Wireless sensor networks （WSNs） consist of sensor nodes that broadcast a message within a network. Efficient broadcasting is a key requirement in sensor networks and has been a focal point of research over the last ...Wireless sensor networks （WSNs） consist of sensor nodes that broadcast a message within a network. Efficient broadcasting is a key requirement in sensor networks and has been a focal point of research over the last few years. There are many challenging tasks in the network, including redundancy control and sensor node localization that mainly depend on broadcasting. In this paper, we propose a broadcasting algorithm to control redundancy and improve localization （BACRIL） in WSNs. The proposed algorithm incorporates the benefits of the gossip protocol for optimizing message broadcasting within the network. Simulation results show a controlled level of redundancy, which is up to 57.6% if the number of sensor nodes deployed in a 500 m×500 m area are increased from 50 to 500.展开更多
Broadcasting is an important operation and been widely used in wireless sensor networks （WSNs）. These networks are power constrained as nodes operate with limited battery power. Wireless sensor networks are spatial ...Broadcasting is an important operation and been widely used in wireless sensor networks （WSNs）. These networks are power constrained as nodes operate with limited battery power. Wireless sensor networks are spatial graphs that have much more clustered and much high path-length characteristics. After considering energy- efficient broadcasting in such networks, by combining the small-world characteristic of WSNs and the properties of ant algorithm to quickly identify an optimal path, small-world power-aware broadcast algorithm is introduced and evaluated. Given different densities of network, simulation results show that our algorithm significantly improves life of networks and also reduces communication distances and power consumption.展开更多
Broadcasting is a fundamental operation in any wireless networks, more so in wireless ad hoc sensor networks, where each sensor node has limited transmission range as well as battery power. Although broadcasting in wi...Broadcasting is a fundamental operation in any wireless networks, more so in wireless ad hoc sensor networks, where each sensor node has limited transmission range as well as battery power. Although broadcasting in wireless ad hoc sensor networks has many advantages but it can cause serious problems like-broadcast storm, which could cause a lot of contention, redundant retransmission, collision and most importantly, drain immense amount of energy from limited battery powered sensor nodes. In this work, our objective is to reduce the number of retransmission and energy consumption of sensor nodes by using the duty cycle property of wireless ad hoc sensor networks. We propose a preamble-based broadcasting technique for wireless ad hoc sensor networks. We show that in dense wireless ad hoc sensor networks a small size preamble can give maximum network-wide data dissemination rather than using the large preamble, which will only consume immense amount of energy during packet reception.展开更多
Due to the mutual interference and sharing of wireless links in TDMA wireless sensor networks, conflicts will occur when data messages are transmitting between nodes. The broadcast scheduling problem （BSP） is aimed ...Due to the mutual interference and sharing of wireless links in TDMA wireless sensor networks, conflicts will occur when data messages are transmitting between nodes. The broadcast scheduling problem （BSP） is aimed to schedule each node in different slot of fixed length frame at least once, and the objective of BSP is to seek for the optimal feasible solution, which has the shortest length of frame slots, as well as the maximum node transmission. A two-stage mixed algorithm based on a fuzzy Hopfield neural network is proposed to solve this BSP in wireless sensor network. In the first stage, a modified sequential vertex coloring algorithm is adopted to obtain a minimal TDMA frame length. In the second stage, the fuzzy Hopfleld network is utilized to maximize the channel utilization ratio. Experimental results, obtained from the running on three benchmark graphs, show that the algorithm can achieve better performance with shorter frame length and higher channel utilizing ratio than other exiting BSP solutions.展开更多
Recently, network coding has been applied to the loss recovery of reliable broadcast transmission in wireless networks. Since it was proved that fi nding the optimal set of lost packets for XOR-ing is a complex NP-com...Recently, network coding has been applied to the loss recovery of reliable broadcast transmission in wireless networks. Since it was proved that fi nding the optimal set of lost packets for XOR-ing is a complex NP-complete problem, the available time-based retransmission scheme and its enhanced retransmission scheme have exponential computational complexity and thus are not scalable to large networks. In this paper, we present an efficient heuristic scheme based on hypergraph coloring and also its enhanced heuristic scheme to improve the transmission efficiency. Basically, our proposed schemes fi rst create a hypergraph according to the packet-loss matrix. Then our schemes solve the problem of generating XORed packets by coloring the edges of hypergraph. Extensive simulation results demonstrate that, the heuristic scheme based on hypergraph coloring and its enhanced scheme can achieve almost the same transmission efficiency as the available ones, but have much lower computational complexity, which is very important for the wireless devices without high computation capacity.展开更多
