IEEE802.11,known as WiFi has proliferated in the last decade.It can be found in smartphones,laptops,smart TVs and surveillance cameras.This popularity has revealed many issues in health,data privacy and security.In th...IEEE802.11,known as WiFi has proliferated in the last decade.It can be found in smartphones,laptops,smart TVs and surveillance cameras.This popularity has revealed many issues in health,data privacy and security.In this work,a WiFi measurement study has been conducted in Amman,the capital city of Jordan.An Android App has been written to harvest WiFi information of the transmitted frames of any surrounding Access points(APs).More than 240,000 APs information has been harvested in this work.The harvested data have been analyzed to find statistics ofWiFi devices in this city.Moreover,three power distribution models have been derived from the data for three different areas,closed,open and hybrid areas.In addition,the collected data revealed that the SSID can be leveraged as a landmark for the access points(APs).To this end,SSIDtrack algorithm is proposed to track shoppers/walkers in closed areas,such as malls to find their walking route utilizing only the SSID information collected from the surrounding area.The algorithm has been tested in two different malls that consist of four different floors.The accuracy recorded for the algorithm acceded 95%.展开更多
IEEE 802.16a is a wideband wireless access standard of the new generation,which is submitted by ITU on Apr. 2002.The standard advises to use OFDM or Single Carrier Frequency Domain Equalization in physical layer.As a ...IEEE 802.16a is a wideband wireless access standard of the new generation,which is submitted by ITU on Apr. 2002.The standard advises to use OFDM or Single Carrier Frequency Domain Equalization in physical layer.As a part of the national 863 research project,this paper investigates SC-FDE scheme of wideband wireless access systems.We set up an integrate simulation platform and put forward a SC-FDE scheme combining with MIMO and RS-CC to improve the system performance further.展开更多
Based on the structures of the short preamble and long preamble, which are defined for synchronization in IEEES02.16e specification, the robust synchronization algorithm for IEEES02.16e OFDM system is proposed. The co...Based on the structures of the short preamble and long preamble, which are defined for synchronization in IEEES02.16e specification, the robust synchronization algorithm for IEEES02.16e OFDM system is proposed. The correlations among the sample sequences in the preamble are investigated, especially the correlation between the first sample sequence and the last sample sequence in the long preamble. The conventional joint timing and frequency synchronization algorithm is reviewed based on the short preamble referring to the algorithm proposed by Schmidl, then a robust joint timing and frequency synchronization algorithm is proposed based on the long preamble. The simulations in the multi-path and frequency selective fading channel show that the proposed algorithm has improved the performances of timing metric plateau, timing offset and synchronization acquisition time even when signal-to-noise ratio is less than -5 dB.展开更多
The IEEE 802.11e standard is proposed to provide QoS support in WLAN by providing prioritized differentiation of traffic. Since all the stations in the same priority access category (AC) have the same set of parameter...The IEEE 802.11e standard is proposed to provide QoS support in WLAN by providing prioritized differentiation of traffic. Since all the stations in the same priority access category (AC) have the same set of parameters, when the number of stations increases, the probability of different stations in the same AC choosing the same values will increase, which will result in collisions. Random adaptive MAC (medium access control) parameters scheme (RAMPS) is proposed, which uses random adaptive MAC differentiation parameters instead of the static ones used in the 802.11e standard. The performance of RAMPS is compared with that of enhanced distributed coordination access (EDCA) using NS2. The results show that RAMPS can reduce collision rate of the AC and improve the throughput by using adaptive random contention window size and inter-frame spacing values. RAMPS ensures that at any given time, several flows of the same priority have different MAC parameter values. By using the random offset for the inter-frame spacing value and the backoff time, RAMPS can provide intra-AC differentiation. The simulation results show that RAMPS outperforms EDCA in terms of both throughput and end-to-end delay irrespective of the traffic load.展开更多
