This document summarizes a research paper that proposes a novel buffer-aided relay selection scheme with significantly reduced packet delay for cooperative networks. The key points are:
1) Existing buffer-aided relay selection schemes improve outage performance but increase average packet delay linearly with relay number and buffer size.
2) The proposed scheme aims to reduce delay by giving higher priority to selecting relay-to-destination links over source-to-relay links, keeping data queues at relay buffers as short as possible.
3) The paper analyzes the outage probability, average packet delay, and asymptotic performance of the proposed scheme, and provides simulation results to verify the analysis. The scheme achieves significant gain in outage performance with similar
Fuzzy Optimized Metric for Adaptive Network RoutingCSCJournals
Network routing algorithms used today calculate least cost (shortest) paths between nodes. The cost of a path is the sum of the cost of all links on that path. The use of a single metric for adaptive routing is insufficient to reflect the actual state of the link. In general, there is a limitation on the accuracy of the link state information obtained by the routing protocol. Hence it becomes useful if two or more metrics can be associated to produce a single metric that can describe the state of the link more accurately. In this paper, a fuzzy inference rule base is implemented to generate the fuzzy cost of each candidate path to be used in routing the incoming calls. This fuzzy cost is based on the crisp values of the different metrics; a fuzzy membership function is defined. The parameters of these membership functions reflect dynamically the requirement of the incoming traffic service as well as the current state of the links in the path. And this paper investigates how three metrics, the mean link bandwidth, queue utilization and the mean link delay, can be related using a simple fuzzy logic algorithm to produce a optimized cost of the link for a certain interval that is more „precise‟ than either of the single metric, to solve routing problem .
IOSR Journal of Computer Engineering (IOSR-JCE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of computer engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in computer technology. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
On minimizing data forwarding schedule in multi transmit receive wireless mes...redpel dot com
On minimizing data forwarding schedule in multi transmit receive wireless mesh network
for more ieee paper / full abstract / implementation , just visit www.redpel.com
Impact of le arrivals and departures on bufferingenioustech
Dear Students
Ingenious techno Solution offers an expertise guidance on you Final Year IEEE & Non- IEEE Projects on the following domain
JAVA
.NET
EMBEDDED SYSTEMS
ROBOTICS
MECHANICAL
MATLAB etc
For further details contact us:
enquiry@ingenioustech.in
044-42046028 or 8428302179.
Ingenious Techno Solution
#241/85, 4th floor
Rangarajapuram main road,
Kodambakkam (Power House)
http://www.ingenioustech.in/
A New Efficient Cache Replacement Strategy for Named Data NetworkingIJCNCJournal
The Information-Centric Network (ICN) is a future internet architecture with efficient content retrieval and distribution. Named Data Networking (NDN) is one of the proposed architectures for ICN. NDN’s innetwork caching improves data availability, reduce retrieval delays, network load, alleviate producer load, and limit data traffic. Despite the existence of several caching decision algorithms, the fetching and distribution of contents with minimum resource utilization remains a great challenge. In this paper, we introduce a new cache replacement strategy called Enhanced Time and Frequency Cache Replacement strategy (ETFCR) where both cache hit frequency and cache retrieval time are used to select evicted data chunks. ETFCR adds time cycles between the last two requests to adjust data chunk’s popularity and cache hits. We conducted extensive simulations using the ccnSim simulator to evaluate the performance of ETFCR and compare it to that of some well-known cache replacement strategies. Simulations results show that ETFCR outperforms the other cache replacement strategies in terms of cache hit ratio, and lower content retrieval delay.
Energy of Bandwidth and Storage Routing Protocol for Opportunistic NetworksEswar Publications
Opportunistic Networks is communication environment which has no stable path. Therefore, in this environment, the routing algorithms are partitioned into two main classes which are metric-based and contact-based. Essentially, contact based algorithms target for a high routing performance and small delay at the same time. However; these protocols consume high resources in terms of Energy, Bandwidth and Storage. Practically, opportunistic nodes such as smart phones and tablets suffer from the limitation of the energy and physical
memory. In addition, the environment connectivity instability leads to low bandwidth links. This work proposes a resource concentrate routing protocol for opportunistic networks, named Energy of Bandwidth and Storage Routing Protocol (EBSRP). The energy is considered as a main factor calculated as a function of bandwidth and storage. The proposed EBSRP has its queuing policy calculated as a function of energy ratio. The Simulation results are used to analyze the performance of EBSRP and it is compared with Epidemic using different
replication and dropping policies based on energy, bandwidth, and storage. The results show that the proposed protocol has better performance than Epidemic in terms of delivery ratio, delay, and overhead.
Fuzzy Optimized Metric for Adaptive Network RoutingCSCJournals
Network routing algorithms used today calculate least cost (shortest) paths between nodes. The cost of a path is the sum of the cost of all links on that path. The use of a single metric for adaptive routing is insufficient to reflect the actual state of the link. In general, there is a limitation on the accuracy of the link state information obtained by the routing protocol. Hence it becomes useful if two or more metrics can be associated to produce a single metric that can describe the state of the link more accurately. In this paper, a fuzzy inference rule base is implemented to generate the fuzzy cost of each candidate path to be used in routing the incoming calls. This fuzzy cost is based on the crisp values of the different metrics; a fuzzy membership function is defined. The parameters of these membership functions reflect dynamically the requirement of the incoming traffic service as well as the current state of the links in the path. And this paper investigates how three metrics, the mean link bandwidth, queue utilization and the mean link delay, can be related using a simple fuzzy logic algorithm to produce a optimized cost of the link for a certain interval that is more „precise‟ than either of the single metric, to solve routing problem .
IOSR Journal of Computer Engineering (IOSR-JCE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of computer engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in computer technology. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
On minimizing data forwarding schedule in multi transmit receive wireless mes...redpel dot com
On minimizing data forwarding schedule in multi transmit receive wireless mesh network
for more ieee paper / full abstract / implementation , just visit www.redpel.com
Impact of le arrivals and departures on bufferingenioustech
Dear Students
Ingenious techno Solution offers an expertise guidance on you Final Year IEEE & Non- IEEE Projects on the following domain
JAVA
.NET
EMBEDDED SYSTEMS
ROBOTICS
MECHANICAL
MATLAB etc
For further details contact us:
enquiry@ingenioustech.in
044-42046028 or 8428302179.
Ingenious Techno Solution
#241/85, 4th floor
Rangarajapuram main road,
Kodambakkam (Power House)
http://www.ingenioustech.in/
A New Efficient Cache Replacement Strategy for Named Data NetworkingIJCNCJournal
The Information-Centric Network (ICN) is a future internet architecture with efficient content retrieval and distribution. Named Data Networking (NDN) is one of the proposed architectures for ICN. NDN’s innetwork caching improves data availability, reduce retrieval delays, network load, alleviate producer load, and limit data traffic. Despite the existence of several caching decision algorithms, the fetching and distribution of contents with minimum resource utilization remains a great challenge. In this paper, we introduce a new cache replacement strategy called Enhanced Time and Frequency Cache Replacement strategy (ETFCR) where both cache hit frequency and cache retrieval time are used to select evicted data chunks. ETFCR adds time cycles between the last two requests to adjust data chunk’s popularity and cache hits. We conducted extensive simulations using the ccnSim simulator to evaluate the performance of ETFCR and compare it to that of some well-known cache replacement strategies. Simulations results show that ETFCR outperforms the other cache replacement strategies in terms of cache hit ratio, and lower content retrieval delay.
Energy of Bandwidth and Storage Routing Protocol for Opportunistic NetworksEswar Publications
Opportunistic Networks is communication environment which has no stable path. Therefore, in this environment, the routing algorithms are partitioned into two main classes which are metric-based and contact-based. Essentially, contact based algorithms target for a high routing performance and small delay at the same time. However; these protocols consume high resources in terms of Energy, Bandwidth and Storage. Practically, opportunistic nodes such as smart phones and tablets suffer from the limitation of the energy and physical
memory. In addition, the environment connectivity instability leads to low bandwidth links. This work proposes a resource concentrate routing protocol for opportunistic networks, named Energy of Bandwidth and Storage Routing Protocol (EBSRP). The energy is considered as a main factor calculated as a function of bandwidth and storage. The proposed EBSRP has its queuing policy calculated as a function of energy ratio. The Simulation results are used to analyze the performance of EBSRP and it is compared with Epidemic using different
replication and dropping policies based on energy, bandwidth, and storage. The results show that the proposed protocol has better performance than Epidemic in terms of delivery ratio, delay, and overhead.
Authentication of Secure Data Transmission In Wireless RoutingIJERA Editor
The major objective of our work is to explore a security enhanced dynamic routing algorithm based on distributed routing information widely supported in existing wired and wireless networks. The message authentication is the main area to be considered in WSN’s. Most of the wireless networks are attacked for detecting the data’s that are transmitted in between the users. We aim at the randomization of delivery paths for data transmission to provide considerably small path similarity (i.e., the number of common links between two delivery paths) of two consecutive transmitted packets. The proposed algorithm should be easy to implement and compatible with popular routing protocols, such as the Routing Information Protocol (RIP) for wired networks and Destination-Sequenced Distance Vector (DSDV) protocol for wireless networks over existing infrastructures. These protocols shall not increase the number of control messages if the proposed algorithm is adopted. An analytic study will be presented for the proposed routing algorithm, and a series of simulation study will be conducted to verify the analytic results and to show the capability of the proposed algorithm.
