Hybrid networking of power line and wireless communication can complement each other,save construction costs,improve network robustness,and has important value on the Internet of Things and smart grid.For power line a...Hybrid networking of power line and wireless communication can complement each other,save construction costs,improve network robustness,and has important value on the Internet of Things and smart grid.For power line and wireless dual-interface devices,a media access control(MAC)layer algorithm for hybrid communication is proposed,in which the stations can compete for two channels simultaneously.When a station obtains two channels at the same time,the station will randomly select a channel for transmission to ensure fairness,and reset the counters when the transmission is successful.In this paper,the performance of the unsaturated traffic model and counter spatial division is considered,and the throughput under coupling conditions is obtained.Finally,the simulation results show that the MAC layer algorithm based on the hybrid communication network can make full use of the advantages of the two channels,improve system throughput,and reduce transmission delay.展开更多
As a smart spectrum sharing technology, Cognitive Radio (CR) is becoming a hot topic in the field of wireless telecommunications. Besides providing traditional services, the cognitive radio network Media Access Contro...As a smart spectrum sharing technology, Cognitive Radio (CR) is becoming a hot topic in the field of wireless telecommunications. Besides providing traditional services, the cognitive radio network Media Access Control (MAC) layer is required to perform an entirely new set of functions for effective reusing spectrum opportunity, without causing any harmful interference to incumbents. Spectrum sensing management selects and optimizes sensing strategies and parameters by the selection of sensing mode, sensing period, sensing time, sensing channel, and sensing quiet period. Access control avoids collision with primary users mainly by cooperation access and transparent access. Dynamic spectrum allocation optimizes the allocation of uncertain spectrum for binary interference model and accumulative interference model. Security mechanism adds authentication and encryption mechanisms to MAC frame to defense MAC layer security attacks. Cross-layer design combines MAC layer information with physical layer or higher layers information, such as network layer, transmission layer, to achieve global optimization.展开更多
The attribute access methods of MAC layer in wireless communication network is researched. Aiming at conquering the problem of the shared ZigBee wireless channel resulting multi-channel device conflicts when using the...The attribute access methods of MAC layer in wireless communication network is researched. Aiming at conquering the problem of the shared ZigBee wireless channel resulting multi-channel device conflicts when using the data channel at the same time, therefore the protocol is improved and a method used to access the properties of ZigBee is proposed, and this method can be achieved to manage effectively for all the 29 properties MAC layer, save storage space and realize property maintenance and expansion.展开更多
Medium access control （MAC） protocols such as IEEE 802.11 are used in wireless networks for sharing of the wireless medium. The random nature of the protocol operation together with the inherent difficulty of monito...Medium access control （MAC） protocols such as IEEE 802.11 are used in wireless networks for sharing of the wireless medium. The random nature of the protocol operation together with the inherent difficulty of monitoring in the open poses significant challenges. All nodes are expected to comply with the protocol rules. But, some nodes in order to gain greater benefits misbehave by not complying with the rules. One such selfish misbehavior is waiting for smaller back-off intervals when compared to the other nodes in the same subnet. Such selfish misbehavior is being tackled in this paper. A diagnosis scheme and a penalty scheme are being proposed for overcoming such selfish-misbehavior at MAC layer of mobile ad hoc networks which could be extended to other types of networks also.展开更多