Wireless Body Area Network (WBAN) is considered to apply to both medical healthcare and entertainment applications. A requirement for each application is different, i.e. high reliability for medical healthcare whereas...Wireless Body Area Network (WBAN) is considered to apply to both medical healthcare and entertainment applications. A requirement for each application is different, i.e. high reliability for medical healthcare whereas high throughput for entertainment application. However, for both applications, low energy consumption is requested. Multiple hops technics have been researching in many fields of wireless system, e.g., ad hod, mobile, ITS etc. and its energy-efficiency is reported to be high. We propose the multiple hops technic for WBAN, however, WBAN is different to another systems, almost sensors forward the vital data packet of another sensors while sensing and generating the data packet of itself. Therefore, according to a packet generation rate of all sensors, probabilities of successful transmission and packet loss because of collision, timeout and overflow, are changed. It means that the vital data is lost and the transmit power is wasted due to packet loss. In order to obtain the highest throughput and save the power, the successful transmission probability is analyzed and the packet generation rate is optimized for multiple hops WBAN that using CSMA/CA based on IEEE802.15.6. The numerical calculation result indicates that the optimized packet generation rate depends on the system model. Moreover, the relation between the system model, the optimized packet generation rate and the throughput is discussed in the paper.展开更多
Check the CES TEMS Author’s Kit at http://www.cestems.org for the latest details.CES Transactions on Electrical Machines and Systems(CES TEMS) is an international quarterly journal, which is published by the China El...Check the CES TEMS Author’s Kit at http://www.cestems.org for the latest details.CES Transactions on Electrical Machines and Systems(CES TEMS) is an international quarterly journal, which is published by the China Electrotechnical Society (CES)and the Institute of Electrical Engineering of the Chinese Academy of Sciences, and technically co-sponsored by IEEE Power Electronics Society (IEEE PELS).展开更多
Check the CES TEMS Author’s Kit at http://www.cestems.org for the latest details.CES Transactions on Electrical Machines and Systems(CES TEMS) is an international quarterly journal,which is published by the China Ele...Check the CES TEMS Author’s Kit at http://www.cestems.org for the latest details.CES Transactions on Electrical Machines and Systems(CES TEMS) is an international quarterly journal,which is published by the China Electrotechnical Society (CES)and the Institute of Electrical Engineering of the Chinese Academy of Sciences,and technically co-sponsored by IEEE Power Electronics Society (IEEE PELS).CES TEMS is indexed by ESCI,EI,Scopus,IEEE Xplore,INSPEC,DOAJ,CSTPCD,CSCD and Google Scholar etc..展开更多
Several optimization methods,such as Particle Swarm Optimization(PSO)and Genetic Algorithm(GA),are used to select the most suitable Static Synchronous Compensator(STATCOM)technology for the optimal operation of the po...Several optimization methods,such as Particle Swarm Optimization(PSO)and Genetic Algorithm(GA),are used to select the most suitable Static Synchronous Compensator(STATCOM)technology for the optimal operation of the power system,as well as to determine its optimal location and size to minimize power losses.An IEEE 14 bus system,integrating three wind turbines based on Squirrel Cage Induction Generators(SCIGs),is used to test the applicability of the proposed algorithms.The results demonstrate that these algorithms are capable of selecting the most appropriate technology while optimally sizing and locating the STATCOM to reduce power losses in the network.Specifically,the optimized STATCOM allocation using the Particle Swarm Optimization(PSO)achieves a 7.44%reduction in total active power loss compared to the optimized allocation using the Genetic Algorithm(GA).Furthermore,the voltage magnitudes at buses 4,9,and 10,which initially had exceeded the upper voltage limit,were reduced and brought within acceptable ranges,thereby improving the system’s overall voltage profile.Consequently,the optimal allocation of the STATCOM significantly enhances the efficiency and performance of the power network.展开更多
With the exponential growth of mobile terminals and the widespread adoption of Internet of Things(IoT)technologies,an increasing number of devices rely on wireless local area networks(WLAN)for data transmission.To add...With the exponential growth of mobile terminals and the widespread adoption of Internet of Things(IoT)technologies,an increasing number of devices rely on wireless local area networks(WLAN)for data transmission.To address this demand,deploying more access points(APs)has become an inevitable trend.While this approach enhances network coverage and capacity,it also exacerbates co-channel interference(CCI).The multi-AP cooperation introduced in IEEE 802.11be(Wi-Fi 7)represents a paradigm shift from conventional single-AP architectures,offering a novel solution to CCI through joint resource scheduling across APs.However,designing efficient cooperation mechanisms and achieving optimal resource allocation in dense AP environment remain critical research challenges.To mitigate CCI in high-density WLANs,this paper proposes a radio resource allocation method based on 802.11be multi-AP cooperation.First,to reduce the network overhead associated with centralized AP management,we introduce a distributed interference-aware AP clustering method that groups APs into cooperative sets.Second,methods for multi-AP cooperation information exchange,and cooperation transmission processes are designed.To support network state collection,capability advertisement,and cooperative trigger execution at the protocol level,this paper enhances the 802.11 frame structure with dedicated fields for multi-AP cooperation.Finally,considering the mutual influence between power and channel allocation,this paper proposes a joint radio resource allocation algorithm that employs an enhanced genetic algorithm for resource unit(RU)allocation and Q-learning for power control,interconnected via an inner-outer dual-loop architecture.Simulation results demonstrate the effectiveness of the proposed CCI avoidance mechanism and radio resource allocation algorithm in enhancing throughput in dense WLAN scenarios.展开更多