SECTOR TREE-BASED CLUSTERING FOR ENERGY EFFICIENT ROUTING PROTOCOL IN HETEROG...IJCNCJournal
One of the main challenges for researchers to build routing protocols is how to use energy efficiently to extend the lifespan of the whole wireless sensor networks (WSN) because sensor nodes have limited battery power resources. In this work, we propose a Sector Tree-Based clustering routing protocol (STB-EE) for Energy Efficiency to cope with this problem, where the entire network area is partitioned into dynamic sectors (clusters), which balance the number of alive nodes. The nodes in each sector only communicate with their nearest neighbour by constructing a minimum tree based on the Kruskal algorithm and using mixed distance from candidate node to base station (BS) and remaining energy of candidate nodes to determine which node will become the cluster head (CH) in each cluster? By calculating the duration of time in each round for suitability, STB-EE increases the number of data packets sent to the BS. Our simulation results show that the network lifespan using STB-EE can be improved by about 16% and 10% in comparison to power-efficient gathering in sensor information system (PEGASIS) and energy-efficient PEGASIS-based protocol (IEEPB), respectively.
On the routing overhead in infrastructureless multihop wireless networksNarendra Singh Yadav
Routing in infrastructureless multihop wireless networks is a challenging task and has received a vast amount of attention from researchers. This has lead to development of many different routing protocols each having their own superiorities and pitfalls making it very difficult to decide on a better protocol under vulnerable scenarios in such networks. In this paper the performance of three routing protocols (DSR, AODV and CBRP) in terms of routing overhead in bytes and in packets is presented under growing density and varying mobility in different traffic conditions. The simulation results show that CBRP outperforms both DSR and AODV in all scenarios.
AN EFFECTIVE CONTROL OF HELLO PROCESS FOR ROUTING PROTOCOL IN MANETSIJCNCJournal
In the mobile ad hoc network (MANET) update of link connectivity is necessary to refresh the neighbor tables in data transfer. A existing hello process periodically exchanges the link connectivity information, which is not adequate for dynamic topology. Here, slow update of neighbour table entries causes link failures which affect performance parameter as packet drop, maximum delay, energy consumption, and reduced throughput. In the dynamic hello technique, new neighbour nodes and lost neighbour nodes are used to compute link change rate (LCR) and hello-interval/refresh rate (r). Exchange of link connectivity information at a fast rate consumes unnecessary bandwidth and energy. In MANET resource wastage can be controlled by avoiding the re-route discovery, frequent error notification, and local repair in the entire network. We are enhancing the existing hello process, which shows significant improvement in performance.
FAULT-TOLERANT MULTIPATH ROUTING SCHEME FOR ENERGY EFFICIENT WIRELESS SENSOR ...ijwmn
Themain challengein wireless sensor network is to improve the fault tolerance of each
node and also provide an energy efficient fast data routing service. In this paper we propose an
energyefficient node fault diagnosis and recovery for wireless sensor networks referred as fault tolerant
multipath routing scheme for energy efficientwireless sensor network (FTMRS).The FTMRSis based on
multipath data routing scheme. One shortest path is use for main data routing in FTMRS technique and
other two backup paths are used as alternative path for faulty network and to handle the overloaded
traffic on main channel.Shortest path data routing ensures energy efficient data routing. The
performance analysis of FTMRSshows better results compared to other popular fault tolerant techniques
in wireless sensor networks.
New strategy to optimize the performance of spray and wait routing protocolijwmn
Delay Tolerant Networks have been (DTN) have been developed to support the irregular connectivity often
separate networks. The main routing problem in this type of network is embarrassed by time that is
extremely long, since connections are intermittent and opportunistic. Routing protocols must take into
account the maximum constraint encountered in this type of environment , use effective strategies
regarding the choice of relay nodes and buffer management nodes to improve the delivery of messages and
the time of their delivery . This article proposes a new strategy that optimizes the routing Spray and wait.
The proposed method uses the information contained in the messages delivered mostly paths traversed by
the messages before arriving at their destination and the time when nodes have receive these messages.
Simulation results show that the proposed strategy can increase the probability of delivery and minimizing
overhead unlike FIFO technology used with the default routing ' sprat and wait'
Enforcing end to-end proportional fairness with bounded buffer overflow proba...ijwmn
In this paper, we present a distributed flow-based
access scheme for slotted-time protocols, that prov
ides
proportional fairness in ad-hoc wireless networks u
nder constraints on the buffer overflow probabiliti
es at
each node. The proposed scheme requires local infor
mation exchange at the link-layer and end-to-end
information exchange at the transport-layer, and is
cast as a nonlinear program. A medium access contr
ol
protocol is said to be proportionally fair with res
pect to individual end-to-end flows in a network, i
f the
product of the end-to-end flow rates is maximized.
A key contribution of this work lies in the constru
ction of
a distributed dual approach that comes with low com
putational overhead. We discuss the convergence
properties of the proposed scheme and present simul
ation results to support our conclusions.
Analysis of multi hop relay algorithm for efficient broadcasting in manetseSAT 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
Fuzzy Controller Based Stable Routes with Lifetime Prediction in MANETsCSCJournals
In ad hoc networks, the nodes are dynamically and arbitrary located in a manner that the interconnections between nodes are changing frequently. Thus, designing an effective routing protocol is a critical issue. In this paper, we propose a fuzzy based routing method that selects the most stable route (FSRS) considering the number of intermediate nodes, packet queue occupancy, and internodes distances. Also it takes the produced cost of the selected route as an input to another fuzzy controller predicts its lifetime (FRLP), the evaluation of the proposed method is performed using OMNet++4.0 simulator in terms of packet delivery ratio, average end-to-end delay and normalized routing load.
SCTP-MANET NEW EXTENSION OF SCTP PROTOCOL FOR THE OPTIMIZATION OF MANET PERFO...ijwmn
Ad Hoc mobile networks are constituted of nodes that move freely without a centralized administration.
These nodes contribute in the routing of data packets that are sent by a source. This happens when the
latter is not capable of reaching its destination. On the other hand, their mobility causes recurrent
breakdowns of the routing paths notably with sparse MANET. In order to optimize the performance of such
networks, we suggest a new extension of protocols: Stream Control Transmission Protocols (SCTP) named
SCTP-MANET. Their main function is therefore to improve the availability of the links in sparse MANET
protocols. This could be achieved by a better integration of Multihoming. With this aim in mind, this new
extension is based on a cross-layer interface between transport and routing layers as well as the use of
specific messages.
Cost Effective Routing Protocols Based on Two Hop Neighborhood Information (2...Eswar Publications
Ad hoc networks are collections of mobile nodes communicating with each other using wireless media without any fixed infrastructure. During both route discovery and traversal of route-reply packets from destination to source,
broadcast of packets is required which incurs huge message cost. The present article deals with the message cost
reduction during transmission of route-reply from destination to source. Also the redundancy that is visible within the 2-hop neighborhood of a node is minimized during broadcasting of route-reply. This improves the average lifetime of network nodes by decreasing the possibility of network partition. The scheme of 2NI can be used with any reactive routing protocol in MANETs.
Impact of energy and link quality indicator with link quality estimators in w...graphhoc
The Link Quality Indicator (LQI) and Residual Energy have a fundamental impact on the network
performance in Wireless Sensor Networks (WSNs) and affects as well in the life time of nodes. This paper
will provide a comparative of Link Quality Estimator, the Link Quality Estimator with Link Quality
Indicator and Link Quality Estimator with Residual Energy. In this paper we develop a Collect Tree
Protocol (CTP) and compare the performance of LQI and Residual Energy, and show their effect on the
packet delivery ratio and throughput, covering the characteristics of low-power links, and their
performance to the best of our knowledge, we believe that our efforts would have implementations on
embedded application.
Delay Tolerant Network (DTN) is a promising technology which aims to provide efficient
communication between devices in a network with no guaranteed continuous connectivity. Most
of the existing routing schemes for DTNs achieve message delivery through message replication
and forwarding. However, due to the lack of contemporaneous end-to-end communication path,
designing routing protocols that can achieve high delivery rate with low communication
overhead is a challenging problem. Some routing protocols appear with high similarity, but
their performance are significantly different. In this paper, we evaluate several popular routing
protocols in DTNs, including Epidemic, Spray and Wait, PRoPHET, and 3R through extensive
trace-driven simulations. The objective is to evaluate the performance of different routing
schemes using different data traces and investigate the optimal configuration setting for each
routing scheme. This paper provides important guidances on the design and selection of routing
protocols for given delay tolerant networks.
Intra and inter-fractional variation prediction of lung tumors using fuzzy d...redpel dot com
Intra and inter-fractional variation prediction of lung tumors using fuzzy deep learning
for more ieee paper / full abstract / implementation , just visit www.redpel.com
Authentication of Secure Data Transmission In Wireless RoutingIJERA Editor
The major objective of our work is to explore a security enhanced dynamic routing algorithm based on distributed routing information widely supported in existing wired and wireless networks. The message authentication is the main area to be considered in WSN’s. Most of the wireless networks are attacked for detecting the data’s that are transmitted in between the users. We aim at the randomization of delivery paths for data transmission to provide considerably small path similarity (i.e., the number of common links between two delivery paths) of two consecutive transmitted packets. The proposed algorithm should be easy to implement and compatible with popular routing protocols, such as the Routing Information Protocol (RIP) for wired networks and Destination-Sequenced Distance Vector (DSDV) protocol for wireless networks over existing infrastructures. These protocols shall not increase the number of control messages if the proposed algorithm is adopted. An analytic study will be presented for the proposed routing algorithm, and a series of simulation study will be conducted to verify the analytic results and to show the capability of the proposed algorithm.
