Unmanned aerial vehicles (UAVs) have become very popular recently for both civil uses and potential commercial uses, such as law enforcement, crop survey, grocery delivery, and photographing, although they were mainly used for military purposes before. Researchers need the help of simulations when they design and test new protocols for UAV networks because simulations can be done for a network of a size
that a test bed can hardly approach. In the simulation of an UAV network it is important to choose a radio propagation model for the links in the network. We study the shadowing radio propagation model in this paper and compare it with the free space model, both of which are available in the ns2 network simulation package. We also show how the choice of the parameters of the shadowing model would impact on the
network performance of a UAV network.
Routing in Wireless Sensor Networks: Improved Energy Efficiency and Coverage ...CSCJournals
This paper proposes a new method for collecting distributed data in Wireless Sensor Networks (WSNs) that can improve the energy efficiency and network coverage; especially in remote areas. In multi-hop communication, sink nodes are responsible for collecting and forwarding data to base stations. The nodes that are located near a sink node usually deplete their battery faster than other nodes because they are responsible for aggregating the data from other sensor nodes. Several studies have proved the advantages of using mobile sink nodes to reduce energy consumption. Nonetheless, the need for compatible and efficient routing algorithms cannot be understated. Accordingly, a hybrid routing algorithm based on the Dijkstra�s and Rendezvous algorithms is proposed. To improve the energy efficiency and coverage, Energy Efficient Hybrid Unmanned Vehicle Based Routing Algorithm (E2HUV) is proposed to create a routing path for Unmanned Aerial Vehicles (UAVs) that can be used as mobile sinks in WSNs. Performance results show that the E2HUV algorithm offers better efficiency as compared to currently existing algorithms.
Secure data storage over distributed nodes in network through broadcast techn...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Broad-Spectrum Model for Sharing Analysis between IMTAdvanced Systems and FSS...IOSRJECE
An appraisal of orthogonal frequency division multiplexing (OFDM) accredited for IMT-Advanced has been well thought-out in this letter. Derivation of the power spectral density (PSD) produce new model which easily assess the interfering signal power that appears in the band of a victim system without a spectrum emission mask. Furthermore, the broad-spectrum investigative model (BIM) can assess the interference from the 4G systems into FSS systems, when transmit power is unallocated to some sub-carriers overlapping the band of the victim system. Closed form is derived to create the model.
Routing in Wireless Sensor Networks: Improved Energy Efficiency and Coverage ...CSCJournals
This paper proposes a new method for collecting distributed data in Wireless Sensor Networks (WSNs) that can improve the energy efficiency and network coverage; especially in remote areas. In multi-hop communication, sink nodes are responsible for collecting and forwarding data to base stations. The nodes that are located near a sink node usually deplete their battery faster than other nodes because they are responsible for aggregating the data from other sensor nodes. Several studies have proved the advantages of using mobile sink nodes to reduce energy consumption. Nonetheless, the need for compatible and efficient routing algorithms cannot be understated. Accordingly, a hybrid routing algorithm based on the Dijkstra�s and Rendezvous algorithms is proposed. To improve the energy efficiency and coverage, Energy Efficient Hybrid Unmanned Vehicle Based Routing Algorithm (E2HUV) is proposed to create a routing path for Unmanned Aerial Vehicles (UAVs) that can be used as mobile sinks in WSNs. Performance results show that the E2HUV algorithm offers better efficiency as compared to currently existing algorithms.
Secure data storage over distributed nodes in network through broadcast techn...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Broad-Spectrum Model for Sharing Analysis between IMTAdvanced Systems and FSS...IOSRJECE
An appraisal of orthogonal frequency division multiplexing (OFDM) accredited for IMT-Advanced has been well thought-out in this letter. Derivation of the power spectral density (PSD) produce new model which easily assess the interfering signal power that appears in the band of a victim system without a spectrum emission mask. Furthermore, the broad-spectrum investigative model (BIM) can assess the interference from the 4G systems into FSS systems, when transmit power is unallocated to some sub-carriers overlapping the band of the victim system. Closed form is derived to create the model.
Mobility and Propagation Models in Multi-hop Cognitive Radio Networksszhb
Cognitive radio networks allow unlicensed
(secondary) users to opportunistically utilize the idle
resource of a licensed network for communication
without affecting the quality of service being offered to
the primary or licensed users. This paper investigates
the effect of mobility on performance of multi-hop
cognitive radio network under various propagation
models. MPEG4 video; a bandwidth intensive traffic, is
tested over these network conditions for secondary
users and results are validated using NS2 simulations.
Performance metrics used for evaluation include
throughput, delay variations etc.
Design and Analysis of Broadband Elliptical Microstrip Patch Antenna for Wire...TELKOMNIKA JOURNAL
In this paper presents the design and manufacture of a new broadband elliptical patch antenna
with a microstrip feed line and optimum antenna parameters. The antenna dimension of
(30 × 21 × 1.6) 푚푚3 and fabricated on an FR-4 epoxy substrate having relative dielectric constant 휀푟=4.3,
loss tangent tan (δ)=0.002 and the feed line used has characteristic impedance of 50Ω.The designed
antenna has the capability of operating in the bandwidth (6.95-30.94) GHz and the gain (6.8) dBi. The
antenna performance was modified by inserting a slots in the ground plane to achieve impedance
bandwidth (when S11≤-10dB) and slots to patch to improve the gain. The modified antenna was designed
to be used for fifth generation (5G) mobile communication. The simulation results are obtained using CST
software.
A STRUCTURED DEEP NEURAL NETWORK FOR DATA-DRIVEN LOCALIZATION IN HIGH FREQUEN...IJCNCJournal
Next-generation wireless networks such as 5G and 802.11ad networks will use millimeter waves operating
at 28GHz, 38GHz, or higher frequencies to deliver unprecedentedly high data rates, e.g., 10 gigabits per
second. However, millimeter waves must be used directionally with narrow beams in order to overcome the
large attenuation due to their higher frequency. To achieve high data rates in a mobile setting,
communicating nodes need to align their beams dynamically, quickly, and in high resolution. We propose a
data-driven, deep neural network (DNN) approach to provide robust localization for beam alignment,
using a lower frequency spectrum (e.g., 2.4 GHz). The proposed DNN-based localization methods use the
angle of arrival derived from phase differences in the signal received at multiple antenna arrays to infer the
location of a mobile node. Our methods differ from others that use DNNs as a black box in that the
structure of our neural network model is tailored to address difficulties associated with the domain, such as
collinearity of the mobile node with antenna arrays, fading and multipath. We show that training our
models requires a small number of sample locations, such as 30 or fewer, making the proposed methods
practical. Our specific contributions are: (1) a structured DNN approach where the neural network
topology reflects the placement of antenna arrays, (2) a simulation platform for generating training and
evaluation data sets under multiple noise models, and (3) demonstration that our structured DNN approach
improves localization under noise by up to 25% over traditional off-the-shelf DNNs, and can achieve submeter
accuracy in a real-world experiment.
Propagation Path Loss Modeling and Outdoor Coverage Measurements Review in Mi...IJECEIAES
The global bandwidth inadequacy facing wireless carriers has motivated the exploration of the underutilized millimeter wave (mm-wave) frequency spectrum for future broadband cellular communication networks, and mmWave band is one of the promising candidates due to wide spectrum. This paper presents propagation path loss and outdoor coverage and link budget measurements for frequencies above 6 GHz (mm-wave bands) using directional horn antennas at the transmitter and omnidirectional antennas at the receiver. This work presents measurements showing the propagation time delay spread and path loss as a function of separation distance for different frequencies and antenna pointing angles for many types of real-world environments. The data presented here show that at 28 GHz, 38 GHz and 60 GHz, unobstructed Line of Site (LOS) channels obey free space propagation path loss while non-LOS (NLOS) channels have large multipath delay spreads and can utilize many different pointing angles to provide propagation links. At 60 GHz, there is more path loss and smaller delay spreads. Power delay profiles PDPs were measured at every individual pointing angle for each TX and RX location, and integrating each of the PDPs to obtain received power as a function of pointing angle. The result shows that the mean RMS delay spread varies between 7.2 ns and 74.4 ns for 60 GHz and 28 GHz respectively in NLOS scenario.
Enabling full-duplex in multiple access technique for 5G wireless networks ov...TELKOMNIKA JOURNAL
Nowadays, unmanned aerial vehicle (UAV) relays’assisted Internet of Things (IoT) systems provide facility in order to overcome the large scale fading between source and sink. The full-duplex scheme enables wireless network to provide higher spectrum efficient technology. This paper analyses performance of two users which are served by new emerging non-orthogonal multiple access (NOMA) technique. Exact outage probability of such two users are derived and checked via Monte-Carlo simulation. These analytical results provide guideline to design UAV in real application. This paper provides a comprehensive study to examine impact of interference, fixed power allocation factors to system performance.