This study introduces the Smart Exponential-Threshold-Linear with Double Deep Q-learning Network(SETL-DDQN)and an extended Gumbel distribution method,designed to optimize the Contention Window(CW)in IEEE 802.11 networ...This study introduces the Smart Exponential-Threshold-Linear with Double Deep Q-learning Network(SETL-DDQN)and an extended Gumbel distribution method,designed to optimize the Contention Window(CW)in IEEE 802.11 networks.Unlike conventional Deep Reinforcement Learning(DRL)-based approaches for CW size adjustment,which often suffer from overestimation bias and limited exploration diversity,leading to suboptimal throughput and collision performance.Our framework integrates the Gumbel distribution and extreme value theory to systematically enhance action selection under varying network conditions.First,SETL adopts a DDQN architecture(SETL-DDQN)to improve Q-value estimation accuracy and enhance training stability.Second,we incorporate a Gumbel distribution-driven exploration mechanism,forming SETL-DDQN(Gumbel),which employs the extreme value theory to promote diverse action selection,replacing the conventional-greedy exploration that undergoes early convergence to suboptimal solutions.Both models are evaluated through extensive simulations in static and time-varying IEEE 802.11 network scenarios.The results demonstrate that our approach consistently achieves higher throughput,lower collision rates,and improved adaptability,even under abrupt fluctuations in traffic load and network conditions.In particular,the Gumbel-based mechanism enhances the balance between exploration and exploitation,facilitating faster adaptation to varying congestion levels.These findings position Gumbel-enhanced DRL as an effective and robust solution for CW optimization in wireless networks,offering notable gains in efficiency and reliability over existing methods.展开更多
This Special Topic of the Journal of Semiconductors(JOS)features expanded versions of key articles presented at the 2024 IEEE International Conference on Integrated Circuits Technologies and Applications(ICTA),which w...This Special Topic of the Journal of Semiconductors(JOS)features expanded versions of key articles presented at the 2024 IEEE International Conference on Integrated Circuits Technologies and Applications(ICTA),which was held in Hangzhou,Zhejiang,China,from October 25 to 27,2024.展开更多
Check the CES TEMS Author’s Kit at http://www.cestems.org for the latest details.CES Transactions on Electrical Machines and Systems(CES TEMS)is an international quarterly journal,which is published by the China Elec...Check the CES TEMS Author’s Kit at http://www.cestems.org for the latest details.CES Transactions on Electrical Machines and Systems(CES TEMS)is an international quarterly journal,which is published by the China Electrotechnical Society(CES)and the Institute of Electrical Engineering of the Chinese Academy of Sciences,and technically co-sponsored by IEEE Power Electronics Society(IEEE PELS).CES TEMS is indexed by ESCI,EI,Scopus,IEEE Xplore,INSPEC,DOAJ,CSTPCD,CSCD and Google Scholar etc..展开更多
基金This work is funded by Al-Zaytoonah University of Jordan under project name“miniature distributed architecture for massive data processing”with the grant number 15/12/2019-2020。
文摘IEEE802.11,known as WiFi has proliferated in the last decade.It can be found in smartphones,laptops,smart TVs and surveillance cameras.This popularity has revealed many issues in health,data privacy and security.In this work,a WiFi measurement study has been conducted in Amman,the capital city of Jordan.An Android App has been written to harvest WiFi information of the transmitted frames of any surrounding Access points(APs).More than 240,000 APs information has been harvested in this work.The harvested data have been analyzed to find statistics ofWiFi devices in this city.Moreover,three power distribution models have been derived from the data for three different areas,closed,open and hybrid areas.In addition,the collected data revealed that the SSID can be leveraged as a landmark for the access points(APs).To this end,SSIDtrack algorithm is proposed to track shoppers/walkers in closed areas,such as malls to find their walking route utilizing only the SSID information collected from the surrounding area.The algorithm has been tested in two different malls that consist of four different floors.The accuracy recorded for the algorithm acceded 95%.
基金part of National 863 Project numbering 2002AA123046
文摘IEEE 802.16a is a wideband wireless access standard of the new generation,which is submitted by ITU on Apr. 2002.The standard advises to use OFDM or Single Carrier Frequency Domain Equalization in physical layer.As a part of the national 863 research project,this paper investigates SC-FDE scheme of wideband wireless access systems.We set up an integrate simulation platform and put forward a SC-FDE scheme combining with MIMO and RS-CC to improve the system performance further.
