scholarly journals Performance Evaluation of Direct-Link Backhaul for UAV-Aided Emergency Networks

Sensors ◽  
2019 ◽  
Vol 19 (15) ◽  
pp. 3342 ◽  
Author(s):  
German Castellanos ◽  
Margot Deruyck ◽  
Luc Martens ◽  
Wout Joseph
Keyword(s):  
Network Performance ◽  
Access Network ◽  
Network Capacity ◽  
Base Stations ◽  
60 Ghz ◽  
City Center ◽  
Flight Height ◽  
Backhaul Networks ◽  
The City ◽  
Cell Base

Today’s wireless networks provide us reliable connectivity. However, if a disaster occurs, the whole network could be out of service and people cannot communicate. Using a fast deployable temporally network by mounting small cell base stations on unmanned aerial vehicles (UAVs) could solve the problem. Yet, this raises several challenges. We propose a capacity-deployment tool to design the backhaul network for UAV-aided networks and to evaluate the performance of the backhaul network in a realistic scenario in the city center of Ghent, Belgium. This tool assigns simultaneously resources to the ground users—access network—and to the backhaul network, taking into consideration backhaul capacity and power restrictions. We compare three types of backhaul scenarios using a 3.5 GHz link, 3.5 GHz with carrier aggregation (CA) and the 60 GHz band, considering three different types of drones. The results showed that an optimal UAV flight height (80 m) could satisfy both access and backhaul networks; however, full coverage was difficult to achieve. Finally, we discuss the influence of the flight height and the number of requesting users concerning the network performance and propose an optimal configuration and new mechanisms to improve the network capacity, based on realistic restrictions.

scholarly journals A ROF Access Network for Simultaneous Generation and Transmission Multiband Signals Based on Frequency Octupling and FWM Techniques

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Hui Zhou ◽  
Yunlong Shen ◽  
Ming Chen ◽  
Jun Cheng ◽  
Yuting Zeng
Keyword(s):  
Optical Filter ◽  
Access Network ◽  
Optical Amplifier ◽  
Base Stations ◽  
Frequency Interval ◽  
60 Ghz ◽  
Simultaneous Generation ◽  
Optical Signals ◽  
Tunable Optical Filter ◽  
Rf Signal

We report a radio-over-fiber (ROF) access network with multiple high-repetive frequency mm-wave signals generation utilizing a dual-parallel Mach-Zehnder modulator (DP-MZM) and an semiconductor optical amplifier (SOA) for multiple base stations (BSs). In the scheme, at the central station (CS), signal and pump with frequency interval of 8fRF are generated by properly adjusting the parameters of the DP-MZM. After FWM in a SOA, new converted optical signals are obtained. Two tones of the optical signals are selected by using tunable optical filter (TOF), which are then sent into a photodiode (PD) to generate multiple mm-wave signals with different frequencies (8fRF, 16fRF, and 24fRF) for different BSs. Based on the proposed scheme, the mm-wave signals with frequencies of 20, 40, and 60 GHz carrying 2.5 Gb/s signal by a 2.5GHz RF signal have been generated by numerical simulation. Simulation results show that the proposed ROF system architecture with multiple-frequency millimeter-wave signals generation serving multiple BSs can work well. This scheme can raise the capacity of ROF system, reduce the requirement of the repetitive frequency of the driven RF signal, and support multiple mm-wave wireless access for BSs.

scholarly journals A Request-Based Handover Strategy Using NDN for 5G

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Fan Jia ◽  
Xiaolin Zheng
Keyword(s):  
Optimal Allocation ◽  
Access Network ◽  
Base Stations ◽  
Network Selection ◽  
Allocation Of Resources ◽  
Selection Mechanism ◽  
Traffic Reduction ◽  
Access Network Selection ◽  
Caching Mechanism ◽  
Cell Base

With the developing of 5G, it is widely accepted that 5G will use a system architecture that supports the ultradense networks (UDN) deployments. In this architecture, a user will be covered by a large amount of small cell base stations (SBS) in 5G. However, selecting an SBS for handover is a great challenge. To address the challenge, the emerging content-oriented Named Data Networking (NDN) has attractive advantages, such as providing name-based routing. In this paper, a request-based handover strategy (RBHS) is presented to improve the user experience in performance and obtain the optimal allocation of resources, and a caching mechanism based on the users’ requests is introduced for it. The proposed caching mechanism and access network selection mechanism were validated utilizing ndnSIM. Simulation results demonstrate that our proposed strategy achieves around 30% higher cache hit rate and 20% more traffic reduction, compared with the access network selection based on SINR.

scholarly journals Heterogeneous Networks in 5g using Joint Path Selection and Rate Allocation Framework