ADAPTIVE RANDOM SPATIAL BASED CHANNEL ESTIMATION (ARSCE) FOR MILLIMETER WAVE ...IJCNCJournal
Millimeter-wave and mMIMO communications are the most essential success systems for next-generation wireless sensor networks to have enormous amounts of accessible throughput and spectrum. Through installing huge antenna arrays at the base station and performing coherent transceiver processing, mMIMO is a potential technology for enhancing the bandwidth efficiency of wireless sensor networks. The use of mmWave frequencies for mMIMO systems solves the problem of high path-loss through offering greater antenna gains. In this work, we provide a design with a random spatial sample structure that incorporates a totally random step before the analogue is received. It contains a totally random step before the analogue received signals are sent into the digital component of the HBF receiver. Adaptive random spatial based channel estimation (ARSCE) is proposed for channel session measurement collection, and an analogue combiner with valves has been used to estimate the signals at each receiving antenna. The proposed optimization problem formulation attempts to discover the orientations and gains of wideband channel routes. In addition, our proposed model has compared to various state-of-art techniques while considering error minimization.
Wideband Sensing for Cognitive Radio Systems in Heterogeneous Next Generation...CSCJournals
Mobile Next Generation Network (MNGN) is characterized as heterogeneous network where variety of access technologies are meant to coexist. Decisions on choosing an air interface that meets a particular need at a particular time will be shifted from the network’s side to (a more intelligent) user’s side. On top of that network operators and regularities have come to the realization that assigned spectrum bands are not utilized as they should be. Cognitive radio stands out as a candidate technology to address many emerging issues in MNGN such as capacity, quality of service and spectral efficiency. As a transmission strategy, cognitive radio systems depend greatly on sensing the radio environment. In this paper, we present a novel approach for interference characterization in cognitive radio networks based on wideband chirp signal. The results presented show that improved sensing accuracy is maintained at tolerable system complexity.
Efficient energy, cost reduction, and QoS based routing protocol for wireless...IJECEIAES
Recent developments and widespread in wireless sensor network have led to many routing protocols, many of these protocols consider the efficiency of energy as the ultimate factor to maximize the WSN lifetime. The quality of Service (QoS) requirements for different applications of wireless sensor networks has posed additional challenges. Imaging and data transmission needs both QoS aware routing and energy to ensure the efficient use of sensors. In this paper, we propose an Efficient, Energy-Aware, Least Cost, (ECQSR) quality of service routing protocol for sensor networks which can run efficiently with best-effort traffic processing. The protocol aims to maximize the lifetime of the network out of balancing energy consumption across multiple nodes, by using the concept of service differentiation, finding lower cost by finding the shortest path using nearest neighbor algorithm (NN), also put certain constraints on the delay of the path for real-time data from where link cost that captures energy nodes reserve, energy of the transmission, error rate and other parameters. The results show that the proposed protocol improves the network lifetime and low power consumption.
A Novel Routing Strategy Towards Achieving Ultra-Low End-to-End Latency in 6G...IJCNCJournal
Compared to 5G, 6G networks will demand even more ambitious reduction in endto-end latency for packet communication. Recent attempts at breaking the barrier of end-to-end millisecond latencies have focused on re-engineering networks using a hybrid approach consisting of an optical-fiber based backbone network architecture coupled with high-speed wireless networks to connect end-devices to the backbone network. In our approach, a wide area network (WAN) is considered with a high-speed optical fiber grid network as its backbone. After messages from a source node enter the backbone network through a local wireless network, these are delivered very fast to an access point in the backbone network closest to the destination node, followed by its transfer to the local wireless network for delivery to the destination node. We propose a novel routing strategy which is based on distributing the messages in the network in such a way that the average queuing delay of the messages through the backbone network is minimized, and also the route discovery time at each router in the backbone network is drastically reduced. Also, multiple messages destined towards a particular destination router in the backbone network are packed together to form a mailbag, allowing further reductions in processing overheads at intermediate routers and pipelining of mailbag formation and route discovery operations in each router. The performance of the proposed approach green based on these ideas has been theoretically analyzed and then simulated using the ns-3 simulator. Our results show that the average end-to-end latency is less than 380 µs (with only 46-79 µs within the backbone network under varying traffic conditions) for a 1 KB packet size, when using a 500 Gbps optical fiber based backbone network laid over a 15 Km × 15 Km area, a 50 Mbps uplink channel from the source to the backbone network, and a 1 Gbps downlink channel from the backbone network to the destination. The significant reduction in end-to-end latency as compared to existing routing solutions clearly demonstrates the potential of our proposed routing strategy for meeting the ultra-low latency requirements of current 5G and future 6G networks, particularly for mobile edge computing (MEC) application scenarios.
ADAPTIVE SENSOR SENSING RANGE TO MAXIMISE LIFETIME OF WIRELESS SENSOR NETWORK IJCNCJournal
Wireless Sensor Network (WSN) is commonly used to collect information from a remote area and one of the most important challenges associated with WSN is to monitor all targets in a given area while maximizing network lifetime. In wireless communication, energy consumption is proportional to the breadth of sensing range and path loss exponent. Hence, the energy consumption of communication can be minimized by varying the sensing range and decreasing the number of messages being sent. Sensing energy can be optimized by reducing the repeated coverage target. In this paper, an Adaptive Sensor Sensing Range (ASSR) technique is proposed to maximize the WSN Lifetime. This work considers a sensor network with an adaptive sensing range that are randomly deployed in the monitoring area. The sensor is adaptive in nature and can be modified in order to save power while achieving maximum time of monitoring to increase the lifetime of WSN network. The objective of ASSR is to find the best sensing range for each sensor to cover all targets in the network, which yields maximize the time of monitoring of all targets and eliminating double sensing for the same target. Experiments were conducted using an NS3 simulator to verify our proposed technique. Results show that ASSR is capable to improve the network lifetime by 20% as compared to other recent techniques in the case of a small network while achieving an 8% improvement for the case of a large networks.
Performance Enhancement in SU and MU MIMO-OFDM Technique for Wireless Communi...IJECEIAES
The consistent demand for higher data rates and need to send giant volumes of data while not compromising the quality of communication has led the development of a new generations of wireless systems. But range and data rate limitations are there in wireless devices. In an attempt to beat these limitations, Multi Input Multi Output (MIMO) systems will be used which also increase diversity and improve the bit error rate (BER) performance of wireless systems. They additionally increase the channel capacity, increase the transmitted data rate through spatial multiplexing, and/or reduce interference from other users. MIMO systems therefore create a promising communication system because of their high transmission rates without additional bandwidth or transmit power and robustness against multipath fading. This paper provides the overview of Multiuser MIMO system. A detailed review on how to increase performance of system and reduce the bit error rate (BER) in different fading environment e.g. Rayleigh fading, Rician fading, Nakagami fading, composite fading.
Magnetic resonance coupling for 5G WPT applicationsjournalBEEI
Inductive Wireless Power Transfer (IWPT) is the most popular and common technology for the resonance coupling power transfer. However, in 2007 it has experimentally demonstrated by a research group from Massachusets Institute of Technology (MIT) that WPT can be improved by using Magnetic Resonance Coupling Wireless Power Transfer (MRC WPT) in terms of the coupling distance and efficiency. Furthermore, by exploiting the unused, high-frequency mm-wave band which are ranging from 3~300 GHz frequency band, the next 5G generations of wireless networks will be able to support a higher number of devices with the increasing data rate, higher energy efficiency and also compatible with the previous technology. In this work, a square planar inductor with the dimension of 6.1 x 6.1 mm is designed, and the resonators have the same self-resonance frequency at 14 GHz. The coil resonators have been laid on Silicon and Oxide substrate to reduce the loss in the design. From the CST software simulation and the analytical model in MATLAB software, it has been shown that the MRC WPT design has improved the performance of IWPT design by 40% power transfer efficiency. MRC WPT design also has larger H-Field value which is 705.5 A/m, as compared to the IWPT design which has only 285.6 A/m when both Transmitter(Tx) and Reciever(RX) is at 0.3 mm coupling distance.
Proposed Model for Interference Estimation in Code Division Multiple AccessTELKOMNIKA JOURNAL
Cellular CDMA systems are usually affected by interference experienced by users in adjacent
cells that decrease the Quality of Services in wireless communication network. Hence, interference is the
limiting factor of capacity in CDMA cellular and it is one of the problems fighting against the high efficiency
of any mobile network. In this paper, a mathematical model to estimate the average number of users
contributing in inter-cell interference at the busy hours of CDMA network is proposed. As the power
exponent value has significant affect on interferer signal attenuation and hence other-cells interference,
measurements were carried through a drive test to determine the received power level at various distance
from CDMA base stations at Baghdad. The results obtained show that the power exponent was 2.71. This
value was applied in dual-slop path loss model to determine the expected interference factor, and the
number of users that can be hold at each cell. Simulations showed that users at a boundary cell generate
more interference than those close to the base station. Furthermore, it was denoted that greater number of
users caused to increase the interference factor, and greater power exponent value result in interference
factor reduction.
Mobility is one of the basic features that define an ad hoc network, an asset that leaves the field free for the
nodes to move. The most important aspect of this kind of network turns into a great disadvantage when it
comes to commercial applications, take as an example: the automotive networks that allow communication
between a groups of vehicles. The ad hoc on-demand distance vector (AODV) routing protocol, designed
for mobile ad hoc networks, has two main functions. First, it enables route establishment between a source
and a destination node by initiating a route discovery process. Second, it maintains the active routes, which
means finding alternative routes in a case of a link failure and deleting routes when they are no longer
desired. In a highly mobile network those are demanding tasks to be performed efficiently and accurately.
In this paper, we focused in the first point to enhance the local decision of each node in the network by the
quantification of the mobility of their neighbours. Quantification is made around RSSI algorithm a well
known distance estimation method.