文摘Based on the structures of the short preamble and long preamble, which are defined for synchronization in IEEES02.16e specification, the robust synchronization algorithm for IEEES02.16e OFDM system is proposed. The correlations among the sample sequences in the preamble are investigated, especially the correlation between the first sample sequence and the last sample sequence in the long preamble. The conventional joint timing and frequency synchronization algorithm is reviewed based on the short preamble referring to the algorithm proposed by Schmidl, then a robust joint timing and frequency synchronization algorithm is proposed based on the long preamble. The simulations in the multi-path and frequency selective fading channel show that the proposed algorithm has improved the performances of timing metric plateau, timing offset and synchronization acquisition time even when signal-to-noise ratio is less than -5 dB.
基金Project(60673164) supported by the National Natural Science Foundation of ChinaProject(06JJ10009) supported by the Natural Science Foundation of Hunan Province, China+2 种基金Project(20060533057) supported by the Specialized Research Fund for the Doctoral Program of Higher Education of ChinaProject(2008CB317107) supported by the Major State Basic Research and Development Program of ChinaProject(NCET-05-0683) supported by the Program for New Century Excellent Talents in University
文摘The IEEE 802.11e standard is proposed to provide QoS support in WLAN by providing prioritized differentiation of traffic. Since all the stations in the same priority access category (AC) have the same set of parameters, when the number of stations increases, the probability of different stations in the same AC choosing the same values will increase, which will result in collisions. Random adaptive MAC (medium access control) parameters scheme (RAMPS) is proposed, which uses random adaptive MAC differentiation parameters instead of the static ones used in the 802.11e standard. The performance of RAMPS is compared with that of enhanced distributed coordination access (EDCA) using NS2. The results show that RAMPS can reduce collision rate of the AC and improve the throughput by using adaptive random contention window size and inter-frame spacing values. RAMPS ensures that at any given time, several flows of the same priority have different MAC parameter values. By using the random offset for the inter-frame spacing value and the backoff time, RAMPS can provide intra-AC differentiation. The simulation results show that RAMPS outperforms EDCA in terms of both throughput and end-to-end delay irrespective of the traffic load.
文摘Wireless Body Area Network (WBAN) is considered to apply to both medical healthcare and entertainment applications. A requirement for each application is different, i.e. high reliability for medical healthcare whereas high throughput for entertainment application. However, for both applications, low energy consumption is requested. Multiple hops technics have been researching in many fields of wireless system, e.g., ad hod, mobile, ITS etc. and its energy-efficiency is reported to be high. We propose the multiple hops technic for WBAN, however, WBAN is different to another systems, almost sensors forward the vital data packet of another sensors while sensing and generating the data packet of itself. Therefore, according to a packet generation rate of all sensors, probabilities of successful transmission and packet loss because of collision, timeout and overflow, are changed. It means that the vital data is lost and the transmit power is wasted due to packet loss. In order to obtain the highest throughput and save the power, the successful transmission probability is analyzed and the packet generation rate is optimized for multiple hops WBAN that using CSMA/CA based on IEEE802.15.6. The numerical calculation result indicates that the optimized packet generation rate depends on the system model. Moreover, the relation between the system model, the optimized packet generation rate and the throughput is discussed in the paper.
文摘Check the CES TEMS Author’s Kit at http://www.cestems.org for the latest details.CES Transactions on Electrical Machines and Systems(CES TEMS) is an international quarterly journal, which is published by the China Electrotechnical Society (CES)and the Institute of Electrical Engineering of the Chinese Academy of Sciences, and technically co-sponsored by IEEE Power Electronics Society (IEEE PELS).
文摘Check the CES TEMS Author’s Kit at http://www.cestems.org for the latest details.CES Transactions on Electrical Machines and Systems(CES TEMS) is an international quarterly journal,which is published by the China Electrotechnical Society (CES)and the Institute of Electrical Engineering of the Chinese Academy of Sciences,and technically co-sponsored by IEEE Power Electronics Society (IEEE PELS).CES TEMS is indexed by ESCI,EI,Scopus,IEEE Xplore,INSPEC,DOAJ,CSTPCD,CSCD and Google Scholar etc..