In the past decades,with the widespread implementation of wireless networks,such as the Internet of Things,an enormous demand for designing relative algorithms for various realistic scenarios has arisen.However,with t...In the past decades,with the widespread implementation of wireless networks,such as the Internet of Things,an enormous demand for designing relative algorithms for various realistic scenarios has arisen.However,with the widening of scales and deepening of network layers,it has become increasingly challenging to design such algorithms when the issues of message dissemination at high levels and the contention management at the physical layer are considered.Accordingly,the abstract medium access control(absMAC)layer,which was proposed in2009,is designed to solve this problem.Specifically,the absMAC layer consists of two basic operations for network agents:the acknowledgement operation to broadcast messages to all neighbors and the progress operation to receive messages from neighbors.The absMAC layer divides the wireless algorithm design into two independent and manageable components,i.e.,to implement the absMAC layer over a physical network and to solve higher-level problems based on the acknowledgement and progress operations provided by the absMAC layer,which makes the algorithm design easier and simpler.In this study,we consider the implementation of the absMAC layer under jamming.An efficient algorithm is proposed to implement the absMAC layer,attached with rigorous theoretical analyses and extensive simulation results.Based on the implemented absMAC layer,many high-level algorithms in non-jamming cases can be executed in a jamming network.展开更多
In a sustainable development context, the monitoring systems are essential to study the building energy performances. With the recent technology advances, these systems can be based on wireless sensor networks, where ...In a sustainable development context, the monitoring systems are essential to study the building energy performances. With the recent technology advances, these systems can be based on wireless sensor networks, where the energy efficiency is the main design challenge. To this end, most of the studies focus on low power Medium Access Control (MAC) protocols to reduce the overall energy consumption of a network. Nevertheless, the performances assessment of these protocols is generally not performed in a realistic way, and does not take into account the performances of the other layers of the OSI model. In this paper, we propose a cross-layer methodology to assess the real performances of a MAC protocol by taking into account the traffic volume, the synchronization losses and more particularly the physical layer performances through a Bit Error Rate (BER) criterion. The simulation results demonstrate clearly the physical layer impact on a sensor lifetime. Finally, the proposal of an energy efficient MAC protocol for a wireless sensor network dedicated to an application of building monitoring is proposed.展开更多
针对无线和电力线通信混合组网的信道竞争接入问题,提出了一种基于深度强化学习的电力线与无线双模通信的MAC接入算法。双模节点根据网络广播信息和信道使用等数据自适应接入双媒质信道。首先建立了基于双模通信网络交互和统计信息的双...针对无线和电力线通信混合组网的信道竞争接入问题,提出了一种基于深度强化学习的电力线与无线双模通信的MAC接入算法。双模节点根据网络广播信息和信道使用等数据自适应接入双媒质信道。首先建立了基于双模通信网络交互和统计信息的双模通信节点数据采集模型;接着定义了基于协作信息的深度强化学习(deep reinforcement learning,DRL)状态空间、动作空间和奖励,设计了联合α-公平效用函数和P坚持接入机制的节点决策流程,实现基于双深度Q网络(double deep Q-network,DDQN)的双模节点自适应接入算法;最后进行算法性能仿真和对比分析。仿真结果表明,提出的接入算法能够在保证双模网络和信道接入公平性的条件下,有效提高双模通信节点的接入性能。展开更多
For the high end-to-end channel capacity, the amplify-and-forward scheme multiple-hop MIMO relays system is considered. The distance between each transceiver is optimized to prevent some relays from being the bottlene...For the high end-to-end channel capacity, the amplify-and-forward scheme multiple-hop MIMO relays system is considered. The distance between each transceiver is optimized to prevent some relays from being the bottleneck and guarantee the high end-to-end channel capacity. However, in some cases, the location of relays can’t be set at the desired location, the transmit power of each relay should be optimized. Additionally, in order to achieve the higher end-to-end channel capacity, the distance and the transmit power are optimized simultaneously. We propose the Markov Chain Monte Carlo method to optimize both the distance and the transmit power in complex propagation environments. Moreover, when the system has no control over transmission of each relay, the interference signal is presented and the performance of system is deteriorated. The general protocol of control transmission for each relay on the MAC layer is analyzed and compared to the Carrier Sense Multiple Access-Collision Avoidance protocol. According to the number of relays, the Mac layer protocol for the highest end-to-end channel capacity is changed. We also analyze the end-to-end channel capacity when the number of antennas and relays tends to infinity.展开更多
针对PTP(precise time protocol)协议在应用层获取软件时间戳导致时钟同步精度下降的问题,提出一种基于MAC(media access control)层获取硬件时间戳的PTP同步优化方案。设计了以STM32F407微处理器为核心的PTP时钟应用平台,在MAC层实现...针对PTP(precise time protocol)协议在应用层获取软件时间戳导致时钟同步精度下降的问题,提出一种基于MAC(media access control)层获取硬件时间戳的PTP同步优化方案。设计了以STM32F407微处理器为核心的PTP时钟应用平台,在MAC层实现了硬件时间戳获取,避免了由于协议栈软件处理延时产生的不确定性;针对PTP时钟晶振老化导致的时间同步偏差及网络延迟抖动问题,采用迭代方法优化了本地时钟频率调节算法,提高了频率校正精度。经实际测试,主从时钟偏差的RMS(root mean square)优于20 ns,提升了时钟同步精度。展开更多