AN ADVANCED QOS ANALYSIS AND EVALUATION METHOD FOR MOBILE INTERNET ACCESS ijwmn
The paper proposes a new method for the analysis and evaluation of the Quality of Service (QoS) in a
mobile Internet access scenario. In particular, the paper proposes a throughput evaluation method based
on PathChirp algorithm. The end-to-end bandwidth was estimated by means of the Self Loading of Periodic
Streams (SloPS) technique. The obtained measurements were then analyzed by estimating the degree of
correlation with other parameters that characterize the data transmission such as power, round trip time,
etc. Finally, in order to have greater spatial resolution performance guaranteed by an Internet service
provider, a 3D reconstruction method based on using drones is proposed and some preliminary results are
discussed.
Mobility and Propagation Models in Multi-hop Cognitive Radio Networksszhb
Cognitive radio networks allow unlicensed
(secondary) users to opportunistically utilize the idle
resource of a licensed network for communication
without affecting the quality of service being offered to
the primary or licensed users. This paper investigates
the effect of mobility on performance of multi-hop
cognitive radio network under various propagation
models. MPEG4 video; a bandwidth intensive traffic, is
tested over these network conditions for secondary
users and results are validated using NS2 simulations.
Performance metrics used for evaluation include
throughput, delay variations etc.
Design and Analysis of Broadband Elliptical Microstrip Patch Antenna for Wire...TELKOMNIKA JOURNAL
In this paper presents the design and manufacture of a new broadband elliptical patch antenna
with a microstrip feed line and optimum antenna parameters. The antenna dimension of
(30 × 21 × 1.6) 푚푚3 and fabricated on an FR-4 epoxy substrate having relative dielectric constant 휀푟=4.3,
loss tangent tan (δ)=0.002 and the feed line used has characteristic impedance of 50Ω.The designed
antenna has the capability of operating in the bandwidth (6.95-30.94) GHz and the gain (6.8) dBi. The
antenna performance was modified by inserting a slots in the ground plane to achieve impedance
bandwidth (when S11≤-10dB) and slots to patch to improve the gain. The modified antenna was designed
to be used for fifth generation (5G) mobile communication. The simulation results are obtained using CST
software.
A STRUCTURED DEEP NEURAL NETWORK FOR DATA-DRIVEN LOCALIZATION IN HIGH FREQUEN...IJCNCJournal
Next-generation wireless networks such as 5G and 802.11ad networks will use millimeter waves operating
at 28GHz, 38GHz, or higher frequencies to deliver unprecedentedly high data rates, e.g., 10 gigabits per
second. However, millimeter waves must be used directionally with narrow beams in order to overcome the
large attenuation due to their higher frequency. To achieve high data rates in a mobile setting,
communicating nodes need to align their beams dynamically, quickly, and in high resolution. We propose a
data-driven, deep neural network (DNN) approach to provide robust localization for beam alignment,
using a lower frequency spectrum (e.g., 2.4 GHz). The proposed DNN-based localization methods use the
angle of arrival derived from phase differences in the signal received at multiple antenna arrays to infer the
location of a mobile node. Our methods differ from others that use DNNs as a black box in that the
structure of our neural network model is tailored to address difficulties associated with the domain, such as
collinearity of the mobile node with antenna arrays, fading and multipath. We show that training our
models requires a small number of sample locations, such as 30 or fewer, making the proposed methods
practical. Our specific contributions are: (1) a structured DNN approach where the neural network
topology reflects the placement of antenna arrays, (2) a simulation platform for generating training and
evaluation data sets under multiple noise models, and (3) demonstration that our structured DNN approach
improves localization under noise by up to 25% over traditional off-the-shelf DNNs, and can achieve submeter
accuracy in a real-world experiment.
Propagation Path Loss Modeling and Outdoor Coverage Measurements Review in Mi...IJECEIAES
The global bandwidth inadequacy facing wireless carriers has motivated the exploration of the underutilized millimeter wave (mm-wave) frequency spectrum for future broadband cellular communication networks, and mmWave band is one of the promising candidates due to wide spectrum. This paper presents propagation path loss and outdoor coverage and link budget measurements for frequencies above 6 GHz (mm-wave bands) using directional horn antennas at the transmitter and omnidirectional antennas at the receiver. This work presents measurements showing the propagation time delay spread and path loss as a function of separation distance for different frequencies and antenna pointing angles for many types of real-world environments. The data presented here show that at 28 GHz, 38 GHz and 60 GHz, unobstructed Line of Site (LOS) channels obey free space propagation path loss while non-LOS (NLOS) channels have large multipath delay spreads and can utilize many different pointing angles to provide propagation links. At 60 GHz, there is more path loss and smaller delay spreads. Power delay profiles PDPs were measured at every individual pointing angle for each TX and RX location, and integrating each of the PDPs to obtain received power as a function of pointing angle. The result shows that the mean RMS delay spread varies between 7.2 ns and 74.4 ns for 60 GHz and 28 GHz respectively in NLOS scenario.
Enabling full-duplex in multiple access technique for 5G wireless networks ov...TELKOMNIKA JOURNAL
Nowadays, unmanned aerial vehicle (UAV) relays’assisted Internet of Things (IoT) systems provide facility in order to overcome the large scale fading between source and sink. The full-duplex scheme enables wireless network to provide higher spectrum efficient technology. This paper analyses performance of two users which are served by new emerging non-orthogonal multiple access (NOMA) technique. Exact outage probability of such two users are derived and checked via Monte-Carlo simulation. These analytical results provide guideline to design UAV in real application. This paper provides a comprehensive study to examine impact of interference, fixed power allocation factors to system performance.
ADAPTIVE RANDOM SPATIAL BASED CHANNEL ESTIMATION (ARSCE) FOR MILLIMETER WAVE ...IJCNCJournal
Millimeter-wave and mMIMO communications are the most essential success systems for next-generation wireless sensor networks to have enormous amounts of accessible throughput and spectrum. Through installing huge antenna arrays at the base station and performing coherent transceiver processing, mMIMO is a potential technology for enhancing the bandwidth efficiency of wireless sensor networks. The use of mmWave frequencies for mMIMO systems solves the problem of high path-loss through offering greater antenna gains. In this work, we provide a design with a random spatial sample structure that incorporates a totally random step before the analogue is received. It contains a totally random step before the analogue received signals are sent into the digital component of the HBF receiver. Adaptive random spatial based channel estimation (ARSCE) is proposed for channel session measurement collection, and an analogue combiner with valves has been used to estimate the signals at each receiving antenna. The proposed optimization problem formulation attempts to discover the orientations and gains of wideband channel routes. In addition, our proposed model has compared to various state-of-art techniques while considering error minimization.
Wideband Sensing for Cognitive Radio Systems in Heterogeneous Next Generation...CSCJournals
Mobile Next Generation Network (MNGN) is characterized as heterogeneous network where variety of access technologies are meant to coexist. Decisions on choosing an air interface that meets a particular need at a particular time will be shifted from the network’s side to (a more intelligent) user’s side. On top of that network operators and regularities have come to the realization that assigned spectrum bands are not utilized as they should be. Cognitive radio stands out as a candidate technology to address many emerging issues in MNGN such as capacity, quality of service and spectral efficiency. As a transmission strategy, cognitive radio systems depend greatly on sensing the radio environment. In this paper, we present a novel approach for interference characterization in cognitive radio networks based on wideband chirp signal. The results presented show that improved sensing accuracy is maintained at tolerable system complexity.
Efficient energy, cost reduction, and QoS based routing protocol for wireless...IJECEIAES
Recent developments and widespread in wireless sensor network have led to many routing protocols, many of these protocols consider the efficiency of energy as the ultimate factor to maximize the WSN lifetime. The quality of Service (QoS) requirements for different applications of wireless sensor networks has posed additional challenges. Imaging and data transmission needs both QoS aware routing and energy to ensure the efficient use of sensors. In this paper, we propose an Efficient, Energy-Aware, Least Cost, (ECQSR) quality of service routing protocol for sensor networks which can run efficiently with best-effort traffic processing. The protocol aims to maximize the lifetime of the network out of balancing energy consumption across multiple nodes, by using the concept of service differentiation, finding lower cost by finding the shortest path using nearest neighbor algorithm (NN), also put certain constraints on the delay of the path for real-time data from where link cost that captures energy nodes reserve, energy of the transmission, error rate and other parameters. The results show that the proposed protocol improves the network lifetime and low power consumption.
A Novel Routing Strategy Towards Achieving Ultra-Low End-to-End Latency in 6G...IJCNCJournal
Compared to 5G, 6G networks will demand even more ambitious reduction in endto-end latency for packet communication. Recent attempts at breaking the barrier of end-to-end millisecond latencies have focused on re-engineering networks using a hybrid approach consisting of an optical-fiber based backbone network architecture coupled with high-speed wireless networks to connect end-devices to the backbone network. In our approach, a wide area network (WAN) is considered with a high-speed optical fiber grid network as its backbone. After messages from a source node enter the backbone network through a local wireless network, these are delivered very fast to an access point in the backbone network closest to the destination node, followed by its transfer to the local wireless network for delivery to the destination node. We propose a novel routing strategy which is based on distributing the messages in the network in such a way that the average queuing delay of the messages through the backbone network is minimized, and also the route discovery time at each router in the backbone network is drastically reduced. Also, multiple messages destined towards a particular destination router in the backbone network are packed together to form a mailbag, allowing further reductions in processing overheads at intermediate routers and pipelining of mailbag formation and route discovery operations in each router. The performance of the proposed approach green based on these ideas has been theoretically analyzed and then simulated using the ns-3 simulator. Our results show that the average end-to-end latency is less than 380 µs (with only 46-79 µs within the backbone network under varying traffic conditions) for a 1 KB packet size, when using a 500 Gbps optical fiber based backbone network laid over a 15 Km × 15 Km area, a 50 Mbps uplink channel from the source to the backbone network, and a 1 Gbps downlink channel from the backbone network to the destination. The significant reduction in end-to-end latency as compared to existing routing solutions clearly demonstrates the potential of our proposed routing strategy for meeting the ultra-low latency requirements of current 5G and future 6G networks, particularly for mobile edge computing (MEC) application scenarios.