文摘Several optimization methods,such as Particle Swarm Optimization(PSO)and Genetic Algorithm(GA),are used to select the most suitable Static Synchronous Compensator(STATCOM)technology for the optimal operation of the power system,as well as to determine its optimal location and size to minimize power losses.An IEEE 14 bus system,integrating three wind turbines based on Squirrel Cage Induction Generators(SCIGs),is used to test the applicability of the proposed algorithms.The results demonstrate that these algorithms are capable of selecting the most appropriate technology while optimally sizing and locating the STATCOM to reduce power losses in the network.Specifically,the optimized STATCOM allocation using the Particle Swarm Optimization(PSO)achieves a 7.44%reduction in total active power loss compared to the optimized allocation using the Genetic Algorithm(GA).Furthermore,the voltage magnitudes at buses 4,9,and 10,which initially had exceeded the upper voltage limit,were reduced and brought within acceptable ranges,thereby improving the system’s overall voltage profile.Consequently,the optimal allocation of the STATCOM significantly enhances the efficiency and performance of the power network.
基金supported by National Natural Science Foundation of China(No.62201074),Reliable Mechanism for Edge Collaboration Service in Highly Dynamic Scenarios.
文摘With the exponential growth of mobile terminals and the widespread adoption of Internet of Things(IoT)technologies,an increasing number of devices rely on wireless local area networks(WLAN)for data transmission.To address this demand,deploying more access points(APs)has become an inevitable trend.While this approach enhances network coverage and capacity,it also exacerbates co-channel interference(CCI).The multi-AP cooperation introduced in IEEE 802.11be(Wi-Fi 7)represents a paradigm shift from conventional single-AP architectures,offering a novel solution to CCI through joint resource scheduling across APs.However,designing efficient cooperation mechanisms and achieving optimal resource allocation in dense AP environment remain critical research challenges.To mitigate CCI in high-density WLANs,this paper proposes a radio resource allocation method based on 802.11be multi-AP cooperation.First,to reduce the network overhead associated with centralized AP management,we introduce a distributed interference-aware AP clustering method that groups APs into cooperative sets.Second,methods for multi-AP cooperation information exchange,and cooperation transmission processes are designed.To support network state collection,capability advertisement,and cooperative trigger execution at the protocol level,this paper enhances the 802.11 frame structure with dedicated fields for multi-AP cooperation.Finally,considering the mutual influence between power and channel allocation,this paper proposes a joint radio resource allocation algorithm that employs an enhanced genetic algorithm for resource unit(RU)allocation and Q-learning for power control,interconnected via an inner-outer dual-loop architecture.Simulation results demonstrate the effectiveness of the proposed CCI avoidance mechanism and radio resource allocation algorithm in enhancing throughput in dense WLAN scenarios.
文摘This study introduces the Smart Exponential-Threshold-Linear with Double Deep Q-learning Network(SETL-DDQN)and an extended Gumbel distribution method,designed to optimize the Contention Window(CW)in IEEE 802.11 networks.Unlike conventional Deep Reinforcement Learning(DRL)-based approaches for CW size adjustment,which often suffer from overestimation bias and limited exploration diversity,leading to suboptimal throughput and collision performance.Our framework integrates the Gumbel distribution and extreme value theory to systematically enhance action selection under varying network conditions.First,SETL adopts a DDQN architecture(SETL-DDQN)to improve Q-value estimation accuracy and enhance training stability.Second,we incorporate a Gumbel distribution-driven exploration mechanism,forming SETL-DDQN(Gumbel),which employs the extreme value theory to promote diverse action selection,replacing the conventional-greedy exploration that undergoes early convergence to suboptimal solutions.Both models are evaluated through extensive simulations in static and time-varying IEEE 802.11 network scenarios.The results demonstrate that our approach consistently achieves higher throughput,lower collision rates,and improved adaptability,even under abrupt fluctuations in traffic load and network conditions.In particular,the Gumbel-based mechanism enhances the balance between exploration and exploitation,facilitating faster adaptation to varying congestion levels.These findings position Gumbel-enhanced DRL as an effective and robust solution for CW optimization in wireless networks,offering notable gains in efficiency and reliability over existing methods.
文摘This Special Topic of the Journal of Semiconductors(JOS)features expanded versions of key articles presented at the 2024 IEEE International Conference on Integrated Circuits Technologies and Applications(ICTA),which was held in Hangzhou,Zhejiang,China,from October 25 to 27,2024.
文摘Check the CES TEMS Author’s Kit at http://www.cestems.org for the latest details.CES Transactions on Electrical Machines and Systems(CES TEMS)is an international quarterly journal,which is published by the China Electrotechnical Society(CES)and the Institute of Electrical Engineering of the Chinese Academy of Sciences,and technically co-sponsored by IEEE Power Electronics Society(IEEE PELS).CES TEMS is indexed by ESCI,EI,Scopus,IEEE Xplore,INSPEC,DOAJ,CSTPCD,CSCD and Google Scholar etc..