In this paper, we present a detailed analytical study of previously proposed variable preamble length-based broadcasting scheme for wireless sensor networks (WSNs). Analytical results show that in dense wireless senso...In this paper, we present a detailed analytical study of previously proposed variable preamble length-based broadcasting scheme for wireless sensor networks (WSNs). Analytical results show that in dense wireless sensor networks, broadcasting a packet with a small size preamble can significantly improve the energy conservation on already limited battery powered sensor nodes. For fairer comparison with variable preamble length-based broadcasting scheme, a comprehensive analytical study for an existing probability-based broadcasting scheme is also presented. Analytically calculated results show that variable preamble length-based broadcasting scheme is more energy-efficient than the probability-based broadcasting scheme.展开更多
Deep learning-based Joint Source-Channel Coding(JSCC)is a crucial component in semantic communication,and recent research has made significant progress in adapting to different channels.In this paper,we propose a mult...Deep learning-based Joint Source-Channel Coding(JSCC)is a crucial component in semantic communication,and recent research has made significant progress in adapting to different channels.In this paper,we propose a multi-stage progressive technique called Deep learning based Progressive Joint Source-Channel Coding(DP-JSCC).This approach partitions the source into multiple stages and transmits the signals continuously.The receiver gradually enhances the quality of image reconstruction by progressively receiving the signals,offering greater flexibility compared to existing dynamic rate transmission methods.The model adopts a lightweight architectural design,where we introduce an efficient module called the Inverted Shuffle Attention Bottleneck(ISAB)and incorporate self-attention mechanisms in the encoding and decoding process to capture signal correlations and establish long-range dependencies.Additionally,we introduce the Progressive Focus Weight Allocation(PFWA)method to improve the image reconstruction capability in progressive transmission tasks.These design enhance the expressive capacity of the model.Simulation results demonstrate that DP-JSCC can flexibly adjust the transmission rate according to requirements without the need for retraining or deployment,enabling continuous optimization of signals at different rates.Furthermore,compared to stateof-the-art JSCC methods,DP-JSCC exhibits advantages in terms of computational complexity,parameter count,and reconstruction performance.展开更多
1.Introduction It has been almost 60 years since the launch of Intelsat-I,the world’s first commercial satellite communications system.Over the past few decades,the development of satellite communications has been dr...1.Introduction It has been almost 60 years since the launch of Intelsat-I,the world’s first commercial satellite communications system.Over the past few decades,the development of satellite communications has been driven by both technological advancements and growing application demands,which have given rise to three primary services:broadcast,fixed satellite,and mobile satellite services[1].展开更多
In traditional wireless broadcast networks,a corrupted packet must be retransmitted even if it has been lost by only one receiver.Obviously,this is not bandwidth-efficient for the receivers that already hold the retra...In traditional wireless broadcast networks,a corrupted packet must be retransmitted even if it has been lost by only one receiver.Obviously,this is not bandwidth-efficient for the receivers that already hold the retransmitted packet.Therefore,it is important to develop a method to realise efficient broadcast transmission.Network coding is a promising technique in this scenario.However,none of the proposed schemes achieves both high transmission efficiency and low computational complexity simultaneously so far.To address this problem,a novel Efficient Opportunistic Network Coding Retransmission(EONCR)scheme is proposed in this paper.This scheme employs a new packet scheduling algorithm which uses a Packet Distribution Matrix(PDM)directly to select the coded packets.The analysis and simulation results indicate that transmission efficiency of EONCR is over 0.1,more than the schemes proposed previously in some simulation conditions,and the computational overhead is reduced substantially.Hence,it has great application prospects in wireless broadcast networks,especially energyand bandwidth-limited systems such as satellite broadcast systems and Planetary Networks(PNs).展开更多
Fast data synchronization in wireless ad hoc networks is a challenging and critical problem.It is fundamental for efficient information fusion,control and decision in distributed systems.Previously,distributed data sy...Fast data synchronization in wireless ad hoc networks is a challenging and critical problem.It is fundamental for efficient information fusion,control and decision in distributed systems.Previously,distributed data synchronization was mainly studied in the latency-tolerant distributed databases,or assuming the general model of wireless ad hoc networks.In this paper,we propose a pair of linear network coding(NC)and all-to-all broadcast based fast data synchronization algorithms for wireless ad hoc networks whose topology is under operator’s control.We consider both data block selection and transmitting node selection for exploiting the benefits of NC.Instead of using the store-and-forward protocol as in the conventional uncoded approach,a compute-and-forward protocol is used in our scheme,which improves the transmission efficiency.The performance of the proposed algorithms is studied under different values of network size,network connection degree,and per-hop packet error rate.Simulation results demonstrate that our algorithms significantly reduce the times slots used for data synchronization compared with the baseline that does not use NC.展开更多