SECTOR TREE-BASED CLUSTERING FOR ENERGY EFFICIENT ROUTING PROTOCOL IN HETEROG...IJCNCJournal
One of the main challenges for researchers to build routing protocols is how to use energy efficiently to extend the lifespan of the whole wireless sensor networks (WSN) because sensor nodes have limited battery power resources. In this work, we propose a Sector Tree-Based clustering routing protocol (STB-EE) for Energy Efficiency to cope with this problem, where the entire network area is partitioned into dynamic sectors (clusters), which balance the number of alive nodes. The nodes in each sector only communicate with their nearest neighbour by constructing a minimum tree based on the Kruskal algorithm and using mixed distance from candidate node to base station (BS) and remaining energy of candidate nodes to determine which node will become the cluster head (CH) in each cluster? By calculating the duration of time in each round for suitability, STB-EE increases the number of data packets sent to the BS. Our simulation results show that the network lifespan using STB-EE can be improved by about 16% and 10% in comparison to power-efficient gathering in sensor information system (PEGASIS) and energy-efficient PEGASIS-based protocol (IEEPB), respectively.
On the routing overhead in infrastructureless multihop wireless networksNarendra Singh Yadav
Routing in infrastructureless multihop wireless networks is a challenging task and has received a vast amount of attention from researchers. This has lead to development of many different routing protocols each having their own superiorities and pitfalls making it very difficult to decide on a better protocol under vulnerable scenarios in such networks. In this paper the performance of three routing protocols (DSR, AODV and CBRP) in terms of routing overhead in bytes and in packets is presented under growing density and varying mobility in different traffic conditions. The simulation results show that CBRP outperforms both DSR and AODV in all scenarios.
AN EFFECTIVE CONTROL OF HELLO PROCESS FOR ROUTING PROTOCOL IN MANETSIJCNCJournal
In the mobile ad hoc network (MANET) update of link connectivity is necessary to refresh the neighbor tables in data transfer. A existing hello process periodically exchanges the link connectivity information, which is not adequate for dynamic topology. Here, slow update of neighbour table entries causes link failures which affect performance parameter as packet drop, maximum delay, energy consumption, and reduced throughput. In the dynamic hello technique, new neighbour nodes and lost neighbour nodes are used to compute link change rate (LCR) and hello-interval/refresh rate (r). Exchange of link connectivity information at a fast rate consumes unnecessary bandwidth and energy. In MANET resource wastage can be controlled by avoiding the re-route discovery, frequent error notification, and local repair in the entire network. We are enhancing the existing hello process, which shows significant improvement in performance.
FAULT-TOLERANT MULTIPATH ROUTING SCHEME FOR ENERGY EFFICIENT WIRELESS SENSOR ...ijwmn
Themain challengein wireless sensor network is to improve the fault tolerance of each
node and also provide an energy efficient fast data routing service. In this paper we propose an
energyefficient node fault diagnosis and recovery for wireless sensor networks referred as fault tolerant
multipath routing scheme for energy efficientwireless sensor network (FTMRS).The FTMRSis based on
multipath data routing scheme. One shortest path is use for main data routing in FTMRS technique and
other two backup paths are used as alternative path for faulty network and to handle the overloaded
traffic on main channel.Shortest path data routing ensures energy efficient data routing. The
performance analysis of FTMRSshows better results compared to other popular fault tolerant techniques
in wireless sensor networks.
New strategy to optimize the performance of spray and wait routing protocolijwmn
Delay Tolerant Networks have been (DTN) have been developed to support the irregular connectivity often
separate networks. The main routing problem in this type of network is embarrassed by time that is
extremely long, since connections are intermittent and opportunistic. Routing protocols must take into
account the maximum constraint encountered in this type of environment , use effective strategies
regarding the choice of relay nodes and buffer management nodes to improve the delivery of messages and
the time of their delivery . This article proposes a new strategy that optimizes the routing Spray and wait.
The proposed method uses the information contained in the messages delivered mostly paths traversed by
the messages before arriving at their destination and the time when nodes have receive these messages.
Simulation results show that the proposed strategy can increase the probability of delivery and minimizing
overhead unlike FIFO technology used with the default routing ' sprat and wait'
Enforcing end to-end proportional fairness with bounded buffer overflow proba...ijwmn
In this paper, we present a distributed flow-based
access scheme for slotted-time protocols, that prov
ides
proportional fairness in ad-hoc wireless networks u
nder constraints on the buffer overflow probabiliti
es at
each node. The proposed scheme requires local infor
mation exchange at the link-layer and end-to-end
information exchange at the transport-layer, and is
cast as a nonlinear program. A medium access contr
ol
protocol is said to be proportionally fair with res
pect to individual end-to-end flows in a network, i
f the
product of the end-to-end flow rates is maximized.
A key contribution of this work lies in the constru
ction of
a distributed dual approach that comes with low com
putational overhead. We discuss the convergence
properties of the proposed scheme and present simul
ation results to support our conclusions.
Analysis of multi hop relay algorithm for efficient broadcasting in manetseSAT 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
Fuzzy Controller Based Stable Routes with Lifetime Prediction in MANETsCSCJournals
In ad hoc networks, the nodes are dynamically and arbitrary located in a manner that the interconnections between nodes are changing frequently. Thus, designing an effective routing protocol is a critical issue. In this paper, we propose a fuzzy based routing method that selects the most stable route (FSRS) considering the number of intermediate nodes, packet queue occupancy, and internodes distances. Also it takes the produced cost of the selected route as an input to another fuzzy controller predicts its lifetime (FRLP), the evaluation of the proposed method is performed using OMNet++4.0 simulator in terms of packet delivery ratio, average end-to-end delay and normalized routing load.
SCTP-MANET NEW EXTENSION OF SCTP PROTOCOL FOR THE OPTIMIZATION OF MANET PERFO...ijwmn
Ad Hoc mobile networks are constituted of nodes that move freely without a centralized administration.
These nodes contribute in the routing of data packets that are sent by a source. This happens when the
latter is not capable of reaching its destination. On the other hand, their mobility causes recurrent
breakdowns of the routing paths notably with sparse MANET. In order to optimize the performance of such
networks, we suggest a new extension of protocols: Stream Control Transmission Protocols (SCTP) named
SCTP-MANET. Their main function is therefore to improve the availability of the links in sparse MANET
protocols. This could be achieved by a better integration of Multihoming. With this aim in mind, this new
extension is based on a cross-layer interface between transport and routing layers as well as the use of
specific messages.
Cost Effective Routing Protocols Based on Two Hop Neighborhood Information (2...Eswar Publications
Ad hoc networks are collections of mobile nodes communicating with each other using wireless media without any fixed infrastructure. During both route discovery and traversal of route-reply packets from destination to source,
broadcast of packets is required which incurs huge message cost. The present article deals with the message cost
reduction during transmission of route-reply from destination to source. Also the redundancy that is visible within the 2-hop neighborhood of a node is minimized during broadcasting of route-reply. This improves the average lifetime of network nodes by decreasing the possibility of network partition. The scheme of 2NI can be used with any reactive routing protocol in MANETs.
Impact of energy and link quality indicator with link quality estimators in w...graphhoc
The Link Quality Indicator (LQI) and Residual Energy have a fundamental impact on the network
performance in Wireless Sensor Networks (WSNs) and affects as well in the life time of nodes. This paper
will provide a comparative of Link Quality Estimator, the Link Quality Estimator with Link Quality
Indicator and Link Quality Estimator with Residual Energy. In this paper we develop a Collect Tree
Protocol (CTP) and compare the performance of LQI and Residual Energy, and show their effect on the
packet delivery ratio and throughput, covering the characteristics of low-power links, and their
performance to the best of our knowledge, we believe that our efforts would have implementations on
embedded application.
Delay Tolerant Network (DTN) is a promising technology which aims to provide efficient
communication between devices in a network with no guaranteed continuous connectivity. Most
of the existing routing schemes for DTNs achieve message delivery through message replication
and forwarding. However, due to the lack of contemporaneous end-to-end communication path,
designing routing protocols that can achieve high delivery rate with low communication
overhead is a challenging problem. Some routing protocols appear with high similarity, but
their performance are significantly different. In this paper, we evaluate several popular routing
protocols in DTNs, including Epidemic, Spray and Wait, PRoPHET, and 3R through extensive
trace-driven simulations. The objective is to evaluate the performance of different routing
schemes using different data traces and investigate the optimal configuration setting for each
routing scheme. This paper provides important guidances on the design and selection of routing
protocols for given delay tolerant networks.
Intra and inter-fractional variation prediction of lung tumors using fuzzy d...redpel dot com
Intra and inter-fractional variation prediction of lung tumors using fuzzy deep learning
for more ieee paper / full abstract / implementation , just visit www.redpel.com
A cloud gaming system based on user level virtualization and its resource sch...redpel dot com
A cloud gaming system based on user level virtualization and its resource scheduling.
for more ieee paper / full abstract / implementation , just visit www.redpel.com
Privacy preserving and delegated access control for cloud applicationsredpel dot com
Privacy preserving and delegated access control for cloud applications
for more ieee paper / full abstract / implementation , just visit www.redpel.com
A hierarchical security framework for defending against sophisticated attacks...redpel dot com
A hierarchical security framework for defending against sophisticated attacks on wireless sensor networks in smart cities
for more ieee paper / full abstract / implementation , just visit www.redpel.com
Rate Adaptation for Time Varying Channels Using Distributed Relay Selectionpaperpublications3
Abstract: Fixed systems used in cooperative communication suffer from multiplexing loss and low spectral efficiency due to the half duplex constraint of relays. To improve the multiplexing gain, successive relaying is proposed. This allows concurrent transmission of the source and relays. However, the severe inter-relay interference becomes a key challenge. Here Rate Adaptation for Time Varying Channels Using Distributed Relay Selection is proposed, which is capable of adapting the relay’s rate using distributed relay selection.