2020 ◽  
Vol 9 (1) ◽  
pp. 509-512
Keyword(s):  
Learning Algorithm ◽  
Access Network ◽  
Path Selection ◽  
Base Stations ◽  
Average Output ◽  
Distributed Management ◽  
Transmission Strategy ◽  
Macro Cell ◽  
Radio Access ◽  
Cell Base

One of the major challenges in evolving wireless cellular networks whose return network is constrained by capability and heterogeneity (wired, wireless, and hybrid) is the design of distributed management mechanism. This study proposes a new method of managing wireless network interference with the ability to detect return network. The proposed approach helps Macro-cell User Equipment (MUE) to maximize its output using adjacent small cell base stations to maximize its uplink. Considering the radio access network and backhaul (possibly heterogeneous), this issue is represented as a non-cooperative game between MUE that attempts to maximize its compensation for delay levels. A new distributed learning algorithm is proposed to solve this problem, which uses the algorithm to autonomously choose the best uplink transmission strategy, provided a limited amount of available knowledge. The algorithm's convergence is demonstrated, and its output is studied. The simulation results show that, in comparison to the existing reference algorithm, The proposed approach has substantial efficiency benefits for various forms of backhaul in terms of average output and delay in MUE.

scholarly journals How Trend of Increasing Data Volume Affects the Energy Efficiency of 5G Networks

Sensors ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 255
Author(s):  
Josip Lorincz ◽  
Zonimir Klarin
Keyword(s):  
Energy Efficiency ◽  
Power Consumption ◽  
Mobile Networks ◽  
Access Network ◽  
Mobile Network ◽  
Network Capacity ◽  
Base Stations ◽  
Density Class ◽  
Radio Access ◽  
The Impact

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.

scholarly journals Development of the fourth generation radio network and forecasting of its coverage in the conditions of urban development

Connectivity ◽  
2021 ◽  
Vol 149 (1) ◽  
Author(s):  
L. V. Dakova ◽  
◽  
S. Yu. Dakov ◽  
R. V. Duzhyy ◽  
A. A. Zavaliy ◽  
...  
Keyword(s):  
Urban Development ◽  
Communication Systems ◽  
Network Performance ◽  
Network Planning ◽  
Network Capacity ◽  
Base Stations ◽  
Fourth Generation ◽  
Large Network ◽  
Radio Network ◽  
User Coverage

Here is an example of how the fourth generation of cellular networks is developing rapidly today. The traffic per subscriber is growing every month. Operators are forced to provide coverage and the necessary capacity by installing new base stations. Quality network planning can provide better network performance and reduce deployment and optimization costs. It is also important to use a planning and optimization tool to model network coverage and perform performance analysis. According to the results of many studies, the amount of data transmitted over wireless networks has been growing significantly recently. Buildings are obstacles to the signal over long distances, so for the same area in different types of terrain for quality coverage it is necessary to place a different number of base stations. In addition, it is necessary to take into account the peculiarities of the building, as signals from different base stations are an obstacle for each other. On the other hand, high population density requires a large network capacity to meet the needs for speed and number of simultaneously connected users. Traffic is projected to increase by 2024, due to the emergence of new video services and the growing popularity and involvement of the population in existing ones. LTE-Advanced provides the ability to deploy repeaters to increase network performance. In the context of cellular communication systems, an important aspect is radio network planning - the process of locating base stations, determining the frequency channels and radio parameters of a wireless communication system to provide sufficient coverage and connection capacity to ensure the required level of service quality. to the user. Coverage planning refers to a geographic area where the network must provide a signal with sufficient power to provide access to voice or packet services, and capacity planning determines the system’s ability to provide services to a given number of subscribers. The purpose of the article is to study the process of planning the fourth generation LTE network in terms of urban development, calculations and modeling of coverage.

scholarly journals Effect of Backhaul Technologies on 3G Network Performance: A Case Study of Ado-Ekiti

2021 ◽  
Vol 5 (3) ◽  
pp. 23-31
Author(s):  
S. T. Ayoola ◽  
Y. O. Olasoji ◽  
K. B. Adedeji ◽  
C. G. Olebu ◽  
S. A. Busari ◽  
...  
Keyword(s):  
Packet Loss ◽  
Network Performance ◽  
Asynchronous Transfer Mode ◽  
Access Network ◽  
Base Station ◽  
Base Stations ◽  
Third Generation ◽  
Maximum Throughput ◽  
3G Network ◽  
Average Maximum