ADAPTIVE SENSOR SENSING RANGE TO MAXIMISE LIFETIME OF WIRELESS SENSOR NETWORK IJCNCJournal
Wireless Sensor Network (WSN) is commonly used to collect information from a remote area and one of the most important challenges associated with WSN is to monitor all targets in a given area while maximizing network lifetime. In wireless communication, energy consumption is proportional to the breadth of sensing range and path loss exponent. Hence, the energy consumption of communication can be minimized by varying the sensing range and decreasing the number of messages being sent. Sensing energy can be optimized by reducing the repeated coverage target. In this paper, an Adaptive Sensor Sensing Range (ASSR) technique is proposed to maximize the WSN Lifetime. This work considers a sensor network with an adaptive sensing range that are randomly deployed in the monitoring area. The sensor is adaptive in nature and can be modified in order to save power while achieving maximum time of monitoring to increase the lifetime of WSN network. The objective of ASSR is to find the best sensing range for each sensor to cover all targets in the network, which yields maximize the time of monitoring of all targets and eliminating double sensing for the same target. Experiments were conducted using an NS3 simulator to verify our proposed technique. Results show that ASSR is capable to improve the network lifetime by 20% as compared to other recent techniques in the case of a small network while achieving an 8% improvement for the case of a large networks.
Performance Enhancement in SU and MU MIMO-OFDM Technique for Wireless Communi...IJECEIAES
The consistent demand for higher data rates and need to send giant volumes of data while not compromising the quality of communication has led the development of a new generations of wireless systems. But range and data rate limitations are there in wireless devices. In an attempt to beat these limitations, Multi Input Multi Output (MIMO) systems will be used which also increase diversity and improve the bit error rate (BER) performance of wireless systems. They additionally increase the channel capacity, increase the transmitted data rate through spatial multiplexing, and/or reduce interference from other users. MIMO systems therefore create a promising communication system because of their high transmission rates without additional bandwidth or transmit power and robustness against multipath fading. This paper provides the overview of Multiuser MIMO system. A detailed review on how to increase performance of system and reduce the bit error rate (BER) in different fading environment e.g. Rayleigh fading, Rician fading, Nakagami fading, composite fading.
Magnetic resonance coupling for 5G WPT applicationsjournalBEEI
Inductive Wireless Power Transfer (IWPT) is the most popular and common technology for the resonance coupling power transfer. However, in 2007 it has experimentally demonstrated by a research group from Massachusets Institute of Technology (MIT) that WPT can be improved by using Magnetic Resonance Coupling Wireless Power Transfer (MRC WPT) in terms of the coupling distance and efficiency. Furthermore, by exploiting the unused, high-frequency mm-wave band which are ranging from 3~300 GHz frequency band, the next 5G generations of wireless networks will be able to support a higher number of devices with the increasing data rate, higher energy efficiency and also compatible with the previous technology. In this work, a square planar inductor with the dimension of 6.1 x 6.1 mm is designed, and the resonators have the same self-resonance frequency at 14 GHz. The coil resonators have been laid on Silicon and Oxide substrate to reduce the loss in the design. From the CST software simulation and the analytical model in MATLAB software, it has been shown that the MRC WPT design has improved the performance of IWPT design by 40% power transfer efficiency. MRC WPT design also has larger H-Field value which is 705.5 A/m, as compared to the IWPT design which has only 285.6 A/m when both Transmitter(Tx) and Reciever(RX) is at 0.3 mm coupling distance.
Proposed Model for Interference Estimation in Code Division Multiple AccessTELKOMNIKA JOURNAL
Cellular CDMA systems are usually affected by interference experienced by users in adjacent
cells that decrease the Quality of Services in wireless communication network. Hence, interference is the
limiting factor of capacity in CDMA cellular and it is one of the problems fighting against the high efficiency
of any mobile network. In this paper, a mathematical model to estimate the average number of users
contributing in inter-cell interference at the busy hours of CDMA network is proposed. As the power
exponent value has significant affect on interferer signal attenuation and hence other-cells interference,
measurements were carried through a drive test to determine the received power level at various distance
from CDMA base stations at Baghdad. The results obtained show that the power exponent was 2.71. This
value was applied in dual-slop path loss model to determine the expected interference factor, and the
number of users that can be hold at each cell. Simulations showed that users at a boundary cell generate
more interference than those close to the base station. Furthermore, it was denoted that greater number of
users caused to increase the interference factor, and greater power exponent value result in interference
factor reduction.
Mobility is one of the basic features that define an ad hoc network, an asset that leaves the field free for the
nodes to move. The most important aspect of this kind of network turns into a great disadvantage when it
comes to commercial applications, take as an example: the automotive networks that allow communication
between a groups of vehicles. The ad hoc on-demand distance vector (AODV) routing protocol, designed
for mobile ad hoc networks, has two main functions. First, it enables route establishment between a source
and a destination node by initiating a route discovery process. Second, it maintains the active routes, which
means finding alternative routes in a case of a link failure and deleting routes when they are no longer
desired. In a highly mobile network those are demanding tasks to be performed efficiently and accurately.
In this paper, we focused in the first point to enhance the local decision of each node in the network by the
quantification of the mobility of their neighbours. Quantification is made around RSSI algorithm a well
known distance estimation method.
AN ADVANCED QOS ANALYSIS AND EVALUATION METHOD FOR MOBILE INTERNET ACCESS ijwmn
The paper proposes a new method for the analysis and evaluation of the Quality of Service (QoS) in a
mobile Internet access scenario. In particular, the paper proposes a throughput evaluation method based
on PathChirp algorithm. The end-to-end bandwidth was estimated by means of the Self Loading of Periodic
Streams (SloPS) technique. The obtained measurements were then analyzed by estimating the degree of
correlation with other parameters that characterize the data transmission such as power, round trip time,
etc. Finally, in order to have greater spatial resolution performance guaranteed by an Internet service
provider, a 3D reconstruction method based on using drones is proposed and some preliminary results are
discussed.
Effective Road Model for Congestion Control in VANETSijwmn
Congestion on the roads is a key problem to deal with, which wastes valuable time.. Due to high mobility
rate and relative speed link failure occur very often. VANET is used to tackle the problem of congestion,
and make decisions well in advance to avoid traffic congestion. In this paper we proposed a solution to
detect and control the traffic congestion by using of both (V2V) and (V2I), as a result the drivers become
aware of the location of congestion as well as way to avoid getting stuck in congestion. The congestion is
detected by analyzing the data obtained by vehicular communication and road side units to avoid the
traffic. Our proposition system is competent of detecting and controlling traffic congestion in real-time.
V2V and V2I communication network is used to receive and send the messages. We simulate the result by
using Congestion Detection and Control Algorithm (CDCA), and show that this is one effective way to
control congestion. The Proposed methodology ensures reliable and timely delivery of messages to know
about congestion and avoid it.
Connectivity aware and adaptive multipath routing algorithm for mobile adhoc ...ijwmn
We propose in this paper a connectivity-aware routing algorithm and a set of related theorems. This algorithm allows nodes in Mobile Adhoc and Sensor Networks (MASNets) to provide the highest connectivity life time to a specific destination since the issuance of data becomes a necessity for MASNets. In the proposed Solution, nodes in MASNets are able to specify the disjointness degree of the available paths allowing the discovery of the optimal set of backup routes and consequently enhance the survivability of the connectivity. These nodes perform an on-demand discovery and a generation of a set of routes, by specifying a disjointness threshold, representing the maximal number of nodes shared between any two paths in the set of k established paths. The proposed multipath routing algorithm, is adaptive, secure, and uses labels to carry the disjointness-threshold between nodes during the route discovery. A set of security mechanisms, based on the Watchdog and the digital signature concepts, is used to protect the route discovery process.
SENSOR SELECTION SCHEME IN TEMPERATURE WIRELESS SENSOR NETWORKijwmn
In this paper, we propose a novel energy efficient environment monitoring scheme for wireless sensor
networks, based on data mining formulation. The proposed adapting routing scheme for sensors for
achieving energy efficiency from temperature wireless sensor network data set. The experimental
validation of the proposed approach using publicly available Intel Berkeley lab Wireless Sensor Network
dataset shows that it is possible to achieve energy efficient environment monitoring for wireless sensor
networks, with a trade-off between accuracy and life time extension factor of sensors, using the proposed
approach.