在VoWLAN(VoIP over WLAN)系统中,当周期性语音业务与随机性数据业务混合传输时,面临着信道能容纳的话路数少、语音业务与数据业务获得信道的机会不可控等问题。IEEE802.11e协议在传输周期的无竞争期(CFP)采用混合协调功能(HCF)来解决...在VoWLAN(VoIP over WLAN)系统中,当周期性语音业务与随机性数据业务混合传输时,面临着信道能容纳的话路数少、语音业务与数据业务获得信道的机会不可控等问题。IEEE802.11e协议在传输周期的无竞争期(CFP)采用混合协调功能(HCF)来解决语音业务QoS问题。研究在IEEE802.11e的HCF机制基础上,对媒质接入控制(MAC)层进行了改进,对CFP时段的上行周期性语音采用无竞争预约排队信道接入(CFRQCA)机制取代HCF受控信道接入(HCCA)方式,在CFP时段的下行语音接入采用M-M(Multicast-Multiplexing)机制;为了协调语音业务与数据业务的接入机会,论文中还提出了一种基于业务流量监测的接入机会自适应调度算法(AOASA);理论分析和仿真表明,无竞争预约排队机制和接入机会自适应调度算法能显著提高信道容纳的话路数。展开更多
为了延长网络的寿命,实现能量的高效利用是无线传感器网络应用的主要目标,MAC协议的能效性直接关系到网络的能耗,但采用分层方法的MAC协议无法实现最优的节能效果。本文基于跨层的方法提出了一种能量高效MAC(cross layer energy efficie...为了延长网络的寿命,实现能量的高效利用是无线传感器网络应用的主要目标,MAC协议的能效性直接关系到网络的能耗,但采用分层方法的MAC协议无法实现最优的节能效果。本文基于跨层的方法提出了一种能量高效MAC(cross layer energy efficient MAC,CLEE-MAC)协议。该协议在自适应S-MAC(adaptive sensor MAC,AS-MAC)协议基础上,通过利用路由层的路由表信息,改变AS-MAC协议的控制帧格式,有效解决了AS-MAC协议中因"强迫唤醒"造成的能量浪费问题,延长了网络的寿命。理论分析和仿真验证均表明,随着节点密度的增加,CLEE-MAC协议的节能增益随网络密度线性增大。展开更多
基金supported in part by the National Natural Science Foundation of China (Nos. 61601182)in part Natural Science Foundation of Hebei Province (F2017502059)in part by the Fundamental Research Funds for the Central Universities under Grant 2021MS070
文摘Hybrid networking of power line and wireless communication can complement each other,save construction costs,improve network robustness,and has important value on the Internet of Things and smart grid.For power line and wireless dual-interface devices,a media access control(MAC)layer algorithm for hybrid communication is proposed,in which the stations can compete for two channels simultaneously.When a station obtains two channels at the same time,the station will randomly select a channel for transmission to ensure fairness,and reset the counters when the transmission is successful.In this paper,the performance of the unsaturated traffic model and counter spatial division is considered,and the throughput under coupling conditions is obtained.Finally,the simulation results show that the MAC layer algorithm based on the hybrid communication network can make full use of the advantages of the two channels,improve system throughput,and reduce transmission delay.
基金supported by the National Natural Science Foundation of China under Grant No.60772110.
文摘As a smart spectrum sharing technology, Cognitive Radio (CR) is becoming a hot topic in the field of wireless telecommunications. Besides providing traditional services, the cognitive radio network Media Access Control (MAC) layer is required to perform an entirely new set of functions for effective reusing spectrum opportunity, without causing any harmful interference to incumbents. Spectrum sensing management selects and optimizes sensing strategies and parameters by the selection of sensing mode, sensing period, sensing time, sensing channel, and sensing quiet period. Access control avoids collision with primary users mainly by cooperation access and transparent access. Dynamic spectrum allocation optimizes the allocation of uncertain spectrum for binary interference model and accumulative interference model. Security mechanism adds authentication and encryption mechanisms to MAC frame to defense MAC layer security attacks. Cross-layer design combines MAC layer information with physical layer or higher layers information, such as network layer, transmission layer, to achieve global optimization.
文摘The attribute access methods of MAC layer in wireless communication network is researched. Aiming at conquering the problem of the shared ZigBee wireless channel resulting multi-channel device conflicts when using the data channel at the same time, therefore the protocol is improved and a method used to access the properties of ZigBee is proposed, and this method can be achieved to manage effectively for all the 29 properties MAC layer, save storage space and realize property maintenance and expansion.
文摘Medium access control （MAC） protocols such as IEEE 802.11 are used in wireless networks for sharing of the wireless medium. The random nature of the protocol operation together with the inherent difficulty of monitoring in the open poses significant challenges. All nodes are expected to comply with the protocol rules. But, some nodes in order to gain greater benefits misbehave by not complying with the rules. One such selfish misbehavior is waiting for smaller back-off intervals when compared to the other nodes in the same subnet. Such selfish misbehavior is being tackled in this paper. A diagnosis scheme and a penalty scheme are being proposed for overcoming such selfish-misbehavior at MAC layer of mobile ad hoc networks which could be extended to other types of networks also.