In the past years, when wireless network improvement occurs from 1G/2G to third generation (3G), the rate in the use of real-time traffic oriented applications for voice, video and data increases. Consequently, the bandwidth to be backhauled from the cell site to the mobile switching center increases rapidly. 3G network is most prevalent in Nigeria with wide area of coverage. However, in recent times, poor subscribers’ mobile broadband experience is still the major challenge faced by many GSM operators. One of the major causes of this challenge is the use of wrong backhaul for radio access network (RAN). This lead to poor traffic throughput, high packet loss or frame loss at the cell edge. To overcome this challenge, the use of appropriate backhaul technology is crucial. Third Generation Partnership Program (3GPP) recommends the use of either asynchronous transfer mode (ATM) or internet protocol (IP) as the backhaul technologies for its RAN. This paper presents the performance analysis and the comparison of the ATM RAN and IP RAN backhaul technologies using six different 3G sites (with 3G base stations) located at Ado local government area of Ekiti State, Nigeria. The performance of each base station with different backhaul technology was evaluated in term of average maximum throughput per day. The effect of frame loss (for ATM RAN network) and packet loss (for IP RAN network) on traffic throughput were also analyzed. The comparison of the overall result analysis shows that the 3G base stations with IP-based RAN backhaul has better performance than the base station with ATM-based RAN backhaul.

Accuracy of On-site Consistent Origin-Destination Estimation Method for Measuring the Actual Numbers of Consumer Shop-around Movements within the City Center of Hanoi, Vietnam

2012 ◽  
Vol 42 (2) ◽  
pp. 439-455 ◽  
Author(s):  
Saburo SAITO ◽  
Tran Ngoc HUY ◽  
Masakuni IWAMI ◽  
Takahiro SATO ◽  
Kosuke YAMASHIRO ◽  
...  
Keyword(s):  
Estimation Method ◽  
City Center ◽  
The City

Urban Development Strategies of City Centers: The Case of Rafah City, Palestinian Territories

2014 ◽  
Vol 8 (3) ◽  
pp. 195
Author(s):  
Omar S. Asfour ◽  
Samar Abu Ghali
Keyword(s):  
Urban Development ◽  
Gaza Strip ◽  
Geographic Location ◽  
Development Strategies ◽  
Functional Requirements ◽  
City Center ◽  
Palestinian Territories ◽  
The Gaza Strip ◽  
The City ◽  
Commercial Center

City centers worldwide are perceived as essential parts of the city, where city memories are preserved and its identity is expressed. They are planned to satisfy the functional requirements and pleasurable qualities of the city. Under the accelerating urbanization of the modern city, several challenges face these centers including demographic, economic, and environmental challenges. This requires a continuous and incremental urban development process based on clear strategy and action plans. Thus, this study focuses on urban development strategies of city centers, with a focus on Rafah city located in the Gaza Strip, Palestinian Territories. The geographic location of this city near the Palestinian-Egyptian borders makes it a promising commercial city at local and regional levels. Thus, the current situation of Rafah city center has been analyzed, and several development strategies have been proposed. This has been done through a field survey based on observation and a questionnaire directed to city center users. It has been found that there is a great potential of Rafah city center to be developed as a commercial center. In this regard, several strategies and required actions have been proposed in the fields of transportation, environmental quality, shopping activities, investment opportunities, and visual perception.

Spatial and Temporal Differences in Weekday Travel Durations Between Private-for-Hire Transportation Services and Transit in the City Center

2021 ◽  
pp. 036119812110197
Author(s):  
Baxter Shandobil ◽  
Ty Lazarchik ◽  
Kelly Clifton
Keyword(s):  
Transportation Network ◽  
Central City ◽  
Temporal Analysis ◽  
Time Of Day ◽  
City Center ◽  
Transportation Services ◽  
Regulatory Frameworks ◽  
Transit Services ◽  
Level Information ◽  
The City

There is increasing evidence that ridehailing and other private-for-hire (PfH) services such as taxis and limousines are diverting trips from transit services. One question that arises is where and when PfH services are filling gaps in transit services and where they are competing with transit services that are publicly subsidized. Using weekday trip-level information for trips originating in or destined for the city center of Portland, OR from PfH transportation services (taxis, transportation network companies, limousines) and transit trip data collected from OpenTripPlanner, this study investigated the temporal and spatial differences in travel durations between actual PfH trips and comparable transit trips (the same origin–destination and time of day). This paper contributes to this question and to a growing body of research about the use of ridehailing and other on-demand services. Specifically, it provides a spatial and temporal analysis of the demand for PfH transportation using an actual census of trips for a given 2 week period. The comparison of trip durations of actual PfH trips to hypothetical transit trips for the same origin–destination pairs into or out of the central city gives insights for policy making around pricing and other regulatory frameworks that could be implemented in time and space.

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