A fuzzy congestion controller to detect and balance congestion in wsnijwmn
A Wireless Sensor Network (WSN) is collection of wireless sensors with limited memory, processing and energy supply. Based on application, sensors distribute in a wide geographically area in order to collect information and transmit the collected data packets toward a base station also called Sink. Due to the relatively high node density and source-to-sink communication pattern, congestion is a critical issue in WSN. Congestion not only causes packet loss, but also leads to excessive energy consumption as well as delay. To address this problem, in this paper we propose a new fuzzy logic based mechanism to detect and control congestion in each grid in WSN. In the proposed approach, sink select one node in each grid as Monitor Node. In addition, sink defines congestion candidate grids. Each Monitor Node in congestion candidate grids continually monitors the network and fetches the fuzzy controller inputs in order to determine level of congestion in each grid. Based on the congestion level, packets forward through the grid or relay nodes. Simulation results show that our approach has higher packet delivery ratio and lower packet loss than existing approaches.
A SEMI BLIND CHANNEL ESTIMATION METHOD BASED ON HYBRID NEURAL NETWORKS FOR UP...ijwmn
The paper describes how to improve channel estimation in Single Carrier Frequency Division Multiple
Access (SC-FDMA) system, using a Hybrid Artificial Neural Networks (HANN). The 3rd Generation
Partnership Project (3GPP) standards for uplink Long Term Evolution Advanced (LTE-A) uses pilot based
channel estimation technique. This kind of channel estimation method suffers from a considerable loss
ofbitrate due to pilot insertion; all data frame sent contains reference signal. The HANN converts data
aided channel estimator to semi blind channel estimator. To increase convergence speed, HANN uses some
channel propagation Fuzzy Rules to initialize Neural Network parameters before learning instead of a
random initialization, so its learning phase ismore rapidly compared to classic ANN.HANN allows more
bandwidth efficient and less complexity. Simulation results show that HANN has better computational
efficiency than the Minimum Mean Square Error (MMSE) estimator and has faster convergence than
classic Neural Networks estimators.
System level simulation for two tier macro femto cellular networksijwmn
LTE is an emerging wireless communication technology to provide high- speed data service for the mobile
phones and data terminals. To improve indoor coverage and capacity Femtocells are included in 3GPP
since Release 8. There is no common simulation platform is available for performance justification of LTEFemtocells.
LTE-Sim is an object-oriented open source simulator which incorporates a complete protocol
stack can be used for simulating two-tier macro-femto scenarios. To the best of our knowledge no paper
provides the guideline to perform system level simulation of Femtocell networks. Here, in this paper
Femtocells performance is evaluated in multi-Macrocells and multi-Femtocells environment with
interference from Microcells and Macrocell users along with the scripting.
Energy balanced on demand clustering algorithm based on leach-cijwmn
As the use of Wireless Sensor Networks (WSNs) has grown enormously, the need for energy-efficient management has also risen. With advances in ubiquitous computing environment, WSNs have been broadly studied and many energy-efficient routing protocols had been proposed. LEACH (Low Energy Adaptive Clustering Hierarchy) is a popular cluster-based protocol, which provides distributed adaptive clustering and periodic cluster head (CH) selection rotation. As extension to LEACH, LEACH-C (LEACH Centralized) was proposed, in which the energy is utilized to select CH. However, both can’t guarantee cluster head distribution, in addition to considerable periodic clustering overhead. Furthermore, network topology change is a critical characteristic that has influence on communication path and load distribution among nodes. To resolve such problems, Energy-Balance on Demand Clustering Algorithm Based on LEACH-C is proposed. The algorithm adopts centralized cluster formation and distributed CH selection methods. Minimum energy clustering is used to divide the network into clusters, while energy and total communication distance are considered as secondary criteria to select optimal CH. From simulation results the proposed algorithm outperforms LEACH-C in life time, stability period and performance efficiency.
DEVICE-TO-DEVICE (D2D) COMMUNICATION UNDER LTE-ADVANCED NETWORKSijwmn
Device-to-Device (D2D) communication is a new technology that offer many advantages for the LTEadvanced
network such us wireless peer-to-peer services and higher spectral efficiency. It is also
considered as one of promising techniques for the 5G wireless communications system and used in so
many different fields such as network traffic offloading, public safety, social services and applications such
as gaming and military applications . The goal of this paper is to present advances on the current 3GPP
LTE-advanced system related to Device-to-Device (D2D). In this paper, we provide an overview of the
D2D types based on the communication spectrum of D2D transmission, namely Inband D2D
communication and Outband D2D communication. Then we present the advantages and disadvantages of
each D2D mode. Moreover, architecture and protocol enhancements for D2D communications under
LTE-A network are described.
ENERGY EFFICIENT GRID AND TREE BASED ROUTING PROTOCOLijwmn
In Wireless Sensor Network, a large number of sensor nodes are deployed and they mainly consume energy
in transmitting data over long distances. Sensor nodes are battery powered and their energy is restricted.
Since the location of the sink is remote, considerable energy would be consumed if each node directly
transmits data to the base station. Aggregating data at the intermediate nodes and transmitting using multihops
aids in reducing energy consumption to a great extent. This paper proposes a hybrid protocol
“Energy efficient Grid and Tree based routing protocol” (EGT) in which the sensing area is divided into
grids. The nodes in the grid relay data to the cell leader which aggregates the data and transmits to the
sink using the constructed hop tree. Simulation results show that EGT performs better than LEACH.
L shaped slot loaded semicircular patch antenna for wideband operation ijwmn
In this paper, a dual frequency resonance antenna is analysed by introducing L-shaped slot in a semi
circular patch, different parametric studies have allows and the results in terms of return loss and
radiation pattern are given. The results show that dual wide bands are achieved and a better impedance
matching for the upper and lower resonance are obtained. Also, it is observed that various antenna
parameters are obtained as a function of frequency for different value of slot length and width; it is easy to
adjust the upper and the lower band by varying these different antenna parameters. The coaxial feed is
used to excite the patch antenna. Theoretical results using Matlab are compared with the simulated results
obtained from Ansoft HFSS software and shown to be in good agreement.
BEHAVIOUR OF ROUTING PROTOCOLS IN MOBILE AD HOC NETWORKS INVESTIGATED FOR EME...ijwmn
Mobile Ad hoc Networks are open, shared, dynamic and self-organized networks. These distinct nature
lead to efficient use in emergency and recue scenarios where the sharing of information is necessary. In
order to share information within the network, a proper routing protocol is required to establish routes
between nodes. This article discusses which of the routing protocols such as reactive or proactive has
better performance in such scenario. In order to implement the test bed, we choose a real area in
Uttarakhand state, India where the disaster occurred recently hence so many civilizations had vanished
due to lack of communication and failure in recovery. Our aim is to choose an optimum routing protocol
that is correct and used for efficient route establishment between nodes so that message could be delivered
on time without loss and it will be implemented and used in future based on the model that we propose.
Steganography is a technology used since years for the communication of messages secretly. These secret messages are put inside honest carriers. Carriers can be digital images, audio files, video files and so on. The limitation in sending concealed longer messages has been overcoming by the inclusion of video files as carriers. Popular internet services such as Skype, BitTorrent, Google Suggest, and
WLANs are targets of information hiding techniques. Nowadays, plotters are not only using the carriers but also the protocols for communication that regulate the path of the carrier through the Internet. This technique is named Network Steganography.
B ENCHMARKING OF C ELL T HROUGHPUT U SING P ROPORTIONAL F AIR S CHEDULE...ijwmn
The proportional fair (PF) scheduling algorithm com
promises between cell throughput and fairness. Many
research findings have been published by various re
searchers about PF algorithm based on mathematical
model and simulations. In this paper we have taken
the practical route to analyse the algorithm based
on
three types of subscription. In this benchmarking s
tudy, the user subscriptions are differentiated as
Gold,
Silver and Bronze schemes and they are provisioned
with certain throughputs. Apart from subscriptions
plans, the channel condition also plays a major rol
e in determining the throughput. So in order to ens
ure
fairness among different subscriptions even in the
bad channel conditions and to deliver the provision
ed
throughputs certain priorities are attached with th
e subscriptions. As per the subscription plans Gold
subscribers are assigned with 50% of the speed offe
red by the network as maximum based on CAT3 speed
(100 Mbps in DL and 50 Mbps in UL), Silver is assig
ned with 25% of the max speed and Bronze is
assigned with 12% of the max speed. The priorities
assigned to subscribers determines the fairness in
the
unfavourable channel conditions - Bronze (high), Si
lver and Gold (medium). In this paper, an
benchmarking tests have been performed with all of
three types of subscribers for nearly two hours in
the
live single cell network without any heterogeneous
cells influencing it. Furthermore, the results are
compared with the simulation results.
In ad hoc networks, routing plays a pertinent role. Deploying the appropriate routing protocol is very important in order to achieve best routing performance and reliability. Equally important is the mobility model that is used in the routing protocol. Various mobility models are available and each can have different impact on the performance of the routing protocol. In this paper, we focus on this issue by examining how the routing protocol, Optimized Link State Routing protocol, behaves as the mobility model is varied. For this, three random mobility models, viz., random waypoint, random walk and random direction are considered. The performance metrics used for assessment of Optimized Link State Routing protocol are throughput, end-to-end delay and packet delivery ratio.
Interference management in lte downlink networksijwmn
Two major challenges for evolving LTE (Long Term Evolution) networks are to achieve enhanced system capacity and cell coverage compared with WCDMA (Wideband Code Division Multiple Access) system. Effective utilization of radio resources as well as dense spectrum reuse are at the core to attain these targets. However, dense frequency reuse may increase inter-cell interference, which in turn severely limits the capacity of users in the system. Inter-cell interference can restrict overall system performance in terms of throughput and spectral efficiency, especially for the users located at the cell edge area. Hence, careful management of inter-cell interferences becomes crucial to improve LTE system performance. In this paper, interference mitigation schemes for LTE downlink networks are investigated.