Directed diffusion is a data dissemination protocol for wireless sensor networks. In directed diffusion, flooding is used for dissemination of interest and exploratory data, which will bring broadcast storm resulting ...Directed diffusion is a data dissemination protocol for wireless sensor networks. In directed diffusion, flooding is used for dissemination of interest and exploratory data, which will bring broadcast storm resulting in substantial energy consumption of networks. A grid-based directed diffusion is presented to improve the energy efficiency of directed diffusion. Virtual geographic grid clusters are constructed by self-organization of nodes using geographic location information. The flooding of interest and exploratory data of original directed diffusion is limited in cluster head nodes. The simulation results and testbed experiments show that the method effectively reduces the network energy consumption. This gain is not achieved at the cost of either delivery ratio or the delay. Importantly, the decreased load also leads to a better delivery ratio and lower delay.展开更多
Over the past years, we have witnessed an explosive growth in the use of multimedia applications such as audio and video streaming with mobile and static devices. Multimedia streaming applications need new approaches ...Over the past years, we have witnessed an explosive growth in the use of multimedia applications such as audio and video streaming with mobile and static devices. Multimedia streaming applications need new approaches to multimedia transmissions to meet the growing volume demand and quality expectations of multimedia traffic. This paper studies network coding which is a promising paradigm that has the potential to improve the performance of networks for multimedia streaming applications in terms of packet delivery ratio (PDR), latency and jitter. This paper examines several network coding protocols for ad hoc wireless mesh networks and compares their performance on multimedia streaming applications with optimized broadcast protocols, e.g., BCast, Simplified Multicast Forwarding (SMF), and Partial Dominant Pruning (PDP). The results show that the performance increases significantly with the Random Linear Network Coding (RLNC) scheme.展开更多
Wireless communication and broadcasting convergence networks provide a potential solution to greater traffic throughput in the future. In this paper, the throughput of a convergence network is analyzed based on the st...Wireless communication and broadcasting convergence networks provide a potential solution to greater traffic throughput in the future. In this paper, the throughput of a convergence network is analyzed based on the standardization project for specific requirements for local and metropolitan area networks in China, referred to as broadband wireless multimedia systems. The convergence network is modeled as a combination of a broadcasting channel and a multi-access channel with interference. The throughput is then given as a function of the time resource allocation by calculating the channel capacity with interference. The maximum throughput and the optimal time resource allocation are then determined for a given delay constraint and traffic requirements. The results give guidelines for time resource allocation and system design for convergence networks.展开更多
文摘Wireless sensor networks （WSNs） consist of sensor nodes that broadcast a message within a network. Efficient broadcasting is a key requirement in sensor networks and has been a focal point of research over the last few years. There are many challenging tasks in the network, including redundancy control and sensor node localization that mainly depend on broadcasting. In this paper, we propose a broadcasting algorithm to control redundancy and improve localization （BACRIL） in WSNs. The proposed algorithm incorporates the benefits of the gossip protocol for optimizing message broadcasting within the network. Simulation results show a controlled level of redundancy, which is up to 57.6% if the number of sensor nodes deployed in a 500 m×500 m area are increased from 50 to 500.
文摘Broadcasting is an important operation and been widely used in wireless sensor networks （WSNs）. These networks are power constrained as nodes operate with limited battery power. Wireless sensor networks are spatial graphs that have much more clustered and much high path-length characteristics. After considering energy- efficient broadcasting in such networks, by combining the small-world characteristic of WSNs and the properties of ant algorithm to quickly identify an optimal path, small-world power-aware broadcast algorithm is introduced and evaluated. Given different densities of network, simulation results show that our algorithm significantly improves life of networks and also reduces communication distances and power consumption.
文摘Broadcasting is a fundamental operation in any wireless networks, more so in wireless ad hoc sensor networks, where each sensor node has limited transmission range as well as battery power. Although broadcasting in wireless ad hoc sensor networks has many advantages but it can cause serious problems like-broadcast storm, which could cause a lot of contention, redundant retransmission, collision and most importantly, drain immense amount of energy from limited battery powered sensor nodes. In this work, our objective is to reduce the number of retransmission and energy consumption of sensor nodes by using the duty cycle property of wireless ad hoc sensor networks. We propose a preamble-based broadcasting technique for wireless ad hoc sensor networks. We show that in dense wireless ad hoc sensor networks a small size preamble can give maximum network-wide data dissemination rather than using the large preamble, which will only consume immense amount of energy during packet reception.