Performance Analysis of Distributed Spatial Multiplexing with Multi-hop Ampli...IJCSEA Journal
This paper describes a frame work investigating the performance of distributed spatial multiplexing (DSM) in cooperative multi-hop cellular networks. The cooperative communication in cellular networks gives us leverage to get the inherent advantages of its random relay locations and the direction of the data flow. However, traditional centralized relay selection needs considerable overhead and signaling. In our proposed work, threshold based relay selection is adopted based on the received signal strength (RSS) and Signal to Noise Ratio (SNR). The best relay chosen will transmit jointly with source using Amplify and forward (AF) protocol. The evaluation is performed with bit error rate (BER) and energy per bit for distributed spatial multiplexing scheme with multi-hop networking.
Efficient and Fair Bandwidth Allocation AQM Scheme for Wireless NetworksCSCJournals
Heterogeneous Wireless Networks are considered nowadays as one of the potential areas in research and development. The traffic management’s schemes that have been used at the fusion points between the different wireless networks are classical and conventional. This paper is focused on developing a novel scheme to overcome the problem of traffic congestion in the fusion point router interconnected the heterogeneous wireless networks. The paper proposed an EF-AQM algorithm which provides an efficient and fair allocation of bandwidth among different established flows. Finally, the proposed scheme developed, tested and validated through a set of experiments to demonstrate the relative merits and capabilities of a proposed scheme
In wireless distributed sensor networks, one open problem is how to guarantee the reliable relay
selection based on the quality of services diversity. To address this problem, we focus on the reliable
adaptive relay selection approach and adaptive QoS supported algorithm, based on which we present a
Markov chain model, in consideration of different packet states and error control algorithm assignment.
The mathematical analyses and MATLAB simulation results show that the proposed relay selection
approach could perform better in terms of saturation throughput, reliability, and energy efficiency,
compared with the traditional approaches. More importantly, the quality of real-time multimedia streaming
is improved significantly, in terms of decodable frame ratio and delay.
Exploiting cooperative relay for high performance communications in mimo ad h...IEEEFINALYEARPROJECTS
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Multi-Hop Routing Cooperative Communication for Improving Throughput in IEEE ...IJERA Editor
In this paper, we propose cooperative communication scheme using multiple relays to improve the throughput of IEEE 802.11x wireless LAN. The proposed scheme performs cooperative communication with a terminal supporting a high data rate in order to solve the problem that a total network throughput is greatly reduced when a terminal supporting a low data rate occupies a channel. Also, the multi-hop routing is performed to optimize the performance of cooperative communication. According to the simulation results, the proposed cooperative communication scheme improves the reduction rate of the throughput even if the number of terminals supporting a low data rate increases in the entire network
An Improved Energy Efficient Wireless Sensor Networks Through Clustering In C...Editor IJCATR
One of the major reason for performance degradation in Wireless sensor network is the overhead due to control packet and
packet delivery degradation. Clustering in cross layer network operation is an efficient way manage control packet overhead and which
ultimately improve the lifetime of a network. All these overheads are crucial in a scalable networks. But the clustering always suffer
from the cluster head failure which need to be solved effectively in a large network. As the focus is to improve the average lifetime of
sensor network the cluster head is selected based on the battery life of nodes. The cross-layer operation model optimize the overheads
in multiple layer and ultimately the use of clustering will reduce the major overheads identified and their by the energy consumption
and throughput of wireless sensor network is improved. The proposed model operates on two layers of network ie., Network Layer
and Transport Layer and Clustering is applied in the network layer . The simulation result shows that the integration of two layers
reduces the energy consumption and increases the throughput of the wireless sensor networks.
An Improved Energy Efficient Wireless Sensor Networks Through Clustering In C...Editor IJCATR
One of the major reason for performance degradation in Wireless sensor network is the overhead due to control packet and
packet delivery degradation. Clustering in cross layer network operation is an efficient way manage control packet overhead and which
ultimately improve the lifetime of a network. All these overheads are crucial in a scalable networks. But the clustering always suffer
from the cluster head failure which need to be solved effectively in a large network. As the focus is to improve the average lifetime of
sensor network the cluster head is selected based on the battery life of nodes. The cross-layer operation model optimize the overheads
in multiple layer and ultimately the use of clustering will reduce the major overheads identified and their by the energy consumption
and throughput of wireless sensor network is improved. The proposed model operates on two layers of network ie., Network Layer
and Transport Layer and Clustering is applied in the network layer . The simulation result shows that the integration of two layers
reduces the energy consumption and increases the throughput of the wireless sensor networks.
An Improved Energy Efficient Wireless Sensor Networks Through Clustering In C...Editor IJCATR
One of the major reason for performance degradation in Wireless sensor network is the overhead due to control packet and packet delivery degradation. Clustering in cross layer network operation is an efficient way manage control packet overhead and which ultimately improve the lifetime of a network. All these overheads are crucial in a scalable networks. But the clustering always suffer from the cluster head failure which need to be solved effectively in a large network. As the focus is to improve the average lifetime of sensor network the cluster head is selected based on the battery life of nodes. The cross-layer operation model optimize the overheads in multiple layer and ultimately the use of clustering will reduce the major overheads identified and their by the energy consumption and throughput of wireless sensor network is improved. The proposed model operates on two layers of network ie., Network Layer and Transport Layer and Clustering is applied in the network layer . The simulation result shows that the integration of two layers reduces the energy consumption and increases the throughput of the wireless sensor networks.
An Improved Energy Efficient Wireless Sensor Networks Through Clustering In C...Editor IJCATR
One of the major reason for performance degradation in Wireless sensor network is the overhead due to control packet and packet delivery degradation. Clustering in cross layer network operation is an efficient way manage control packet overhead and which ultimately improve the lifetime of a network. All these overheads are crucial in a scalable networks. But the clustering always suffer from the cluster head failure which need to be solved effectively in a large network. As the focus is to improve the average lifetime of sensor network the cluster head is selected based on the battery life of nodes. The cross-layer operation model optimize the overheads in multiple layer and ultimately the use of clustering will reduce the major overheads identified and their by the energy consumption and throughput of wireless sensor network is improved. The proposed model operates on two layers of network ie., Network Layer and Transport Layer and Clustering is applied in the network layer . The simulation result shows that the integration of two layers reduces the energy consumption and increases the throughput of the wireless sensor networks.
LEACH is a hierarchical protocol in which most nodes transmit to cluster heads, and the cluster heads aggregate and compress the data and forward it to the base station (sink).In LEACH, a TDMA-based MAC protocol is integrated with clustering and a simple “routing” protocol. The goal of LEACH is to lower the energy consumption required to create and maintain clusters or to use the energy of the nodes in such a manner so as to improve the life time of a wireless sensor network. In this paper we are presenting an overview of the different protocol changes made in LEACH to improve network lifetime, throughput, coverage area of network etc.
LEACH is a hierarchical protocol in which most nodes transmit to cluster heads, and the cluster heads aggregate and
compress the data and forward it to the base station (sink).In LEACH, a TDMA-based MAC protocol is integrated with clustering and
a simple “routing” protocol. The goal of LEACH is to lower the energy consumption required to create and maintain clusters or to use
the energy of the nodes in such a manner so as to improve the life time of a wireless sensor network. In this paper we are presenting an
overview of the different protocol changes made in LEACH to improve network lifetime, throughput, coverage area of network etc.
Improvement In LEACH Protocol By Electing Master Cluster Heads To Enhance The...Editor IJCATR
In wireless sensor networks, sensor nodes play the most prominent role. These sensor nodes are mainly un-chargeable, so it
raises an issue regarding lifetime of the network. Mainly sensor nodes collect data and transmit it to the Base Station. So, most of the
energy is consumed in the communication process between sensor nodes and the Base Station. In this paper, we present an
improvement on LEACH protocol to enhance the network lifetime. Our goal is to reduce the transmissions between cluster heads and
the sink node. We will choose optimum number of Master Cluster Heads from variation cluster heads present in the network. The
simulation results show that our proposed algorithm enhances the network lifetime as compare to the LEACH protocol.
Transfer reliability and congestion control strategies in opportunistic netwo...IEEEFINALYEARPROJECTS
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INCREASE THE LIFETIME OF WIRELESS SENSOR NETWORKS USING HIERARCHICAL CLUSTERI...ijwmn
Wireless sensor networks consist of hundreds or thousands of nodes with limited energy. Since the life time
of each sensor is equivalent to the battery life, the energy issue is considered as a major challenge.
Clustering has been proposed as a strategy to extend the lifetime of wireless sensor networks. Cluster size,
number of Cluster head per cluster and the selection of cluster head are considered as important factors in
clustering. In this research by studying LEACH algorithm and optimized algorithms of this protocol and by
evaluating the strengths and weaknesses, a new algorithm based on hierarchical clustering to increase the
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network is layered and the optimal number of cluster head in each layer is selected and then recruit for the
formation of clusters in the same layer by controlling the topology of the clusters is done independently.
Then the data is sent through the by cluster heads through the multi- stage to the main station. Simulation
results show that the above mentioned method increases the life time about 70% compared to the LEACH.
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Buffer aided relay selection with reduced packet delay in cooprative network
1. This work is licensed under a Creative Commons Attribution 3.0 License. For more information, see http://creativecommons.org/licenses/by/3.0/.
This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Citation information: DOI 10.1109/TVT.2016.2573378, IEEE
Transactions on Vehicular Technology
Buffer-aided Relay Selection with Reduced Packet
Delay in Cooperative Networks
Zhao Tian, Student Member, IEEE, Yu Gong, Gaojie Chen, Member, IEEE
and Jonathon Chambers, Fellow, IEEE
Abstract—Applying data buffers at relay nodes significantly
improves the outage performance in relay networks, but the
performance gain is often at the price of long packet delays.
In this paper, a novel relay selection scheme with significantly
reduced packet delay is proposed. The outage probability and
average packet delay of the proposed scheme under different
channel scenarios are analyzed. Simulation results are also given
to verify the analysis. The analytical and simulation results show
that, compared with non-buffer-aided relay selection schemes,
the proposed scheme has not only significant gain in outage
performance but also similar average packet delay when the
channel SNR is high enough, making it an attractive scheme
in practice.