Although unmanned aerial vehicles (UAVs) were mostly studied and used for military purposes before, they
have become very popular recently for both civil uses, such as law enforcement and crop survey, and for
potential commercial uses such as grocery delivery and Internet extension. Researchers investigating new
networking protocols for UAV networks usually need the help of simulations to test their protocol designs,
particularly when networks of large scales are desired in their tests. One choice that researchers need to
make in the simulation of UAV networks is the radio propagation model for the air links. In this paper we
compare the three radio propagation models that are available in the ns2 network simulation package and
investigate if the choice of one particular model would have a significant impact on the simulation results
for UAV networks.
PERFORMANCE OF TCP CONGESTION CONTROL IN UAV NETWORKS OF VARIOUS RADIO PROPAG...IJCNCJournal
Unmanned aerial vehicles (UAVs) have recently become popular for both recreational and commercial use
and UAV networks have thus started to attract the attention of researchers in area of the computer
communication and networking. One important topic in UAV networks is congestion control because
congestion causes packet losses and delays which result in the waste of all types of network resources such
as bandwidth and power. Although there are studies on the performance of TCP congestion control in
wireless networks, they focus on terrestrial networks of two dimensions in general. In this paper we study
the performance of TCP congestion control in three dimensional UAV networks. In particular, we
investigate how TCP congestion control performs in such type of network using various radio propagation
models. Our data on the average flow throughput, packet delay, and packet loss rate in UAV networks
show that TCP congestion control improves the network performance of UAV networks in general, but it
faces challenges when the link losses become severe. Our study thus shows that investigation on new
congestion control schemes is stilled needed for the emerging UAV networks.
Experimental simulation and real world study on wi fi ad-hoc mode for differe...Nazmul Hossain Rakib
The Ad-Hoc mode for wireless communication is not used frequently. But the demand for Wi-Fi communication is continuously increasing as use of Smart-phones and Laptops has enormously popular recent years. Through Ad-Hoc mode users can communicate point to point with mobility feature without using any central BSS. Wireless Ad-Hoc mode uses electromagnetic wave and so this technology has losses and limitations caused by free space propagation media as well as attenuation for interferences.
Improvement of crankshaft MAC protocol for wireless sensor networks: a simula...IJECEIAES
Due to the dramatic growth in the use of Wireless Sensor Network (WSN) applications ranging from environment and habitat monitoring to tracking and surveillance, network research in WSN protocols has been very active in the last decade. With battery-powered sensors operating in unattended environments, energy conservation becomes the key technique for improving WSN lifetimes. WSN Medium Access Control (MAC) protocols address energy awareness and reduced duty cycles. The focus of this study is to investigate, through simulation, the effect of variations in various factors that influence the performance results of WSNs. Using MiXiM framework with OMNeT++ simulator, this simulation study proposes modifications in Crankshaft MAC protocol in order to improve its performance. The impact of duration and number of slots, degree of connectivity among the nodes, mobility speed and mobility update interval and also, the impact of sending data packets without preambles are investigated. Based on the simulation results, an improved version of the Crankshaft protocol for WSN is suggested and a comparative study of the performances of the original and improved protocol is presented. The results clearly indicate the superiority of the improved protocol over its original version.
Performance and interference analysis of 802.11 g wireless networkijwmn
This paper mainly presents Access Point s’ (APs’) p
erformance and co-channel, adjacent channel
interference according to 802.11g standard. Firstly
, our study illustrates the performance of one AP,
including its coverage performance, load-carrying p
roperties and fairness. Next we propose the details
about co-channel, adjacent channel interference whi
ch should be paid attention to in deploying network
services. Then, performance analyses are evaluated
by simulation and real test for a dense wireless
network. Our contribution is that the co-channel, a
djacent channel interference analysis, the simulati
on
and test results can be the basis offered to networ
k operators
SHADOWING EFFECTS ON ROUTING PROTOCOL OF MULTIHOP AD HOC NETWORKSijasuc
Two-ray ground reflection model has been widely used as the propagation model to investigate the
performance of an ad hoc network. But two-ray model is too simple to represent a real world network. A
more realistic model namely shadowing propagation model has been used in this investigation. Under
shadowing propagation model, a mobile node may receive a packet at a signal level that is below a
required threshold level. This low signal level affects the routing protocol as well as the medium access
control protocol of a network. An analytical model has been presented in this paper to investigate the
shadowing effects on the network performance. The analytical model has been verified via simulation
results. Simulation results show that the performance of a network becomes very poor if shadowing
propagation model is used in compare to the simple two-ray model. Two solutions have also been proposed
in this paper to overcome the effects of shadowing. One solution is a physical layer solution and the other
one is a Medium Access Control (MAC) layer solution. Simulation results show that these two solutions
reduce the shadowing effect and improve network performance.
SHADOWING EFFECTS ON ROUTING PROTOCOL OF MULTIHOP AD HOC NETWORKSijasuc
Two-ray ground reflection model has been widely used as the propagation model to investigate the
performance of an ad hoc network. But two-ray model is too simple to represent a real world network. A
more realistic model namely shadowing propagation model has been used in this investigation. Under
shadowing propagation model, a mobile node may receive a packet at a signal level that is below a
required threshold level. This low signal level affects the routing protocol as well as the medium access
control protocol of a network. An analytical model has been presented in this paper to investigate the
shadowing effects on the network performance. The analytical model has been verified via simulation
results. Simulation results show that the performance of a network becomes very poor if shadowing
propagation model is used in compare to the simple two-ray model. Two solutions have also been proposed
in this paper to overcome the effects of shadowing. One solution is a physical layer solution and the other
one is a Medium Access Control (MAC) layer solution. Simulation results show that these two solutions
reduce the shadowing effect and improve network performance.
SHADOWING EFFECTS ON ROUTING PROTOCOL OF MULTIHOP AD HOC NETWORKSijasuc
Two-ray ground reflection model has been widely used as the propagation model to investigate the
performance of an ad hoc network. But two-ray model is too simple to represent a real world network. A
more realistic model namely shadowing propagation model has been used in this investigation. Under
shadowing propagation model, a mobile node may receive a packet at a signal level that is below a
required threshold level. This low signal level affects the routing protocol as well as the medium access
control protocol of a network. An analytical model has been presented in this paper to investigate the
shadowing effects on the network performance. The analytical model has been verified via simulation
results. Simulation results show that the performance of a network becomes very poor if shadowing
propagation model is used in compare to the simple two-ray model. Two solutions have also been proposed
in this paper to overcome the effects of shadowing. One solution is a physical layer solution and the other
one is a Medium Access Control (MAC) layer solution. Simulation results show that these two solutions
reduce the shadowing effect and improve network performance.
LABORATORY ANALYSIS ON THE PERFORMANCE OF 5G NSA COMMUNICATION IN A SUBURBAN ...ijwmn
The propagation of information by electromagnetic waves suffers different types of interference, according
to the characteristics of the environment. The 5G system relies on adaptive modulation and coding
techniques to better suit the channel and maximize effective data exchange between the user equipment and
the network. Practical studies on the behaviour of the system under different environmental conditions,
subject to attenuation processes such as fading, are important to understand and improve the 5G
efficiency. This work has analysed the effect of the MCS (Modulation and Coding Scheme) variation on
throughput for channel degraded by the multipath fading effect in a mobile communication. The analysis
was carried out showing that the decision algorithms in terms of MCS switching to maintain adequate data
rates according to the requirement (QoS) is an important factor. Considering both 64 QAM and 256 QAM,
the throughput degradation effect was more evident in higher-order modulations due to the higher
probability of bit error in the symbol constellation. This study can be a key for understanding and
developing robust MCS switcher for 5G and beyond communications.
LABORATORY ANALYSIS ON THE PERFORMANCE OF 5G NSA COMMUNICATION IN A SUBURBAN ...ijwmn
The propagation of information by electromagnetic waves suffers different types of interference, according
to the characteristics of the environment. The 5G system relies on adaptive modulation and coding
techniques to better suit the channel and maximize effective data exchange between the user equipment and
the network. Practical studies on the behaviour of the system under different environmental conditions,
subject to attenuation processes such as fading, are important to understand and improve the 5G
efficiency. This work has analysed the effect of the MCS (Modulation and Coding Scheme) variation on
throughput for channel degraded by the multipath fading effect in a mobile communication. The analysis
was carried out showing that the decision algorithms in terms of MCS switching to maintain adequate data
rates according to the requirement (QoS) is an important factor. Considering both 64 QAM and 256 QAM,
the throughput degradation effect was more evident in higher-order modulations due to the higher
probability of bit error in the symbol constellation. This study can be a key for understanding and
developing robust MCS switcher for 5G and beyond communications.