基金supported by the National Natural Science Foundation of China (60775047)Hunan Provincial Natural Science Foundation of China (07JJ6111)
文摘Due to the mutual interference and sharing of wireless links in TDMA wireless sensor networks, conflicts will occur when data messages are transmitting between nodes. The broadcast scheduling problem （BSP） is aimed to schedule each node in different slot of fixed length frame at least once, and the objective of BSP is to seek for the optimal feasible solution, which has the shortest length of frame slots, as well as the maximum node transmission. A two-stage mixed algorithm based on a fuzzy Hopfield neural network is proposed to solve this BSP in wireless sensor network. In the first stage, a modified sequential vertex coloring algorithm is adopted to obtain a minimal TDMA frame length. In the second stage, the fuzzy Hopfleld network is utilized to maximize the channel utilization ratio. Experimental results, obtained from the running on three benchmark graphs, show that the algorithm can achieve better performance with shorter frame length and higher channel utilizing ratio than other exiting BSP solutions.
基金supported by the National Natural Science Foundation of China (60502046, 60573034)863 Foundation of China (2007AA01Z215)
文摘Recently, network coding has been applied to the loss recovery of reliable broadcast transmission in wireless networks. Since it was proved that fi nding the optimal set of lost packets for XOR-ing is a complex NP-complete problem, the available time-based retransmission scheme and its enhanced retransmission scheme have exponential computational complexity and thus are not scalable to large networks. In this paper, we present an efficient heuristic scheme based on hypergraph coloring and also its enhanced heuristic scheme to improve the transmission efficiency. Basically, our proposed schemes fi rst create a hypergraph according to the packet-loss matrix. Then our schemes solve the problem of generating XORed packets by coloring the edges of hypergraph. Extensive simulation results demonstrate that, the heuristic scheme based on hypergraph coloring and its enhanced scheme can achieve almost the same transmission efficiency as the available ones, but have much lower computational complexity, which is very important for the wireless devices without high computation capacity.
文摘In this paper, we present a detailed analytical study of previously proposed variable preamble length-based broadcasting scheme for wireless sensor networks (WSNs). Analytical results show that in dense wireless sensor networks, broadcasting a packet with a small size preamble can significantly improve the energy conservation on already limited battery powered sensor nodes. For fairer comparison with variable preamble length-based broadcasting scheme, a comprehensive analytical study for an existing probability-based broadcasting scheme is also presented. Analytically calculated results show that variable preamble length-based broadcasting scheme is more energy-efficient than the probability-based broadcasting scheme.
文摘Deep learning-based Joint Source-Channel Coding(JSCC)is a crucial component in semantic communication,and recent research has made significant progress in adapting to different channels.In this paper,we propose a multi-stage progressive technique called Deep learning based Progressive Joint Source-Channel Coding(DP-JSCC).This approach partitions the source into multiple stages and transmits the signals continuously.The receiver gradually enhances the quality of image reconstruction by progressively receiving the signals,offering greater flexibility compared to existing dynamic rate transmission methods.The model adopts a lightweight architectural design,where we introduce an efficient module called the Inverted Shuffle Attention Bottleneck(ISAB)and incorporate self-attention mechanisms in the encoding and decoding process to capture signal correlations and establish long-range dependencies.Additionally,we introduce the Progressive Focus Weight Allocation(PFWA)method to improve the image reconstruction capability in progressive transmission tasks.These design enhance the expressive capacity of the model.Simulation results demonstrate that DP-JSCC can flexibly adjust the transmission rate according to requirements without the need for retraining or deployment,enabling continuous optimization of signals at different rates.Furthermore,compared to stateof-the-art JSCC methods,DP-JSCC exhibits advantages in terms of computational complexity,parameter count,and reconstruction performance.
基金supported in part by the National Key Research and Development Program of China(2023YFB2904703).
文摘1.Introduction It has been almost 60 years since the launch of Intelsat-I,the world’s first commercial satellite communications system.Over the past few decades,the development of satellite communications has been driven by both technological advancements and growing application demands,which have given rise to three primary services:broadcast,fixed satellite,and mobile satellite services[1].