基金partially supported by the National Key R&D Program of China(No.2019YFB2102600)the National Natural Science Foundation of China(NSFC)(No.61971269)。
文摘In the past decades,with the widespread implementation of wireless networks,such as the Internet of Things,an enormous demand for designing relative algorithms for various realistic scenarios has arisen.However,with the widening of scales and deepening of network layers,it has become increasingly challenging to design such algorithms when the issues of message dissemination at high levels and the contention management at the physical layer are considered.Accordingly,the abstract medium access control(absMAC)layer,which was proposed in2009,is designed to solve this problem.Specifically,the absMAC layer consists of two basic operations for network agents:the acknowledgement operation to broadcast messages to all neighbors and the progress operation to receive messages from neighbors.The absMAC layer divides the wireless algorithm design into two independent and manageable components,i.e.,to implement the absMAC layer over a physical network and to solve higher-level problems based on the acknowledgement and progress operations provided by the absMAC layer,which makes the algorithm design easier and simpler.In this study,we consider the implementation of the absMAC layer under jamming.An efficient algorithm is proposed to implement the absMAC layer,attached with rigorous theoretical analyses and extensive simulation results.Based on the implemented absMAC layer,many high-level algorithms in non-jamming cases can be executed in a jamming network.
文摘In a sustainable development context, the monitoring systems are essential to study the building energy performances. With the recent technology advances, these systems can be based on wireless sensor networks, where the energy efficiency is the main design challenge. To this end, most of the studies focus on low power Medium Access Control (MAC) protocols to reduce the overall energy consumption of a network. Nevertheless, the performances assessment of these protocols is generally not performed in a realistic way, and does not take into account the performances of the other layers of the OSI model. In this paper, we propose a cross-layer methodology to assess the real performances of a MAC protocol by taking into account the traffic volume, the synchronization losses and more particularly the physical layer performances through a Bit Error Rate (BER) criterion. The simulation results demonstrate clearly the physical layer impact on a sensor lifetime. Finally, the proposal of an energy efficient MAC protocol for a wireless sensor network dedicated to an application of building monitoring is proposed.
文摘针对无线和电力线通信混合组网的信道竞争接入问题,提出了一种基于深度强化学习的电力线与无线双模通信的MAC接入算法。双模节点根据网络广播信息和信道使用等数据自适应接入双媒质信道。首先建立了基于双模通信网络交互和统计信息的双模通信节点数据采集模型;接着定义了基于协作信息的深度强化学习(deep reinforcement learning,DRL)状态空间、动作空间和奖励,设计了联合α-公平效用函数和P坚持接入机制的节点决策流程,实现基于双深度Q网络(double deep Q-network,DDQN)的双模节点自适应接入算法;最后进行算法性能仿真和对比分析。仿真结果表明,提出的接入算法能够在保证双模网络和信道接入公平性的条件下,有效提高双模通信节点的接入性能。
文摘For the high end-to-end channel capacity, the amplify-and-forward scheme multiple-hop MIMO relays system is considered. The distance between each transceiver is optimized to prevent some relays from being the bottleneck and guarantee the high end-to-end channel capacity. However, in some cases, the location of relays can’t be set at the desired location, the transmit power of each relay should be optimized. Additionally, in order to achieve the higher end-to-end channel capacity, the distance and the transmit power are optimized simultaneously. We propose the Markov Chain Monte Carlo method to optimize both the distance and the transmit power in complex propagation environments. Moreover, when the system has no control over transmission of each relay, the interference signal is presented and the performance of system is deteriorated. The general protocol of control transmission for each relay on the MAC layer is analyzed and compared to the Carrier Sense Multiple Access-Collision Avoidance protocol. According to the number of relays, the Mac layer protocol for the highest end-to-end channel capacity is changed. We also analyze the end-to-end channel capacity when the number of antennas and relays tends to infinity.
文摘针对PTP(precise time protocol)协议在应用层获取软件时间戳导致时钟同步精度下降的问题,提出一种基于MAC(media access control)层获取硬件时间戳的PTP同步优化方案。设计了以STM32F407微处理器为核心的PTP时钟应用平台,在MAC层实现了硬件时间戳获取,避免了由于协议栈软件处理延时产生的不确定性;针对PTP时钟晶振老化导致的时间同步偏差及网络延迟抖动问题,采用迭代方法优化了本地时钟频率调节算法,提高了频率校正精度。经实际测试,主从时钟偏差的RMS(root mean square)优于20 ns,提升了时钟同步精度。
文摘在VoWLAN(VoIP over WLAN)系统中,当周期性语音业务与随机性数据业务混合传输时,面临着信道能容纳的话路数少、语音业务与数据业务获得信道的机会不可控等问题。IEEE802.11e协议在传输周期的无竞争期(CFP)采用混合协调功能(HCF)来解决语音业务QoS问题。研究在IEEE802.11e的HCF机制基础上,对媒质接入控制(MAC)层进行了改进,对CFP时段的上行周期性语音采用无竞争预约排队信道接入(CFRQCA)机制取代HCF受控信道接入(HCCA)方式,在CFP时段的下行语音接入采用M-M(Multicast-Multiplexing)机制;为了协调语音业务与数据业务的接入机会,论文中还提出了一种基于业务流量监测的接入机会自适应调度算法(AOASA);理论分析和仿真表明,无竞争预约排队机制和接入机会自适应调度算法能显著提高信道容纳的话路数。