Performance of modeling wireless networks in realistic environmentCSCJournals
A wireless network is realized by mobile devices which communicate over radio channels. Since, experiments of real life problem with real devices are very difficult, simulation is used very often. Among many other important properties that have to be defined for simulative experiments, the mobility model and the radio propagation model have to be selected carefully. Both have strong impact on the performance of mobile wireless networks, e.g., the performance of routing protocols varies with these models. There are many mobility and radio propagation models proposed in literature. Each of them was developed with different objectives and is not suited for every physical scenario. The radio propagation models used in common wireless network simulators, in general researcher consider simple radio propagation models and neglect obstacles in the propagation environment. In this paper, we study the performance of wireless networks simulation by consider different Radio propagation models with considering obstacles in the propagation environment. In this paper we analyzed the performance of wireless networks by OPNET Modeler .In this paper we quantify the parameters such as throughput, packet received attenuation.
THE PERFORMANCE OF CONVOLUTIONAL CODING BASED COOPERATIVE COMMUNICATION: RELAYIJCNCJournal
Wireless communication faces adversities due to noise, fading, and path loss. Multiple-Input MultipleOutput (MIMO) systems are used to overcome individual fading effect by employing transmit diversity. Duo to user single-antenna, Cooperation between at least two users is able to provide spatial diversity. This paper presents the evaluation of the performances of the Amplify and Forward (AF) cooperative system for different relay positions using several network topologies over Rayleigh and Rician fading channel. Furthermore, we present the performances of AF cooperative system with various power allocation. The results show that cooperative communication with convolutional coding shows an outperformance compared to the non-convolutional, which is a promising solution for high data-rate networks such as (WSN), Ad hoc, (IoT), and even mobile networks. When topologies are compared, the simulation shows that, linear topology offers the best BER performance, in contrast when the relay acts as source and the source take the relay place, the analysis result shows that, equilateral triangle topology has the best BER performance and stability, and the system performance with inter-user Rician fading channel is better than the performance of the system with inter-user Rayleigh fading channel.
Wireless Transmission System for the Improved Reliability in the Flying Ad-ho...IJERA Editor
Unmanned aerial vehicle (UAV) has unlimited availability not only in war but in various fields such as reconnaissance, observation, exploration. The wireless communication system between UAVs is very important and is known as flying ad-hoc network (FANET). The reason is that the FANET for UAV transfers data such as the information on mission accomplishment, collision prevention, etc. Therefore, the FANETs require the robust and spectral efficient communication scheme in the fading channel. Due to the high-mobility of the UAVs, these channels are very dynamic and time varying channel. In a dynamic channel environment, the adaptive modulation and coding (AMC) scheme is necessary to provide a reliable communication. This paper provides the improved wireless communication scheme applied with the AMC scheme. The proposed scheme uses the modulation and coding according to the channel state information (CSI) in the FANETs. The receiver obtains the CSI by using the channel estimation and transmits the feedback information to the transmitter. And then, the transmitter confirms the channel conditions via the CSI and adaptively uses the modulation scheme and code rate according to the channel conditions. Because the proposed scheme provides the reliable wireless communication, it does not require unnecessary re-transmission
Capacity Improvement of Cellular System Using Fractional Frequency Reuse (FFR)IJEEE
Today wireless communication is mostly used rather than wired communication, due to remote location reach ability, less fault occurrence, less time to commissioning and low cost etc. But wireless network has less frequency spectrum to cover the whole world. To improve the capacity of cellular system in a limited spectrum without major technological changes, frequency is reused in cells. But it offers interferences mostly for cell edge users. To solve the problem of spectral congestion and user capacity, fractional frequency reuse is used. This paper gives idea about different frequency reuse factors, fractional frequency reuse and super cell with sectoring to improve the capacity of cellular system.
802.11g Signal Strength Evaluation in an Industrial Environment (Elsevier Int...Dalton Valadares
This paper was submitted to the Elsevier Internet of Things Journal (ISSN: 2542-6605) and is an extension of the AINA2019 paper: "Towards 802.11g Signal Strength Estimation in an Industrial Environment: A Practical Study".
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
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The shadowing propagation model
1. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
DOI : 10.5121/ijwmn.2015.7408 103
THE SHADOWING PROPAGATION MODEL
IN UNMANNED AERIAL VEHICLE
NETWORKS
Jun Peng
Electrical Engineering Department
University of Texas – Rio Grande Valley
Edinburg, Texas, USA
ABSTRACT
Unmanned aerial vehicles (UAVs) have become very popular recently for both civil uses and potential
commercial uses, such as law enforcement, crop survey, grocery delivery, and photographing, although
they were mainly used for military purposes before. Researchers need the help of simulations when they
design and test new protocols for UAV networks because simulations can be done for a network of a size
that a test bed can hardly approach. In the simulation of an UAV network it is important to choose a radio
propagation model for the links in the network. We study the shadowing radio propagation model in this
paper and compare it with the free space model, both of which are available in the ns2 network simulation
package. We also show how the choice of the parameters of the shadowing model would impact on the
network performance of a UAV network.
KEYWORDS
The shadowing model, propagation models, unmanned aerial vehicles (UAV), network Simulation
1. INTRODUCTION
Unmanned aerial vehicles had been mainly used in military applications before, but they became
popular in recent years in both civilian and commercial applications, as hardware and software
became more advanced and cheaper. For example, people started to use UAVs to film subjects
from perspectives that they could hardly imagine or reach before due to the high cost of having an
access to a plane or helicopter. Other advantages of using UAVs in such an application include
safety, efficiency, and environmental friendliness. UAVs have also been used for law
enforcement, crowd management, surveillance, search and rescue, and scientific research [1].
It will become inevitable that UAVs will need to communicate with each other for purposes of
coordination and collaborations in the future, as they become more and more popular in civilian
and commercial applications. One example is that UAVs will likely need some type of
coordination in the future to avoid collisions among themselves. Another example is that
applications requiring a large amount of UAVs working together dynamically, such as doing a
constant surveillance on a large geographical area, will also need the UAVs to communicate with
each other effectively.
2. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
104
Researchers have been investigating topics at all layers of UAV networks to enable UAVs for
networking. Asadpour et al. [2] studied the performance of IEEE 802.11n interfaces in UAV
networks and they found that 802.11n performed poorly in highly mobile scenarios. Cai et cal. [3]
proposed a medium access control (MAC) protocol for UAV ad-hoc networks with full-duplex
radios. They proposed a token based technique to update information in the network for
efficiently handling the high mobility of UAVs. Ollero et al. [4] presented a platform that enables
autonomous aerial vehicles to cooperate with ground wireless sensor-actuator networks. Alshbatat
et al. [5] used the approach of cross layer design to deal with the high dynamics in UAV
networks. Alshbatat et al. [6] also proposed an adaptive medium access control protocol for UAV
networks using directional antennas. Gu et al. [7] proposed a routing scheme for multi-layer ad
hoc networks that use UAVs in their backbones. Gu et al. [8] also presented a multiple access
protocol for such type of network.
When UAV networks of large scales are needed in testing communication and networking
protocols, simulations are usually the only practical way that would be available to most
researchers. One important choice in simulating an UAV network is the radio propagation model
used in the network. There are several radio propagation models that are available in the ns-2
network simulation package [9]. Although there are studies on some of these radio propagation
models for vehicular networks [2], they in general focus on terrestrial networks. In this paper we
investigate the shadowing model in UAV networks and show how the choice of its parameters
may have an impact on the performance of the simulated network. We also compare the
shadowing model with the free space propagation model in the paper.
The rest of the paper is organized as follows. We introduce the the shadowing radio propagation
model and the free space loss model in Section 2. We present in Section 3 numerical results on
these two models using simulations. We finally make our conclusions in Section 4.
2. THE SHADOWING RADIO PROPAGATION MODEL
Before we introduce the shadowing model in this section we first introduce the free space
propagation model because it may be used to calculate the reference power in the shadowing
model. Besides, we will compare the free space loss model with the shadowing model in our
simulations.
The free space radio propagation model assumes, as its name indicates, that the transmitter and
the receiver are in free space without obstacles. The propagation formula is as follows [10]:
22
λd
AA
PP tr
tr = (1)
where rP is the signal power at the receiving antenna, tP is the signal power at the transmitting
antenna, rA is the effective area of the receiving antenna, tA is the effective area of the
transmitting antenna, d is the distance between the transmitting antenna and the receiving
antenna, and λ is the wavelength of the signal.
The effective area of an isotropic antenna is πλ 4/ . Equation 1 thus becomes the following for
isotropic antennas:
2
2
)4( d
PP tr
π
λ
= (2)
3. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
105
Equation 1 becomes the following when the transmitting antenna and the receiving antenna have
an antenna gain that is not equal to 1:
2
2
)4( d
GGPP rttr
π
λ
= (3)
where tG is the antenna gain of the transmitting antenna and rG is the antenna gain of the
receiving antenna.
As noted in [10], Equations 1 to 3 only apply under the following condition:
λ
2
2a
d ≥ (4)
Where a is the largest linear dimension of either of the antennas.
Because of multipath propagation effects, in reality the received power at a receiving antenna is
not a deterministic function of the communication distance as shown in the free space loss model.
Instead, the received power fluctuates randomly versus time. The shadowing model [11] better
reflects this characteristic of the received signal power in reality than the free space loss model
introduced earlier. The path loss is usually expressed in dB as follows in the the shadowing
model:
[ ] [ ] dBdBrdBr X
d
d
dPdP +
−=
0
0 log10)()( β (5)
where 0d is a reference distance, β is the path loss exponent, dBX is a Gaussian random
variable having a zero mean and a standard deviation of dBδ . The typical values of β and δ are
shown in Tables 1 and 2, respectively.