Index Terms—Relay selection, buffer-aided relay, average delay
I. INTRODUCTION
Relay selection provides an attractive way to harvest the
diversity gain in multiple relay cooperative networks [1], [2].
A typical relay selection system is shown in Fig. 1, which
includes one source node (S), one destination node (D) and
N relay nodes (Rk, 1 ≤ k ≤ N). Analysis shows that full
diversity order can be achieved with the best selected relay
[3]–[5]. In the traditional max-min relay selection scheme,
the best relay is selected with the highest gain among all
of the minima of the source-to-relay and relay-to-destination
channel gain pairs [6]. While the max-min scheme achieves
diversity order of N, its performance is practically limited
by the constraint that the best source-to-relay and relay-to-
destination links for a packet transmission must be determined
concurrently. Recent research has on the other hand found
that introducing data buffers at the relays yields significant
performance advantage in practical systems [7]–[10]. Buffer-
aided relays have also been used in applications including
adaptive link selection [11], [12], cognitive radio networks [13]
and physical layer network security [14].
Copyright (c) 2015 IEEE. Personal use of this material is permitted.
However, permission to use this material for any other purposes must be
obtained from the IEEE by sending a request to pubs-permissions@ieee.org.
This work was supported in part by the Engineering and Physical Sciences
Research Council under Grant EP/K014307/2 and in part by the MOD
University Defence Research Collaboration in Signal Processing.
Gaojie Chen is the corresponding author with the Department of Engineer-
ing Science, University of Oxford, Parks Road, Oxford, UK, OX1 3PJ, Email:
gaojie.chen@eng.ox.ac.uk.
Z. Tian and Y. Gong are with the Advanced Signal Processing
Group, Loughborough University, Loughborough, Leicestershire, UK, Emails:
{z.tian, y.gong}@lboro.ac.uk.
J. A. Chambers is with the Communications, Sensors, Signal and Infor-
mation Processing Group, Newcastle University, Newcastle Upon Tyne, UK,
E-mail: jonathon.chambers@ncl.ac.uk.
Typical buffer-aided relay selection schemes include the
max-max [7] and max-link [8] schemes. In max-max relay
selection, at one time slot t, the best link among all source-
to-relay channels is selected, and a data packet is sent to the
selected relay and stored in the buffer. At the next time slot
(t+1), the best link among all relay-to-destination channels is
selected, and the selected relay (which is often not the same
relay selected at time t) forwards one data packet from its
buffer to the destination. The max-max scheme has significant
coding gain over the traditional max-min scheme. In the max-
link scheme [8], the best link is selected among all available
source-to-relay and relay-to-destination links. Depending on
whether a source-to-relay or a relay-to-destination link is
selected, either the source transmits a packet to the selected
relay or the selected relay forwards a stored packet to the
destination. As a result, the max-link relay selection not only
has coding gain over the max-min scheme, but also higher
diversity order than both the max-min and max-max schemes,
making it more attractive than its max-max counterpart.
The performance gain of either the buffer-aided max-max or
max-link schemes is however at the price of much increased
packet delay. In the non buffer-aided relay selection scheme
(e.g. the max-min scheme), it always takes two time slots
for every packet passing through the network, corresponding
to the source-to-relay and relay-to-destination transmission
respectively. In the buffer aided approach, in contrast, when
a packet is transmitted to a relay node, it is stored in the
buffer and will not be forwarded to the destination until the
corresponding relay-to-destination link is selected. As a result,
different packets in the buffer-aided relay network may endure
different delays. To be specific, in either the max-max or max-
link scheme, the average packet delay increases linearly with
relay number and buffer size. On the other hand, in order to
achieve high performance gain, relay number and buffer size
in the max-max or max-min scheme are often set as high as
possible. This makes the existing buffer-aided relay selection
schemes unsuitable in most applications, particularly in 5G
mobile systems which requires ultra-low latency.
While packet delay reduction has been investigated in
adaptive link selection with infinite buffer size (e.g. [11]),
little has been done for buffer-aided relay selection with finite
buffer size. In this paper, we propose a novel buffer-aided
relay selection scheme with significantly reduced packet delay.
This is achieved by giving higher priority to select the relay-
to-destination than the source-to-relay links, so that the data
queues at relay buffers are as short as possible. The main
contributions of this paper are listed as follows:
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2. This work is licensed under a Creative Commons Attribution 3.0 License. For more information, see http://creativecommons.org/licenses/by/3.0/.
This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Citation information: DOI 10.1109/TVT.2016.2573378, IEEE
Transactions on Vehicular Technology
2
• Proposing a novel relay selection scheme. The proposed
scheme provides a simple yet effective way to reduce the
packet delay in the buffer-aided relay selection.
• Deriving the closed-form expression for outage prob-
ability. The analysis is based on general asymmetric
channel assumption that the source-to-relay and relay-to-
destination links may have different average gains.
• Obtaining the closed-form expression for the average
packet delay. Using Little’s law, the average packet delay
of the proposed scheme is analytically obtained.
• Analyzing the asymptotic performance that the channel
SNR goes to infinity. The asymptotic performances in-
cluding diversity order, coding gain and average packet
delay for infinite channel SNR are analyzed.
The remainder of the paper is organised as follows: Sec-
tion II proposes the new relay selection scheme; Section
III analyzes the outage probability; Section IV analyzes the
average packet delay; Section V analyzes the asymptotic
performance; Section VI shows simulation results; and Section
VII concludes the paper.
II. BUFFER-AIDED RELAY SELECTION WITH REDUCED
DELAY
The system model of buffer-aided relay selection is similar
to that shown in Fig. 1, except that every relay is equipped
with a data buffer Qk (1 ≤ k ≤ N) of finite size L. We assume
relays apply decode-and-forward (DF) protocol. The channel
coefficients for S → Rk and Rk → D links at time slot t are
denoted as hsrk
(t) and hrkd(t) respectively. All channels are
Rayleigh fading, and the average channel gains for S → Rk
and Rk → D links are given by
¯γsr = E[|hsrk
(t)|2
], ¯γrd = E[|hrkd(t)|2
], for all k,
(1)
respectively. We assume without losing generality that all
transmission powers and noise variances are normalized to
unity. We also assume that channel gains in either the source-
to-relay or relay-to-destination links are independent and iden-
tically distributed (i.i.d.), but in general ¯γsr ̸= ¯γrd.
In the existing buffer-aided max-max and max-min relay
selection schemes, the average packet delay increases linearly
with relay number and buffer size. The large delay is due to the
packets queuing at the buffers. This can be seen, for example,
in the max-link scheme with relay number of N and buffer size
of L > 2. Specifically, we assume that all buffers are empty
initially and a packet s1 is sent to relay R1 at time t = 1. Then
at the next time t = 2, except for R1 which contains s1, all
other buffers are still empty. Thus there are (N + 1) available
links for selection in total: N from source-to-relay (S → Rk
for all k) links and one from relay-to-destination (R1 → D)
link. Because the max-link scheme always selects the strongest
link among all available links, the probability that R1 → D is
selected and s1 is forwarded to the destination is 1/(N+1)). In
other words, it is more likely (with probability of N/(N +1))
that s1 remains in R1 at t = 2, leading to one extra time slot
in packet delay. It is clear that this extra delay may be avoided
by forwarding s1 to the destination immediately at t = 2, once
the corresponding R1 → D link is not in outage even though
it is not the strongest link.
Fig. 1. The system model of the relay selection system.
This leads to a new principle of buffer-aided relay selection:
that is to transmit the packets already in the buffers as fast as
possible. This translates into giving higher priority to select the
relay-to-destination links: only when no relay-to-destination
link can be selected, are the source-to-relay links considered.
As a result, the packet queuing lengths at the relay buffers are
minimized, and so is the average packet delay.
To be specific, at time slot t, the link selection rule is as
follows:
1) Choose the link with the highest channel SNR among
all available relay-to-destination links (|hrkd(t)|2
). If the
chosen link is not in outage, the corresponding relay
forwards a packet from its buffer to the destination.
2) Otherwise, if the selected link in step 1) is in outage
or there are no available relay-to-destination links at
time t, choose the link with the highest channel SNR
among all available source-to-relay links (|hsrk
(t)|2
). If
the selected link is not in outage, the source transmits
one packet to the corresponding relay and the packet is
stored in the buffer. Otherwise outage occurs.
The above proposed scheme is easy to implement as it re-
quires the same knowledge as that in the existing buffer-aided
max-max or max-min scheme. In the following 2 sections, the
outage and delay performance of the proposed scheme will be
analyzed respectively.
III. OUTAGE PROBABILITY
The numbers of data packets in all of the relay buffers form
a“state”. With N relays and buffer size of L, there are (L+1)N
states in total. The l-th state vector is defined as
sl = [Ψl(Q1), · · · , Ψl(QK)], l = 1, · · · , (L + 1)N
, (2)
where Ψl(Qk) gives the number of data packets in buffer Qk
at state sl. It is clear that 0 ≤ Ψl(Qk) ≤ L.
Every state corresponds to one pair of (KS→R
sl
, KR→D
sl
),
corresponding to the numbers of available source-to-relay
and relay-to-destination links, respectively. A source-to-relay
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3. This work is licensed under a Creative Commons Attribution 3.0 License. For more information, see http://creativecommons.org/licenses/by/3.0/.
This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Citation information: DOI 10.1109/TVT.2016.2573378, IEEE
Transactions on Vehicular Technology
3
link is considered available when the buffer of the corre-
sponding relay node is not full, and a relay-to-destination
link is available when the corresponding relay buffer is not
empty. At state sl, the total number of available source-to-
relay and relay-to-destination links are denoted as KS→R
sl
and
KR→D
sl
respectively. It is clear that 0 ≤ KS→R
sl
≤ N and
0 ≤ KR→D
sl
≤ N. Specifically, if none of the buffers is full or
empty, all links are available such that KS→R
sl
= KR→D
sl
= N.
