scholarly journals Efficient Deployment of Multi-UAVs in Massively Crowded Events

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3640 ◽  
Author(s):  
Ahmad Sawalmeh ◽  
Noor Othman ◽  
Hazim Shakhatreh
Keyword(s):  
Circle Packing ◽  
Pso Algorithm ◽  
Base Station ◽  
Coverage Area ◽  
Transmit Power ◽  
Maximum Coverage ◽  
Coverage Density ◽  
Multiple Uavs ◽  
Different Shapes ◽  
Wireless Coverage

In this paper, the efficient 3D placement of UAV as an aerial base station in providing wireless coverage for users in a small and large coverage area is investigated. In the case of providing wireless coverage for outdoor and indoor users in a small area, the Particle Swarm Optimization (PSO) and K-means with Ternary Search (KTS) algorithms are invoked to find an efficient 3D location of a single UAV with the objective of minimizing its required transmit power. It was observed that a single UAV at the 3D location found using the PSO algorithm requires less transmit power, by a factor of 1/5 compared to that when using the KTS algorithm. In the case of providing wireless coverage for users in three different shapes of a large coverage area, namely square, rectangle and circular regions, the problems of finding an efficient placement of multiple UAVs equipped with a directional antenna are formulated with the objective to maximize the coverage area and coverage density using the Circle Packing Theory (CPT). Then, the UAV efficient altitude placement is formulated with the objective of minimizing its required transmit power. It is observed that the large number of UAVs does not necessarily result in the maximum coverage density. Based on the simulation results, the deployment of 16, 19 and 26 UAVs is capable of providing the maximum coverage density of 78.5%, 82.5% and 80.3% for the case of a square region with the dimensions of 2 km × 2 km, a rectangle region with the dimensions of 6 km × 1.8 km and a circular region with the radius of 1.125 km, respectively. These observations are obtained when the UAVs are located at the optimum altitude, where the required transmit power for each UAV is reasonably small.

scholarly journals Power-Efficient Wireless Coverage Using Minimum Number of UAVs

Sensors ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 223
Author(s):  
Ahmad Sawalmeh ◽  
Noor Shamsiah Othman ◽  
Guanxiong Liu ◽  
Abdallah Khreishah ◽  
Ali Alenezi ◽  
...  
Keyword(s):  
Clustering Algorithm ◽  
Circle Packing ◽  
Three Dimensional ◽  
Base Stations ◽  
Transmit Power ◽  
Power Efficient ◽  
User Coverage ◽  
Minimum Number ◽  
Wireless Coverage ◽  
Placement Algorithms

Unmanned aerial vehicles (UAVs) can be deployed as backup aerial base stations due to cellular outage either during or post natural disaster. In this paper, an approach involving multi-UAV three-dimensional (3D) deployment with power-efficient planning was proposed with the objective of minimizing the number of UAVs used to provide wireless coverage to all outdoor and indoor users that minimizes the required UAV transmit power and satisfies users’ required data rate. More specifically, the proposed algorithm iteratively invoked a clustering algorithm and an efficient UAV 3D placement algorithm, which aimed for maximum wireless coverage using the minimum number of UAVs while minimizing the required UAV transmit power. Two scenarios where users are uniformly and non-uniformly distributed were considered. The proposed algorithm that employed a Particle Swarm Optimization (PSO)-based clustering algorithm resulted in a lower number of UAVs needed to serve all users compared with that when a K-means clustering algorithm was employed. Furthermore, the proposed algorithm that iteratively invoked a PSO-based clustering algorithm and PSO-based efficient UAV 3D placement algorithms reduced the execution time by a factor of ≈1/17 and ≈1/79, respectively, compared to that when the Genetic Algorithm (GA)-based and Artificial Bees Colony (ABC)-based efficient UAV 3D placement algorithms were employed. For the uniform distribution scenario, it was observed that the proposed algorithm required six UAVs to ensure 100% user coverage, whilst the benchmarker algorithm that utilized Circle Packing Theory (CPT) required five UAVs but at the expense of 67% of coverage density.

scholarly journals Underwater Self Deployment of Wireless Sensors for Maximum Coverage and Connectivity using K-Means Clustering

2018 ◽  
Vol 7 (2.11) ◽  
pp. 5
Author(s):  
Gurjaspreet Kaur ◽  
Surinder Singh ◽  
Ramanpreet Kaur ◽  
Gaurav Garg
Keyword(s):  
Wireless Sensors ◽  
Euclidean Distance ◽  
Base Station ◽  
Sensor Nodes ◽  
Wireless Sensor ◽  
Network Coverage ◽  
Coverage Area ◽  
Maximum Coverage ◽  
3D Space ◽  
Main Emphasis