Table 1 Typical value of β in different environment
Environment β
Outdoor, free space 2
Outdoor, shadowed urban area 2.7-5
In building, line-of-sight 1.6-1.8
In building, obstructed 4-6
Table 1 Typical value of δ in different environment
Environment δ
Outdoor 4-12
Office, hard partition 7
Office, soft partition 9.6
Factory, line-of-sight 3-6
Factory, obstructed 6.8
4. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
106
3. SIMULATION RESULTS
In this section we study the shadowing model in UAV networks using the ns2 simulation
package. We also compare this model with the free space propagation model in this section. The
simulation package ns2 does not support simulations of three dimensional networks readily. We
modified the code for simulating UAV networks.
The test bed used in our simulations is shown in Figure 1, which has the same size of 500 meters
for its width, length, and height. UAVs fly freely in this defined space following the random
waypoint model. The UAVs in the test bed use the IEEE 802.11 air interface and default settings
are used in the simulations. For traffic, each UAV sets up a CBR connection with another UAV at
a random time in the duration of each simulation. A CBR source has a packet rate of 10 packets
per second and the size of each packet is 512 bytes. The UAVs use the DSR routing protocol [12]
in the test bed.
Figure 1 The simulated test bed
In our simulations we tested the shadowing model with varying node densities in the test bed and
compared it with the free space propagation model. In particular, for each model we varied the
number of nodes in the test bed from 10 to 50 in our simulations of UAV networks. In each
simulation we gathered data to calculate the average throughput and the average packet loss rate
of the CBR flows in the network. We also gathered data on the packet delay distributions in the
network. The simulation results comparing the two models are shown in Figures 2 to 9.
As shown in Figure 2, the average flow throughput in the network decreases as the node density
increases in the network. This decrease of flow throughput is mainly caused by two factors. One
is that the total traffic rate is higher in the network when there are more nodes in the network
because each node starts a CBR flow at a random time in each simulation. The other factor is that
the contention at the medium access control (MAC) layer is also higher when there are more
nodes in the network. The throughput results are also corroborated by the packet loss rate shown
in Figure 3. As shown in Figure 3, a higher node density in the network results in a higher packet
loss rate in the network.
5. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
107
As also shown in Figures 2 and 3, both the flow throughput trend and the packet loss rate trend
are consistent for the two propagation models. However, the throughput for the shadowing model
is significantly lower as compared with that of the free space model. The difference can reach
about thirty percent when the node density is low. When the node density is high, however, the
difference is smaller because the network becomes very congested in such a case and lots of
packet are dropped for both models. Similar observations can be made in Figure 3 for packet
losses for the two models.
Figure 2. The average flow rate for the two propagation models
Figure 3. The average packet loss rate for the two propagation models
The packet delay data shown in Figures 4 and 5 for the case of ten nodes in the test bed also
corroborate the results shown in earlier figures for the two models. As shown by Figures 4 and 5,
most packets have a delay within 0.2 second for the free space propagation model. For the
shadowing model, however, much more packets have a delay beyond 0.2 second. These packet
delay results are consistent with the throughput and loss results shown earlier.
6. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
108
Figure 4. The histogram of the packet delays for the free space loss model
Figure 5. The histogram of the packet delays for the shadowing loss model
After showing the results comparing the shadowing model with the free space model, we now
present more results on the shadowing model. Figures 6 and 7 show the average flow rate and the
average packet loss rate, respectively, in the test bed of ten nodes for the model. The horizontal
axis in these two figures is the δ parameter of the shadowing model, which reflects the severity
of the multipath effects on the links. As shown in Figure 6, the average flow throughput decreases
as δ increases. In particular, when δ increases from 2 to 12 the throughput decreases from above
18000 bps to below 8000 bps. The packet loss results in Figure 7 show results that are consistent
with the throughput results. A higher δ , which means higher multipath effects, results in a lower
average flow throughput and a higher average packet loss rate.
7. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
109
Figure 6. The average flow rate for the shadowing model with varyingδ
Figure 7. The average packet loss rate for the shadowing model with varyingδ
Figures 8 and 9 present the average flow rate and the average packet loss rate, respectively,
versus the β parameter of the shadowing model, which reflects the severity of the path loss. As
shown in Figure 8, the average flow throughput decreases rapidly as β increases even slowly. In
particular, when β increases from 2 to 2.6 the throughput decreases from above 18000 bps to
almost zero bps. The packet loss results presented in Figure 9 shows results that are also
consistent with the throughput results. A higher β , which means a higher path loss, results in a
lower average flow throughput and a higher average packet loss rate. When β reaches 2.6 in the
test bed, the packet loss rate reaches almost one hundred percent.
8. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
110
Figure 8. The average flow rate for the shadowing model with varying β
Figure 9. The average packet loss rate for the shadowing model with varying β
In summary, the choice of a radio propagation model in the simulation of an UAV network does
have a significant impact on the performance of the network. Moreover, the choice of the
parameters of a model are also important in simulating a UAV network, as shown by our study of
the shadowing model with varying parameters. We also found, however, that even the shadowing
model had simulation results very different from what the free space model had in each specific
case of simulation, the trend of the simulation results observed as a whole did show consistency
for the two models that we studied.
9. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
111
4.CONCLUSIONS
We investigated the shadowing radio propagation model in UAV networks using the ns2 network
simulation package. Our investigation shows that the shadowing model may generate simulation
results that are significantly different from those of the free space loss model in each specific case
of simulation. Particularly, the flow throughput, the packet loss rate, and the packet delays
consistently show much lower performance for the shadowing model than for the free space
model. However, our results also show that when the simulation results are observed as a whole,
the trend of flow throughput, packet loss rate, and packet delays is consistent for the two models.
We also found that the choice of the parameters of the shadowing propagation model is
significant in terms of network performance. Our conclusion is that the choice of a radio
propagation model and its parameters in simulating an UAV network does have significant
impact on the simulation results for each individual case of simulation, although the choice does
not affect the interpretation of the data when performance trend is the only concern of
investigation.
ACKNOWLEDGEMENTS
The authors would like to thank everyone who offered support to this project and the publication
of its results.
REFERENCES
[1] T. H. Cox, C. J. Nagy, M. A. Skoog, and I. A. Somers, “Civil UAV Capability Assessment,” NASA,
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[2] M. Asadpour, D. Giustiniano, K. A. Hummel, and S. Heimlicher, “Characterizing 802.11N Aerial
Communication,” in Proceedings of the Second ACM MobiHoc Workshop on Airborne Networks
and Communications, 2013, pp. 7–12.
[3] Y. Cai, F. Yu, J. Li, Y. Zhou, and L. Lamont, “Medium Access Control for Unmanned Aerial Vehicle
(UAV) Ad-Hoc Networks With Full-Duplex Radios and Multipacket Reception Capability,”
Vehicular Technology, IEEE Transactions on, vol. 62, pp. 390–394, Jan 2013.
[4] A. Ollero, M. Bernard, M. La Civita, L. van Hoesel, P. Marron, J. Lepley, and E. de Andres,
“AWARE: Platform for Autonomous self-deploying and operation of Wireless sensor-actuator
networks cooperating with unmanned AeRial vehiclEs,” in Safety, Security and Rescue Robotics,
2007, IEEE International Workshop on, Sept 2007, pp. 1–6.
[5] A. Alshbatat and L. Dong, “Adaptive MAC protocol for UAV communication networks using
directional antennas,” in Networking, Sensing and Control (ICNSC), 2010 International Conference
on, April 2010, pp. 598–603.
[6] A. Alshbatat and L. Dong, “Cross layer design for mobile Ad-Hoc Unmanned Aerial Vehicle
communication networks,” in Networking, Sensing and Control (ICNSC), 2010 International
Conference on, April 2010, pp. 331–336.
[7] D. Gu, G. Pei, H. Ly, M. Gerla, and X. Hong, “Hierarchical routing for multi-layer ad-hoc wireless
networks with UAVs,” in MILCOM 2000, vol. 1, 2000, pp. 310–314.
[8] D. Gu, H. Ly, X. Hong, M. Gerla, G. Pei, and Y.-Z. Lee, “C-ICAMA, a centralized intelligent channel
assigned multiple access for multi-layer ad-hoc wireless networks with UAVs,” in Wireless
Communications and Networking Conference, 2000, IEEE, vol. 2, 2000, pp. 879–884.
[9] The network simulator - ns-2. [Online]. Available: http://www.isi.edu/nsnam/ns/
[10] H. T. Friis, “A note on a simple transmission formula,” in Proceedings of the I.R.E. and Waves and
Electrons, 1946, pp. 254–256.
[11] T. S. Rappaport, “Wireless Communications, Principles and Practice,” Prentice Hall, 1996.
[12] D. B. Johnson, D. A. Maltz, and Y.-C. Hu, “The Dynamic Source Routing Protocol for Mobile Ad
Hoc Networks (DSR),” IETF Interet draft,draft-ietf-manet-dsr-10.txt, July 2004.
10. International Journal of Wireless & Mobile Networks (IJWMN) Vol. 7, No. 4, August 2015
112
Authors
Jun Peng received his Ph.D. degree from the Department of Electrical, Computer & Systems Engineering at
Rensselaer Polytechnic Institute, Troy, New York, United States. He is currently an associate professor at
the Electrical Engineering Department of University of Texas – Rio Grande Valley, Edinburg, Texas,
United States. His research interests are in computer and communication networks.