Considering all possible states, the outage probability of the
proposed buffer-aided scheme can be obtained as
Pout =
(L+1)N
∑
l=1
πl · psl
out, (3)
where πl is the stationary probability for state sl, and psl
out
is the outage probability at state sl. In the following two
subsections, we derive psl
out and πl respectively.
A. psl
out: outage probability at state sl
For independent Rayleigh fading channels, the instanta-
neous SNR for every channel, γw(w ∈ {srk, rkd}), is inde-
pendently exponentially distributed. In the proposed scheme,
outage occurs if all available source-to-relay links and relay-
to-destination links are in outage. Thus the outage probability
at state sl is given by
psl
out = pS→R
out · pR→D
out (4)
where
pS→R
out =
(
1 − e− ∆
¯γsr
)KS→R
sl
,
pR→D
out =
(
1 − e
− ∆
¯γrd
)KR→D
sl
(5)
where pS→R
out and pR→D
out are probabilities that all available
source-to-relay links and relay-to-destination links are in out-
age respectively, rt is the target data rate and ∆ = 2rt
− 1.
B. πl: stationary probability of the state sl
We denote A as the (L + 1)N
× (L + 1)N
state transition
matrix, where the entry An,l = P(Xt+1 = sn|Xt = sl) is the
transition probability that the state moves from sl at time t to
sn at time (t + 1).
We assume that at time slot t the state is at sl. The
probability to select one relay-to-destination link is when not
all of the available relay-to-destination links are in outage, or
pR→D
sl
=
1
KR→D
sl
·
(
1 − pR→D
out
)
=
1
KR→D
sl
·
(
1 −
(
1 − e
− ∆
¯γrd
)KR→D
sl
)
.
(6)
On the other hand, because a source-to-relay link is selected
only when all relay-to-destination links are in outage and not
all source-to-relay links are in outage, the probability to select
one source-to-relay link at state sl is given by
pS→R
sl
=
1
KS→R
sl
· pR→D
out ·
(
1 − pS→R
out
)
=
1
KS→R
sl
·
(
1 − e
− ∆
¯γrd
)KR→D
sl
·
(
1 −
(
1 − e− ∆
¯γsr
)KS→R
sl
)
.
(7)
With these observations, the (n, l)-th entry of the state
transition matrix A is expressed as
An,l =
psl
out, if sn = sl,
pR→D
sl
if sn ∈ UR→D
sl
,
pS→R
sl
, if sn ∈ US→R
sl
,
0, elsewhere,
(8)
where psl
out, pR→D
sl
and pS→R
sl
are given by (4), (6) and (7)
respectively, UR→D
sl
and US→R
sl
are the sets containing all
states to which sl can move when a relay-to-destination link
or a source-to-relay link is selected respectively.
Because the transition matrix A in (8) is column stochastic,
irreducible and aperiodic1
, the stationary state probability
vector is obtained as (see [15])
π = (A − I + B)−1
b, (9)
where π = [π1, · · · , π(L+1)N ]T
, b = (1, 1, ..., 1)T
, I is the
identity matrix and Bn,l is an n × l all one matrix.
Finally, substituting (8) and (9) into (3) gives the outage
probability as
Pout =
(L+1)N
∑
l=1
πl · psl
out = diag(A) · π
= diag(A) · (A − I + B)−1
b,
(10)
where diag(A) is a vector consisting of all diagonal elements
of A.
IV. AVERAGE PACKET DELAY
The delay of a packet in the system is the duration between
the time when the packet leaves the source node and the time
when it arrives the destination. Because it takes one time slot to
transmit a packet from the source to a relay node, the average
packet delay in the system is given by
¯D = 1 + ¯Dr, (11)
where ¯Dr is the average delay at the relay nodes.
Because the average delay through every relay node is the
same, only the average delay through relay Rk is analyzed
below. Based on Little’s Law [16], the average packet delay
at relay Rk is given by
¯Dr = ¯Dk =
¯Lk
¯ηk
, (12)
where ¯Lk and ¯ηl are the average queuing length and average
throughput at Rk respectively.
1Column stochastic means all entries in any column sum up to one,
irreducible means that it is possible to move from any state to any state,
and aperiodic means that it is possible to return to the same state at any steps
[15].
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The average queuing length at Rk is obtained by averaging
the queueing lengths at buffer Qk over all states, or
¯Lk =
(L+1)N
∑
l=1
πlΨl(Qk) (13)
where Ψl(Qk) gives the number of packets (or the buffer
length) of buffer Qk at state sl, and πl is given by (9).
On the other hand, because the probabilities to select any
of the relays are the same, the average throughput at relay Rk
is given by
¯ηk =
¯η
N
(14)
where ¯η is the average throughput of the overall system net-
work. For delay-limited transmission, the average throughput
¯η is obtained as (see [17], [18])
¯η = R · (1 − Pout), (15)
where R is the average data rate of the system (without con-
sidering the outage probability). In the proposed scheme, every
packet requires two time slots (not necessarily consecutively)
to reach the destination, we have R = 1/2 and thus
¯ηk =
1 − Pout
2N
. (16)
Substituting (13) and (16) into (12), and further into (11), gives
¯D = 1 +
2 · N ·
∑(L+1)N
l=1 πlΨl(Qk)
1 − Pout
. (17)
V. ASYMPTOTIC PERFORMANCE
This section analyzes the asymptotic performance of the
proposed scheme when the average channel SNR goes to
infinity. The average channel SNRs for source-to-relay and
relay-to-destination link can be respectively expressed as
¯γsr = α¯γ and ¯γrd = β¯γ, (18)
where α and β are positive real constants, and ¯γ is the
normalized average channel SNR. Below we first derive the
asymptotic outage probability for ¯γ → ∞, from which the
diversity order, coding gain and average packet delay are
obtained.
A. Asymptotic outage probability
When ¯γ → ∞, it is clear from (6) that
lim
¯γ→∞
pR→D
sl
= 1, if KR→D
sl
̸= 0. (19)
This implies that, any packets in the relay buffers will be
forwarded to the destination, and only after all buffers are
empty, is a new packet transmitted to one of the relays. Thus
when ¯γ → ∞, the buffers can only be in two possible states:
S(0)
and S(1)
, corresponding to the cases that all buffers are
empty and only one of the buffers has on packet, respectively.
It is then from (3) that
lim
¯γ→∞
Pout = P(S(0)
) · pS(0)
out + P(S(1)
) · pS(1)
out , (20)
where P(S(0)
) and P(S(1)
) are the probabilities that buffers
are in states S(0)
and S(1)
respectively, and pS(0)
out and pS(1)
out
are the corresponding outage probabilities.
Suppose at time t all buffers are empty so that the state is
in S(0)
. Then one packet will be transmitted to a relay at time
(t + 1), and the state moves to S(1)
. From (19), the packet
in the buffer must be forwarded to the destination at (t + 2)
and the state returns to S(0)
. This process continues until all
packets are transmitted. Thus we have
P(S(0)
) = P(S(1)
) =
1
2
(21)
When the buffers are in state S(0)
, there are N avail-
able source-to-relay links and no available relay-to-destination
links, or we have
pS(0)
out =
(
1 − e− ∆
¯γsr
)N
. (22)
When the buffers are in state S(1)
, there is one available relay-
to-destination link. And the number of available source-to-
relay links is denoted as K∞, where K∞ = N − 1 or N, for
buffer size L = 1 or larger respectively. Then we have
pS(1)
out =
(
1 − e− ∆
¯γsr
)K∞
·
(
1 − e
− ∆
¯γrd
)
. (23)
Substituting (21), (22) and (23) into (20) gives
lim
¯γ→∞
Pout =
1
2
·
(
1 − e− ∆
α¯γ
)N
+
1
2
·
(
1 − e− ∆
α¯γ
)K∞
×
(
1 − e− ∆
β¯γ
)
.
(24)
B. Diversity order
The diversity order can be defined as
d = − lim
¯γ→∞
log Pout
log ¯γ
. (25)
If the buffer size L = 1, substituting (24) into (25), and
further noting that ex
≈ 1 + x for very small x, we have the
diversity order for L = 1 as
d(L=1)
= − lim
¯γ→∞
log
[
1
2 ·
(
∆
α¯γ
)N−1
·
(
∆
α¯γ + ∆
β¯γ
)]
log ¯γ
= N
(26)
If the buffer size L ≥ 2, from (24), the asymptotic outage
probability is given by
lim
¯γ→∞
P
(L≥2)
out = lim
¯γ→∞
[
1
2
·
(
∆
α¯γ
)N
·
(
β¯γ + ∆
β¯γ
)]
. (27)
Because
lim
¯γ→∞
(β¯γ) < lim
¯γ→∞
(β¯γ + ∆) < lim
¯γ→∞
(2 · β¯γ) , (28)
the diversity order for L ≥ 2 can be obtained
N < d(L≥2)
< N + 1 (29)
C. Coding gain
The coding gain is defined as the SNR difference (in dB)
between the traditional max-min and proposed schemes to
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achieve the same outage probability, or
C(dB) = −
lim¯γ→∞ ∆P (¯γ)
d
, (30)
where d = N which is the diversity order, and
∆P (¯γ) = 10 log P
(max−min)
out (¯γ) − 10 log P
(L=1)
out (¯γ), (31)
where P
(max−min)
out (¯γ) and P
(L=1)
out (¯γ) are the outage probabil-
ities at ¯γ for the max-min and proposed schemes respectively.
For fair comparison, the buffer size is set as L = 1 so that the
diversity order for the max-min and proposed schemes are the
same as d = N.
