the stochastic geometry tool only focused on the impact of the base station density ratio and ignored the function of different tiers. In this paper, a two-tier ultradense HCN with small-cell base stations (SBSs) and user equipments (UEs) densely deployed in a traditional macrocell network is considered. Firstly, the performance of the ultradense HCN in terms of the association probability, average link spectral efficiency (SE), average downlink throughput, and average EE is theoretically analyzed by using the stochastic geometry tool. Then, the problem of maximizing the average EE while meeting minimum requirements of the average link SE and average downlink throughput experienced by UEs in macrocell and small-cell tiers is formulated. As it is difficult to obtain the explicit expression of average EE, impacts of the SBS density ratio and signal-to-interference-plus-noise ratio (SINR) threshold on the network performance are investigated through numerical simulations. Simulation results validate the accuracy of theoretical results and demonstrate that the maximum value of average EE can be achieved by optimizing the SBS density ratio and the SINR threshold.

scholarly journals Passive Method for Estimating Available Throughput for Autonomous Off-Peak Data Transfer

2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
Kozo Satoda ◽  
Eiji Takahashi ◽  
Takeo Onishi ◽  
Takayuki Suzuki ◽  
Daisuke Ohta ◽  
...  
Keyword(s):  
Mobile Networks ◽  
Data Transfer ◽  
Peak Load ◽  
Base Station ◽  
Base Stations ◽  
Recent Analysis ◽  
Data Traffic ◽  
End User ◽  
Lte Networks

Large demands for mobile traffic subject base stations to frequent short-term and sharp peak loads. Recent analysis of data traffic on commercial mobile networks reported that the traffic peaks can be reduced by an average of 40% without compromising the quality of experience provided to the end user, if a peak load can be shifted for at most 20 s. To reduce peak traffic, we previously proposed a method for off-peak data transfer, with which user equipment (UE) autonomously delays receiving data, and a peak load on a base station can be shifted. In terms of off-peak transfer of data, a significant problem is determining how each UE estimates available throughput. In this paper we propose a method of passively estimating available throughput of each UE. We evaluated the effectiveness of the proposed method through experiments on experimental and commercial LTE networks. The results indicate that our method obtains more than a 0.7 correlation between actual available throughput and estimated throughput.

Sign in / Sign up

Export Citation Format

Share Document