基金supported in part by the National Natural Science Foundation of China under Grant No. 61032004the National High Technical Research and Development Program of China (863 Program) under Grants No. 2012AA121605,No. 2012AA01A503,No.2012AA01A510
文摘In traditional wireless broadcast networks,a corrupted packet must be retransmitted even if it has been lost by only one receiver.Obviously,this is not bandwidth-efficient for the receivers that already hold the retransmitted packet.Therefore,it is important to develop a method to realise efficient broadcast transmission.Network coding is a promising technique in this scenario.However,none of the proposed schemes achieves both high transmission efficiency and low computational complexity simultaneously so far.To address this problem,a novel Efficient Opportunistic Network Coding Retransmission(EONCR)scheme is proposed in this paper.This scheme employs a new packet scheduling algorithm which uses a Packet Distribution Matrix(PDM)directly to select the coded packets.The analysis and simulation results indicate that transmission efficiency of EONCR is over 0.1,more than the schemes proposed previously in some simulation conditions,and the computational overhead is reduced substantially.Hence,it has great application prospects in wireless broadcast networks,especially energyand bandwidth-limited systems such as satellite broadcast systems and Planetary Networks(PNs).
基金This work is financially supported by Beijing Municipal Natural Science Foundation(No.L202012)the Open Research Project of the State Key Laboratory of Media Convergence and Communication,Communication University of China(No.SKLMCC2020KF008)the Fundamental Research Funds for the Central Universities(No.2020RC05).
文摘Fast data synchronization in wireless ad hoc networks is a challenging and critical problem.It is fundamental for efficient information fusion,control and decision in distributed systems.Previously,distributed data synchronization was mainly studied in the latency-tolerant distributed databases,or assuming the general model of wireless ad hoc networks.In this paper,we propose a pair of linear network coding(NC)and all-to-all broadcast based fast data synchronization algorithms for wireless ad hoc networks whose topology is under operator’s control.We consider both data block selection and transmitting node selection for exploiting the benefits of NC.Instead of using the store-and-forward protocol as in the conventional uncoded approach,a compute-and-forward protocol is used in our scheme,which improves the transmission efficiency.The performance of the proposed algorithms is studied under different values of network size,network connection degree,and per-hop packet error rate.Simulation results demonstrate that our algorithms significantly reduce the times slots used for data synchronization compared with the baseline that does not use NC.
基金the National High Technology Research and Development Programme of China(No.2002AA142020)the National Natural Science Foundation of China(No.60475012)
文摘Directed diffusion is a data dissemination protocol for wireless sensor networks. In directed diffusion, flooding is used for dissemination of interest and exploratory data, which will bring broadcast storm resulting in substantial energy consumption of networks. A grid-based directed diffusion is presented to improve the energy efficiency of directed diffusion. Virtual geographic grid clusters are constructed by self-organization of nodes using geographic location information. The flooding of interest and exploratory data of original directed diffusion is limited in cluster head nodes. The simulation results and testbed experiments show that the method effectively reduces the network energy consumption. This gain is not achieved at the cost of either delivery ratio or the delay. Importantly, the decreased load also leads to a better delivery ratio and lower delay.
文摘Over the past years, we have witnessed an explosive growth in the use of multimedia applications such as audio and video streaming with mobile and static devices. Multimedia streaming applications need new approaches to multimedia transmissions to meet the growing volume demand and quality expectations of multimedia traffic. This paper studies network coding which is a promising paradigm that has the potential to improve the performance of networks for multimedia streaming applications in terms of packet delivery ratio (PDR), latency and jitter. This paper examines several network coding protocols for ad hoc wireless mesh networks and compares their performance on multimedia streaming applications with optimized broadcast protocols, e.g., BCast, Simplified Multicast Forwarding (SMF), and Partial Dominant Pruning (PDP). The results show that the performance increases significantly with the Random Linear Network Coding (RLNC) scheme.
基金Supported by ASTRI-Tsinghua BMC Joint Lab and NSFC/RGC Project (No.60618001)
文摘Wireless communication and broadcasting convergence networks provide a potential solution to greater traffic throughput in the future. In this paper, the throughput of a convergence network is analyzed based on the standardization project for specific requirements for local and metropolitan area networks in China, referred to as broadband wireless multimedia systems. The convergence network is modeled as a combination of a broadcasting channel and a multi-access channel with interference. The throughput is then given as a function of the time resource allocation by calculating the channel capacity with interference. The maximum throughput and the optimal time resource allocation are then determined for a given delay constraint and traffic requirements. The results give guidelines for time resource allocation and system design for convergence networks.