By virtue of abundant research being executed in terrestrial wireless sensor networks, we get enlightened about the different advantages of using wireless sensors and implemented these wireless sensors in underwater to probe the area below the sea for its various applications. The most crucial task in underwater 3D space is the node deployment such that sensors can cover the maximum area while simultaneously maintaining the connectivity with the base station. Due to the advantages of self deployment where no pre calculations and no human interventions are needed, we proposed a distributed move restricted self deployment underwater wireless sensor network. The main emphasis is on maximizing the coverage area by the sensor nodes and simultaneously maintaining the connectivity with the base station. Firstly, the maximum coverage has achieved by removing the interference between the sensor nodes which minimize the coverage overlap and thus more area can be covered which improves the network coverage. Then by using K-Means clustering, all the sensors nodes were divided into clusters, having one centroid for each cluster. Further all these centroids have been interconnected and then by finding the centroid which is nearest to the sink by Euclidean distance formula, we connect it to the sink.  

Analysis of the Effect of Tilting Antenna on the Coverage Area of ??the 4G LTE Network (Case Study of Trenggalek District)

2019 ◽  
Vol 9 (4) ◽  
pp. 43-48
Author(s):  
Rizal Aji Istantowi
Keyword(s):  
Base Station ◽  
Base Stations ◽  
Optimal Conditions ◽  
Coverage Area ◽  
Lte Networks ◽  
Lte Network ◽  
Big Cities ◽  
4G Lte ◽  
4G Lte Networks

4G LTE networks in big cities are already well available. Meanwhile, on small to medium-sized cities, the 4G LTE network is not evenly distributed and maximized. This study chooses the variable tilting antenna to the coverage area, because in sending information from a base station using an antenna. The average RSRP value (dBm) of the existing base station in the calculation with a distance of 200 m is -122.90 dBm, a distance of 500 m is -136.79 dBm, and a distance of 1000 m -147.30 dBm. Meanwhile, in the simulation with a distance of 200 m of -108.22 dBm, a distance of 500 m of -121.81 dBm, and a distance of 1000 m of -132.69 dBm. The coverage area value of the existing base station in the calculation is 5.29%, while in the simulation it is 11.18%. The average RSRP value (dBm) at optimal conditions for calculations at a distance of 200 m is -80.13 dBm, at a distance of 500 m is -94.03 dBm and at a distance of 1000 m is -104.56 dBm. Meanwhile, the simulation at a distance of 200 m is -98.09 dBm, at a distance of 500 m is -112.79 dBm and at a distance of 1000 m is -123.31 dBm. The value of the coverage area for the calculation is 20.32%, while for the simulation it is 15.01%. The current need for base stations in Trenggalek District that has been met is 68%.

scholarly journals Enhancement of WiMAX networks using OPNET modeler platform

2021 ◽  
Vol 23 (3) ◽  
pp. 1510
Author(s):  
Noor Nateq Alfaisaly ◽  
Suhad Qasim Naeem ◽  
Azhar Hussein Neama
Keyword(s):  
High Speed ◽  
Network Performance ◽  
Performance Metrics ◽  
Channel Model ◽  
Low Cost ◽  
Base Station ◽  
Multipath Channel ◽  
Coverage Area ◽  
Wimax Networks ◽  
Better Than

Worldwide interoperability microwave access (WiMAX) is an 802.16 wireless standard that delivers high speed, provides a data rate of 100 Mbps and a coverage area of 50 km. Voice over internet protocol (VoIP) is flexible and offers low-cost telephony for clients over IP. However, there are still many challenges that must be addressed to provide a stable and good quality voice connection over the internet. The performance of various parameters such as multipath channel model and bandwidth over the Star trajectoryWiMAX network were evaluated under a scenario consisting of four cells. Each cell contains one mobile and one base station. Network performance metrics such as throughput and MOS were used to evaluate the best performance of VoIP codecs. Performance was analyzed via OPNET program14.5. The result use of multipath channel model (disable) was better than using the model (ITU pedestrian A). The value of the throughput at 15 dB was approximately 1600 packet/sec, and at -1 dB was its value 1300 packet/se. According to data, the Multipath channel model of the disable type the value of the MOS was better than the ITU Pedestrian A type.

scholarly journals Macrocells-User Protected Interference-Aware Transmit Power Control for LTE-A Heterogeneous Networks

