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Energy efficiency aware dynamic rate and power adaptation in carrier sensing based WLANs under Rayleigh fading and shadowing
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作者 Md.Forkan Uddin 《Digital Communications and Networks》 SCIE CSCD 2024年第4期918-933,共16页
We consider the problem of energy efficiency aware dynamic adaptation of data transmission rate and transmission power of the users in carrier sensing based Wireless Local Area Networks(WLANs)in the presence of path l... We consider the problem of energy efficiency aware dynamic adaptation of data transmission rate and transmission power of the users in carrier sensing based Wireless Local Area Networks(WLANs)in the presence of path loss,Rayleigh fading and log-normal shadowing.For a data packet transmission,we formulate an optimization problem,solve the problem,and propose a rate and transmission power adaptation scheme with a restriction methodology of data packet transmission for achieving the optimal energy efficiency.In the restriction methodology of data packet transmission,a user does not transmit a data packet if the instantaneous channel gain of the user is lower than a threshold.To evaluate the performance of the proposed scheme,we develop analytical models for computing the throughput and energy efficiency of WLANs under the proposed scheme considering a saturation traffic condition.We then validate the analytical models via simulation.We find that the proposed scheme provides better throughput and energy efficiency with acceptable throughput fairness if the restriction methodology of data packet transmission is included.By means of the analytical models and simulations,we demonstrate that the proposed scheme provides significantly higher throughput,energy efficiency and fairness index than a traditional non-adaptive scheme and an existing most relevant adaptive scheme.Throughput and energy efficiency gains obtained by the proposed scheme with respect to the existing adapting scheme are about 75%and 103%,respectively,for a fairness index of 0.8.We also study the effect of various system parameters on throughput and energy efficiency and provide various engineering insights. 展开更多
关键词 carrier sense multiple access Energy efficiency Fading and shadowing Rate and power adaptation THROUGHPUT Wireless local area networks
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Using CSMA/CD for Ethernet Passive Optical Network (EPON) 被引量:1
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作者 季晓飞 范戈 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第2期25-28,共4页
Using CSMA/CD for EPON can eliminate the augmentations, such as multi-point control protocol and point-to-point emulation, added to the existing 802.3 architecture due to the incompatibility of PON to Ethernet. Both f... Using CSMA/CD for EPON can eliminate the augmentations, such as multi-point control protocol and point-to-point emulation, added to the existing 802.3 architecture due to the incompatibility of PON to Ethernet. Both full-duplex EPON system and half-duplex EPON system using CSMA/CD were proposed. In the full-duplex EPON, CSMA/CD is used as the upstream MAC protocol. In the half-duplex EPON system, both upstream and downstream traffic contend for the optical channel through CSMA/CD protocol. The upstream lightwave redirection and collision detection techniques were given. By the analysis and simulation, the throughput performance of the half-duplex EPON system is proven to be as well as that of the existing high speed half-duplex Ethernet LAN. 展开更多
关键词 ETHERNET passive optical network carrier sense multiple access optical access network
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Modeling and Simulation of P-Aloha,CSMA /CA and MACAW Protocols for Underwater Acoustic Channel 被引量:1
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作者 DAO Van-phuong 左加阔 +3 位作者 赵力 NGUYEN Dang-nam 邹采荣 孙剑 《Journal of Donghua University(English Edition)》 EI CAS 2015年第1期35-40,共6页
Medium access control( MAC) protocol of underwater acoustic communication network is a key technology for underwater acoustic networks( UANs). Most of the MAC protocols for wireless terrestrial communication networks ... Medium access control( MAC) protocol of underwater acoustic communication network is a key technology for underwater acoustic networks( UANs). Most of the MAC protocols for wireless terrestrial communication networks have been designed with negligible propagation delay. If it is deployed directly in an underwater environment,the UANs will perform inefficiently. In this paper,the characteristics of underwater acoustic channel are modeled and simulated by using the OPNET simulation tool,which are the speed of sound, propagation loss, and four sources for ambient noise: the turbulence,shipping,wind driven waves and thermal noise. The performance of pure Aloha( P-Aloha),carrier sense multiple access with collision avoidance( CSMA / CA) and multiple access collision avoidance for wireless local area network( MACAW) protocols in underwater acoustic channel environment are evaluated. The different performance of protocols in underwater environment is compared in the simulation. 展开更多
关键词 underwater acoustic channel OPNET simulation medium access control(MAC) protocol pure Aloha(P-Aloha) protocol carrier sense multiple access with collision avoidance(CSMA /CA) protocol multiple access collision avoidance for wireless local area network(MACAW) protocol
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Analysis of Multi-Channel and Slotted Random Multi-Access Protocol with Two-Dimensional Probability for Ad Hoc Network 被引量:4
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作者 周宁玉 赵东风 丁洪伟 《Tsinghua Science and Technology》 SCIE EI CAS 2008年第6期747-753,共7页
A higher quality of service (QoS) is provided for ad hoc networks through a multi-channel and slotted random multi-access (MSRM) protocol with two-dimensional probability. For this protocol, the system time is slo... A higher quality of service (QoS) is provided for ad hoc networks through a multi-channel and slotted random multi-access (MSRM) protocol with two-dimensional probability. For this protocol, the system time is slotted into a time slot with high channel utilization realized by the choice of two parameters p1 and p2, and the channel load equilibrium. The protocol analyzes the throughput of the MSRM protocol for a load equilibrium state and the throughput based on priority. Simulations agree with the theoretical analysis. The simulations also show that the slotted-time system is better than the continuous-time system. 展开更多
关键词 MULTI-CHANNEL slotted random multi-access two-dimensional probability carrier sense multiple access quality of service ad hoc networks
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