From (24), we have
lim
¯γ→∞
10 log P
(L=1)
out =10 · log
[
1
2
·
(
1
α
)N−1 (
1
α
+
1
β
)]
+ lim
¯γ→∞
10 · log
(
∆
¯γ
)N
(32)
For the tradition max-min scheme, we have
lim
¯γ→∞
10 log P
(max-min)
out = lim
¯γ→∞
10 · log
(
∆
α¯γ
+
∆
β¯γ
)N
= 10 · log
(
1
α
+
1
β
)N
+ lim
¯γ→∞
10 · log
(
∆
¯γ
)N
(33)
Substituting (32) and (33) into (31) gives
lim
¯γ→∞
∆P (¯γ) = −10 · log
[
1
2
(
β
α + β
)N−1
]
. (34)
Finally, substituting (34) into (30) gives the coding gain of
the proposed scheme as
C(dB) =
−10 · log
[
1
2
(
β
α+β
)N−1
]
N
(35)
It is interesting to observe that, for symmetric channel config-
uration with α = β, the coding gain is 3dB.
D. Average packet delay
We have shown that, when ¯γ → ∞, the buffer states can
only be in either S(0)
or S(1)
, or a buffer can only be empty or
contains one packet. When all buffers are empty, a new packet
is transmitted to a relay with probability of 1/N. Further from
(21) that P(S(1)
) = 1/2, the probability that Qk contains one
packet is given by
P(Qk = 1) = P(S(1)
) ·
1
N
=
1
2N
. (36)
Thus, when ¯γ → ∞, the average buffer length at relay Rk is
given by
lim
¯γ→∞
¯Lk = 1 · P(Qk = 1) = P(S(1)
) ·
1
N
=
1
2N
. (37)
From (16), and noticing that lim¯γ→∞ Pout = 0, the average
throughput at relay Qk is given by
lim
¯γ→∞
ηk =
lim¯γ→∞(1 − Pout)
2N
=
1
2N
(38)
Finally, substituting (37) and (38) into (12), and further into
(11), gives the average packet delay for ¯γ → ∞ as
lim
¯γ→∞
¯D = 1 +
1/(2N)
1/(2N)
= 2. (39)
It is clearly shown in (39) that, when SNR is high enough,
the average packet delay of the proposed scheme is the same
as that for the non-buffer-aided schemes.
E. Comparison between different schemes in symmetric chan-
nel configuration
For the symmetric channel configuration, Table I compares
the diversity order, coding gain and average delay for the non-
buffer-aided max-min, traditional buffer-aided max-max and
max-link, and the proposed schemes.
TABLE I
ASYMPTOTIC PERFORMANCE COMPARISON AMONG DIFFERENT SCHEMES
FOR SYMMETRIC CHANNELS
max-min max-max max-link proposed
diversity order N N [N, 2N) (N, N + 1)
coding gain 0 dB 3 dB 3 dB 3 dB
average delay 2 NL
2
+ 1 NL + 1 2
Table I shows that all buffer-aided schemes have 3dB coding
gain over the max-min scheme. While the proposed link has
slightly higher diversity order than the max-max scheme, but
lower diversity order than the max-link scheme. In either
the max-max or max-link scheme, the average packet delay
increases linearly with relay number N and buffer size L. In
the proposed scheme, when ¯γ → ∞, the average delay is
fixed at 2 which is the same as that for the non buffer-aided
max-min scheme.
For asymmetric channels, the comparison between schemes
is not as same as that shown in Table I and will be discussed
in the following section.
VI. SIMULATIONS AND DISCUSSIONS
This section verifies the proposed scheme with numerical
simulations, where the results for previous described max-link
and non-buffer-aided max-min schemes are also shown for
comparison. In the simulation below, the transmission rates in
all schemes are set as rt = 2 bps/Hz, and simulation results
are obtained with 1, 000, 000 Monte Carlo runs. Particularly
in the proposed scheme, the simulation results always well
match the theoretical analysis.
A. Symmetric channel configuration: ¯γsr = ¯γrd
In the first simulation, we consider symmetric channel
scenario that the source-to-relay and relay-to-destination links
have same average channel SNR-s.
Fig. 2 (a) and (b) compare the outage probabilities and av-
erage packet delays for the non-buffered max-min, traditional
max-link and proposed schemes respectively, where the relay
number is fixed at N = 3, and we let α = β = 1.5 and ¯γ = 10
dB in (18) so that ¯γsr = ¯γrd = 15 dB. Fig. 2 (a) shows that,
when the buffer size L = 1, the proposed and max-link have
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0 2 4 6 8 10 12 14 16 18 20
10
−7
10
−6
10
−5
10
−4
10
−3
10
−2
10
−1
10
0
¯γ [dB]
outageprobability
max−min
proposed with L=1 (Simulation)
proposed with L=1 (Theory)
max−link with L=1
proposed with L=5 (Simulation)
proposed with L=5 (Theory)
max−link with L=5
(a) Outage probability
0 2 4 6 8 10 12 14 16 18 20
0
10
20
30
40
50
60
70
¯γ [dB]
averagepacketdelay
max−link with L=5
proposed with L=5 (Simulation)
proposed with L=5 (Theory)
max−link with L=1
proposed with L=1 (Simulation)
proposed with L=1 (Theory)
17.5 18 18.5
1
2
3
4
5
(b) Average delay
Fig. 2. Outage probabilities and average delay among different schemes, where ¯γsr = ¯γrd = 10 dB.
2 4 6 8 10 12 14 16 18 20
0
5
10
15
20
25
30
35
40
45
AverageDelay
Buffer Size L
max−link scheme
proposed scheme
(a) Delay vs buffer size, where N = 2
1 2 3 4 5 6 7 8 9 10
0
20
40
60
80
100
120
AverageDelay
Relay Number N
max−link scheme
proposed scheme
(b) Delay vs relay number, where L = 10
Fig. 3. Average packet delay comparison between the max-link and proposed schemes
70 72 74 76 78 80 82 84 86 88 90
10
−38
10
−36
10
−34
10
−32
10
−30
10
−28
10
−26
S−R channel SNR [dB]
outageprobability
N=4 max−min scheme
N=4 L=1 proposed scheme
N=4 L=8 proposed scheme
x1
≈−315dB
x2
≈−340dB
Fig. 4. Diversity order and Coding gain of the proposed scheme.
the same outage probabilities, where both have significantly
better outage performance than the traditional non-buffer-aided
max-min scheme because of the 3dB coding gain. When the
buffer size increases to L = 5, the proposed scheme has
slightly better outage performance than that for L = 1. This
well matches the asymptotic analysis that, when L ≥ 2, the
diversity order is larger than N but smaller than (N + 1) for
the proposed scheme. On the other hand, for the max-link
scheme, the outage performance improves more significantly
with larger buffer size. This is because that diversity order
of the max-link scheme goes up with the buffer size, until
it reaches 2N when L → ∞. Fig. 2 (b) shows that, even
for L = 1, the average delay of the max-link scheme is at
least twice as much that for the proposed scheme. When the
buffer size increases to L = 5, the average packet delay of the
proposed scheme still maintains at 2 in high SNR range, which
is the same as that for L = 1. On the other hand, when L = 5,
the average packet delay of the max-link scheme increases to
18 at high SNR-s, which is 9 times larger than that of the
proposed scheme.
To further compare the delay performance of the max-link
and proposed schemes in symmetric channels, Fig. 3 (a) and
(b) show the average packet delay vs the buffer size and relay
number respectively, where the average channel SNR-s in both
schemes are set as 10 dB. In Fig. 3 (a), the relay number is
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0 2 4 6 8 10 12
10
−7
10
−6
10
−5
10
−4
10
−3
10
−2
10
−1
10
0
¯γ [dB]
outageprobability
max−min
max−link with L=1
max−link with L=5
proposed with L=1 (Theory)
proposed with L=1 (Simulation)
proposed with L=5 (Theory)
proposed with L=5 (Simulation)
(a) Outage probability
0 5 10 15 20 25 30 35 40
0
10
20
30
40
50
60
70
¯γ [dB]
averagepacketdelay
max−link with L=5
proposed with L=5 (Simulation)
proposed with L=5 (Theory)
max−link with L=1
proposed with L=1 (Simulation)
proposed with L=1 (Theory)
34 36 38
2
4
6
8
(b) Average delay
Fig. 5. Outage probabilities and average delay among different schemes, where ¯γsr = 20 dB and ¯γrd = 10 dB.
0 2 4 6 8 10 12 14 16 18 20
10
−6
10
−5
10
−4
10
−3
10
−2
10
−1
10
0
¯γ [dB]
outageprobability
max−min
proposed with L=1 (Simulation)
proposed with L=1 (Theory)
proposed with L=5 (Simulation)
proposed with L=5 (Theory)
max−link with L=1
max−link with L=5
(a) Outage probability
0 2 4 6 8 10 12 14 16 18 20
0
10
20
30
40
50
60
70
¯γ [dB]
averagepacketdelay
max−link with L=5
proposed with L=5 (Simulation)
proposed with L=5 (Theory)
max−link with L=1
proposed with L=1 (Simulation)
proposed with L=1 (Theory)
15.8 16 16.2
1.5
2
2.5
(b) Average delay
Fig. 6. Outage probabilities and average delay among different schemes, where ¯γsr = 10 dB and ¯γrd = 20 dB.
fixed at N = 2, and the buffer size varies from 1 to 20. In
Fig. 3 (b), the buffer size is fixed at L = 10, but the relay
number varies from 1 to 10. It is clearly shown in both Fig.
3 (a) and (b) that, the average packet delay for the proposed
scheme remains at a constant value of 2. On the other hand,
the packet delay in the max-link scheme goes up linearly with
either N or L.