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Arbab Waheed Ahmad ◽  
Heekwon Yang ◽  
Gul Shahzad ◽  
Chankil Lee
Keyword(s):  
Power Control ◽  
Heterogeneous Networks ◽  
Small Cell ◽  
System Level ◽  
Small Cells ◽  
Control Technique ◽  
Coverage Area ◽  
Current Channel ◽  
Transmit Power ◽  
Transmit Power Control

In Long Term Evolution-Advanced (LTE-A) heterogeneous networks (HetNets), small cells are deployed within the coverage area of macrocells having 1 : 1 frequency reuse. The coexistence of small cells and a macrocell in the same frequency band poses cross-tier interference which causes outage for macrocells users and/or small cell users. To address this problem, in this paper, we propose two algorithms that consider the received interference level at the evolved NodeB (eNB) while allocating transmit power to the users. In the proposed algorithm, the transmit power of all users is updated according to the target and instantaneous signal-to-noise-plus-interference ratio (SINR) condition as long as the effective received interference at the serving eNB is below the given threshold. Otherwise, if the effective received interference at the eNB is greater than the threshold, the transmit power of small cell users is gradually reduced in order to guarantee the target SINR for all macrocells users, aiming for zero-outage for macrocells users at the cost of an increased outage ratio for small cell users. Further, in the second algorithm, the transmit power of all users is additionally controlled by the power headroom report that considers the current channel condition while updating the transmit power which results in the outage ratio decreasing for small cell users. The extensive system-level simulations show significant improvements in the average throughput and outage ratio when compared with the conventional transmit power control technique.

Fading Activities of Herbicidal Droplets Amended with Emulsifiable Spray Adjuvants on Cucurbitaceous Leaves

2018 ◽  
Vol 61 (6) ◽  
pp. 1881-1888
Author(s):  
Jeng-Liang Lin ◽  
Heping Zhu
Keyword(s):  
Weed Control ◽  
Droplet Size ◽  
Spray Deposition ◽  
Herbicide Application ◽  
Spray Droplet ◽  
Coverage Area ◽  
Maximum Coverage ◽  
Fading Time ◽  
Selection Of ◽  
Spray Adjuvants

Abstract. Understanding reactions of surfactant-amended droplets on difficult-to-wet weed surfaces could help develop application strategies to increase herbicide efficacy. Behaviors of herbicidal droplets containing different emulsifiable anti-evaporation spray adjuvants were investigated by characterizing 250 and 450 µm herbicidal droplet dispersion and fading time on cucurbitaceous leaves placed inside a 20°C chamber at 30% and 60% relative humidity (RH). Droplet maximum coverage area increased with droplet size but not with RH, while droplet fading time increased with both droplet size and RH. Despite 450 µm droplets having greater maximum coverage area than 250 µm droplets, the larger droplets had higher fading rates and lower ratios of maximum coverage area to droplet volume. Droplet maximum coverage area and fading time on leaves were affected by adding spray adjuvants to the herbicide-only solution. The Uptake surfactant was more effective than the other two surfactants (AntiEvap+BS1000 and Enhance) in increasing droplet maximum coverage area and fading time. Compared to the herbicide-only solution, addition of Uptake surfactant to the herbicide solution could increase maximum coverage area by 68% and 52% for 250 and 450 µm droplets, respectively, but addition of AntiEvap+BS1000 or Enhance surfactants did not show significant increase. Similarly, addition of Uptake surfactant to the herbicide-only solution increased droplet fading times by 11.1% and 13.2% at 30% and 60% RH, respectively, for 250 µm droplets and by 34.7% and 2.8% at 30% and 60% RH, respectively, for 450 µm droplets. In contrast, addition of AntiEvap+BS1000 surfactant reduced fading time, and addition of Enhance surfactant did not significantly affect fading time. Therefore, appropriate selection of spray adjuvants for herbicide applications could significantly influence droplet deposit behaviors on cucurbitaceous leaves, leading to improved effectiveness of weed control. Keywords: Herbicide application, Spray deposition, Spray droplet, Surfactant, Weed control.

scholarly journals Optimum Deployment of Multiple UAVs for Coverage Area Maximization in the Presence of Co-Channel Interference

IEEE Access ◽  
2019 ◽  
Vol 7 ◽  
pp. 85203-85212 ◽  
Author(s):  
Aziz A. Khuwaja ◽  
Gan Zheng ◽  
Yunfei Chen ◽  
Wei Feng
Keyword(s):  
Coverage Area ◽  
Multiple Uavs ◽  
Channel Interference
Sign in / Sign up

Export Citation Format

Share Document