In order to reveal the diversity order and coding gain of the
proposed scheme, Fig. 4 compares the outage probabilities of
the proposed and non-buffer-aided max-min scheme at very
high SNR-s, where the relay number is set as N = 4 and all
results are from theoretical analysis. First the coding gain is
clearly 3 dB by comparing the max-min and proposed scheme
with L = 1. For example, to achieve the outage probability of
10−34
, the SNR-s for the max-min and proposed scheme with
L = 1 are about 85 and 88dB respectively. The diversity order
of the proposed scheme is also clearly shown to be (N, N +1)
for L ≥ 2. For example, as is illustrated in the figure, for the
proposes scheme with L = 8, the SNRs to achieve the outage
probabilities of −315 and −340 dB are about 78 and 84 dB,
respectively. Then according to the diversity order definition in
(25), the diversity order is obtained as (340−315)/(84−78) =
4.17, which is clearly between N = 4 and N + 1 = 5.
B. Asymmetric channel configuration: ¯γsr > ¯γrd
In Fig. 5, we consider asymmetric channels that source-
to-relay links are stronger than relay-to-destination links in
average, where we let α = 2, β = 1 and ¯γ = 10 dB in (18)
so that ¯γsr = 20 dB and ¯γrd = 10 dB, and relay number is
fixed at N = 3.
It is very interesting to observe in Fig. 5 (a) that, for both
L = 1 and L = 5, the outage performance of the proposed
scheme is significantly better than the max-link scheme! This
is because that, when the source-to-relay links are stronger
than relay-to-destination links, the max-link scheme is more
likely to select the source-to-relay links so that the buffers
are more likely full. This effectively decreases the number of
the available source-to-relay links, leading to fewer diversity
order. On the other hand, in the proposed scheme, while the
channel condition gives higher priority to the source-to-relay
selection, the selection rule gives higher priority to the relay-
to-destination link selection. This leads to a more ‘balanced’
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buffers at the relays, or fewer full or empty buffers, which
again increases the diversity order.
Fig. 5 (b) shows that, the average delay of the max-link
even worse than that in symmetric channels. This is because
the buffers are more likely to be full, or higher queuing length
at buffers. On the contrary, the average delay for the proposed
scheme is still as low as about 2 at high SNR range.
Therefore, when ¯γsr > ¯γrd, the proposed scheme has better
performance in both outage probability and average delay than
the max-link scheme.
C. Asymmetric channel configuration: ¯γsr < ¯γrd
Fig. 6 assumes that the source-to-relay link is weaker than
the relay-to-destination link in average, where we let α = 1,
β = 2 and and ¯γ = 10 dB in (18) so that ¯γsr = 10 dB and
¯γrd = 20 dB, and relay number is set as N = 3.
It is interesting to observe in Fig. 6 that, the max-link and
proposed schemes have similarly performance both in outage
and average delay. This is because that, stronger relay-to-
destination links ‘naturally’ give higher priority to select the
relay-to-destination links. But even under this channel assump-
tion, the average packet delay is still better constrained in the
proposed scheme than in the max-link scheme, particularly in
low SNR ranges.
VII. CONCLUSION
This paper proposed a novel buffer-aided relay selection
scheme with significantly reduced packet delays. We have
shown the outage and average delay performance under dif-
ferent channel configurations. To be specific, for symmetric
S → R and R → D channels, the max-link scheme has better
outage performance than the proposed. But when S → R
links are stronger, the proposed scheme performs better in
outage than the max-link. On the other hand, when R → D
links are stronger, the max-link and proposed scheme have
similar outage performance. Therefore, if the relay nodes are
evenly spread within an area as in many practical systems,
it is reasonable to expect that the outage performance of
the proposed and max-link schemes are similar. This will be
left for future study. We also highlight that, in all cases, the
proposed scheme has significantly better outage performance
than the non-buffer-aided schemes, making it an attractive
scheme in practical applications.
ACKNOWLEDGEMENT
The authors wish to thank associate editor and anonymous
reviewers for significantly improving out the manuscript, par-
ticularly one of the reviewers for pointing out the parallel
work in the Master’s dissertation [19], in which Algorithms
2 and 3 were proposed with similar ideas to that in this paper.
Algorithm 2 (which is based on giving higher priority to relays
with longer queuing length) has similar performance to our
proposed scheme, but it is more complicated to implement.
Algorithm 3 trades off between outage and delay performance,
and in some cases may have longer delay than the ‘standard’
buffer-aided max-link scheme. Our work was done indepen-
dently from the work in the Master’s dissertation.
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KTH Master dissertation available at “http://kth.diva-
portal.org/smash/record.jsf?pid=diva2%3A813435&dswid=5372”,
2015.
Zhao Tian (S’12-M’15) received the B. Eng and
Ph.D degrees in School of Electronic, Electrical and
Systems Engineering from Loughborough Univer-
sity, UK, in 2012 and 2015, respectively. He received
full postgraduate scholarship from Engineering and
Physical Sciences Research Council (EPSRC) when
he was working toward the Ph.D degree. He is
currently a Knowledge Transfer Project Associate in
Computer Science of Aston University, Birmingham
and IGI Ltd., Birmingham. His current research
interests include the general field of wireless com-
munications with emphasis on buffer-aided relaying, machine learning and
data mining.
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9. This work is licensed under a Creative Commons Attribution 3.0 License. For more information, see http://creativecommons.org/licenses/by/3.0/.
This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Citation information: DOI 10.1109/TVT.2016.2573378, IEEE
Transactions on Vehicular Technology
9
Yu Gong is with School of Electronic, Electrical
and Systems Engineering, Loughborough University,
UK, in July 2012. Dr Gong obtained his BEng and
MEng in electronic engineering in 1992 and 1995
respectively, both at the University of Electronics
and Science Technology of China. In 2002, he re-
ceived his PhD in communications from the National
University of Singapore. After PhD graduation, he
took several research positions in Institute of Infor-
comm Research in Singapore and Queens University
of Belfast in the UK respectively. From 2006 and
2012, Dr Gong had been an academic member in the School of Systems
Engineering, University of Reading, UK. His research interests are in the area
of signal processing and communications including wireless communications,
cooperative networks, non-linear and non-stationary system identification and
adaptive filters.
Gaojie Chen (S’09-M’12) received the B. Eng. and
B. Ec. in Electrical Information Engineering and
International Economics and Trade from the North-
west University, Shaanxi, China, in 2006, and the
M.Sc (Distinction) and Ph.D degrees from Lough-
borough University, Loughborough, UK, in 2008 and
2012, respectively, all in Electrical and Electronic
Engineering. From 2008 to 2009 he worked, as a
software engineering in DTmobile, Beijing, China,
and from 2012 to 2013 as a Research Associate
in the School of Electronic, Electrical and Systems
Engineering at the Loughborough University, Loughborough, UK. Then he
was a Research Fellow with the 5GIC, the Faculty of Engineering and Physical
Sciences, University of Surrey, U.K., from 2014 to 2015. He is currently a
Research Associate with the Department of Engineering Science, University of
Oxford, U.K. His current research interests include information theory, wire-
less communications, cooperative communications, cognitive radio, secrecy
communication and random geometric networks.
Jonathon A. Chambers (S’83-M’90-SM’98-F’11)
received the Ph.D. and D.Sc. degrees in signal
processing from the Imperial College of Science,
Technology and Medicine (Imperial College Lon-
don), London, U.K., in 1990 and 2014, respectively.
From 1991 to 1994, he was a Research Scientist
with the Schlumberger Cambridge Research Centre,
Cambridge, U.K. In 1994, he returned to Imperial
College London as a Lecturer in signal processing
and was promoted to Reader (Associate Professor)
in 1998. From 2001 to 2004, he was the Director of
the Centre for Digital Signal Processing and a Professor of signal processing
with the Division of Engineering, Kings College London. From 2004 to 2007,
he was a Cardiff Professorial Research Fellow with the School of Engineering,
Cardiff University, Cardiff, U.K. Between 2007-2014, he led the Advanced
Signal Processing Group, within the School of Electronic, Electrical and
Systems Engineering and is now a Visiting Professor. In 2015, he joined
the School of Electrical and Electronic Engineering, Newcastle University,
where he is a Professor of signal and information processing and heads
the ComS2IP group. He is also a Guest Professor at Harbin Engineering
University, China. He is a co-author of the books Recurrent Neural Networks
for Prediction: Learning Algorithms, Architectures and Stability (New York,
NY, USA: Wiley, 2001) and EEG Signal Processing (New York, NY, USA:
Wiley, 2007). He has advised more than 60 researchers through to Ph.D.
graduation and published more than 400 conference proceedings and journal
articles, many of which are in IEEE journals. His research interests include
adaptive and blind signal processing and their applications.
Dr. Chambers is a Fellow of the Royal Academy of Engineering, U.K., and
the Institution of Electrical Engineers. He was the Technical Program Chair
of the 15th International Conference on Digital Signal Processing and the
2009 IEEE Workshop on Statistical Signal Processing, both held in Cardiff,
U.K., and a Technical Program Co-chair for the 36th IEEE International
Conference on Acoustics, Speech, and Signal Processing, Prague, Czech
Republic. He received the first QinetiQ Visiting Fellowship in 2007 for his
outstanding contributions to adaptive signal processing and his contributions
to QinetiQ, as a result of his successful industrial collaboration with the
international defence systems company QinetiQ. He has served on the IEEE
Signal Processing Theory and Methods Technical Committee for six years
and the IEEE Signal Processing Society Awards Board for three years. He is
currently a member of the IEEE Signal Processing Conference Board and the
European Signal Processing Society Best Paper Awards Selection Panel. He
has also served as an Associate Editor for the IEEE TRANSACTIONS ON
SIGNAL PROCESSING for three terms over the periods 1997-1999, 2004-
2007, and since 2011 as a Senior Area Editor.
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