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A CSMA/CA based MAC protocol for hybrid Power-line/Visible-light communication networks:Design and analysis
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作者 Sheng Hao Huyin Zhang +2 位作者 Fei Yang Chenghao Li Jing Wang 《Digital Communications and Networks》 SCIE CSCD 2024年第2期481-497,共17页
Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and har... Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and hardware efficiency.Current research on HPVC networks focuses on the performance analysis and optimization of the Physical(PHY)layer,where the Power Line Communication(PLC)component only serves as the backbone to provide power to light Emitting Diode(LED)devices.So designing a Media Access Control(MAC)protocol remains a great challenge because it allows both PLC and Visible Light Communication(VLC)components to operate data transmission,i.e.,to achieve a true HPVC network CC.To solve this problem,we propose a new HPC network MAC protocol(HPVC MAC)based on Carrier Sense Multiple Access/Collision Avoidance(CSMA/CA)by combining IEEE 802.15.7 and IEEE 1901 standards.Firstly,we add an Additional Assistance(AA)layer to provide the channel selection strategies for sensor stations,so that they can complete data transmission on the selected channel via the specified CSMA/CA mechanism,respectively.Based on this,we give a detailed working principle of the HPVC MAC,followed by the construction of a joint analytical model for mathematicalmathematical validation of the HPVC MAC.In the modeling process,the impacts of PHY layer settings(including channel fading types and additive noise feature),CSMA/CA mechanisms of 802.15.7 and 1901,and practical configurations(such as traffic rate,transit buffer size)are comprehensively taken into consideration.Moreover,we prove the proposed analytical model has the solvability.Finally,through extensive simulations,we characterize the HPVC MAC performance under different system parameters and verify the correctness of the corresponding analytical model with an average error rate of 4.62%between the simulation and analytical results. 展开更多
关键词 Hybrid power-line/Visible light communication (HPVC)networks mac protocol CSMA/CA IEEE 802.15.7 IEEE 1901 Performance analysis
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Priority Based Energy Efficient MAC Protocol by Varying Data Ratefor Wireless Body Area Network
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作者 R.Sangeetha Usha Devi Gandhi 《Computer Systems Science & Engineering》 2024年第2期395-411,共17页
Wireless Body Area Network(WBAN)is a cutting-edge technology that is being used in healthcare applications to monitor critical events in the human body.WBAN is a collection of in-body and on-body sensors that monitor ... Wireless Body Area Network(WBAN)is a cutting-edge technology that is being used in healthcare applications to monitor critical events in the human body.WBAN is a collection of in-body and on-body sensors that monitor human physical parameters such as temperature,blood pressure,pulse rate,oxygen level,body motion,and so on.They sense the data and communicate it to the Body Area Network(BAN)Coordinator.The main challenge for the WBAN is energy consumption.These issues can be addressed by implementing an effective Medium Access Control(MAC)protocol that reduces energy consumption and increases network lifetime.The purpose of the study is to minimize the energy consumption and minimize the delay using IEEE 802.15.4 standard.In our proposed work,if any critical events have occurred the proposed work is to classify and prioritize the data.We gave priority to the highly critical data to get the Guarantee Tine Slots(GTS)in IEEE 802.15.4 standard superframe to achieve greater energy efficiency.The proposed MAC provides higher data rates for critical data based on the history and current condition and also provides the best reliable service to high critical data and critical data by predicting node similarity.As an outcome,we proposed a MAC protocol for Variable Data Rates(MVDR).When compared to existing MAC protocols,the MVDR performed very well with low energy intake,less interruption,and an enhanced packet-sharing ratio. 展开更多
关键词 Wireless Body Area Network(WBAN) IEEE 802.15.4 energy efficiency mac protocol ZIGBEE
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Energy Efficient MAC Protocol for Wireless Full-Duplex Networks 被引量:2
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作者 Yu Song Wangdong Qi Wenchi Cheng 《China Communications》 SCIE CSCD 2018年第1期35-44,共10页
The wireless full-duplex(FD) nodes can transmit and receive at the same time using the same frequency-band. Currently, the latest FD media access control(MAC) protocols mainly focus on how to convert the physical laye... The wireless full-duplex(FD) nodes can transmit and receive at the same time using the same frequency-band. Currently, the latest FD media access control(MAC) protocols mainly focus on how to convert the physical layer gains of FD nodes to the throughput gain of wireless FD networks, but pay little attention to the energy consumptions of FD nodes. In this paper, we propose an energy efficient FD MAC protocol. According to the values of self-interference cancellation coefficients corresponding to the nodes of each FD pair and the signal propagation attenuation, the proposed protocol can adaptively select the communication mode of the FD pair between the full-duplex and half-duplex. Also, the minimum transmit power for FD nodes can be obtained to achieve high energy efficiency. We develop an analytical model to characterize the performance of our protocol. The numerical results show that the proposed MAC protocol can optimize the system throughput and reduce the transmission energy consumptions of nodes simultaneously as compared with those of the existing works. 展开更多
关键词 wireless full-duplex networks mac protocol energy efficient self-interference cancellation coefficient
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Efficient MAC Protocols for Brain Computer Interface Applications 被引量:1
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作者 Shams Al Ajrawi Ramesh Rao Mahasweta Sarkar 《Computers, Materials & Continua》 SCIE EI 2021年第10期589-605,共17页
Brain computer interface(BCI)systems permit individuals with motor disorders to utilize their thoughts as a mean to control external devices.BCI is a promising interdisciplinary field that gained the attention of many... Brain computer interface(BCI)systems permit individuals with motor disorders to utilize their thoughts as a mean to control external devices.BCI is a promising interdisciplinary field that gained the attention of many researchers.Yet,the development of BCI systems is facing several challenges,such as network lifetime.The Medium Access Control(MAC)Protocol is the bottle-neck of network reliability.There are many MAC protocols that can be utilized for dependable transmission in BCI applications by altering their control parameters.However,modifying these parameters is another source of concern due to the scarcity in knowledge about the effect of modification.Also,there is still no instrument that can receive and actualize these parameters on transmitters embedded inside the cerebrum.In this paper,we propose two novel MAC protocols using passive UHF-RFID,the proposed protocols provide efficient and reliable communication between the transmitters and the receiver.The UHF-RFID transmitters were used because they are energy efficient which makes them compatible with BCI application.The first protocol is designed for the EEG signals.While the second protocol was designed for the ECoG signals.The evaluation results showed the validity of the proposed protocols in terms of network performance.The results also proved that the protocols are suitable and reliable for designing efficient BCI applications. 展开更多
关键词 Brain-computer interface mac protocol UHF-RFID TDMA FDMA CSMA
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Data Concurrent Transmission MAC Protocol for Application Oriented Underwater Acoustic Sensor Networks 被引量:1
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作者 Xiaoxiao Zhuo Hong Yang +3 位作者 Meiyan Liu Yan Wei Guanding Yu Fengzhong Qu 《China Communications》 SCIE CSCD 2022年第10期220-237,共18页
With the increasing demand for marine exploration, underwater acoustic sensor networks (UASNs) are prone to have the characteristics of large-scale, long term monitoring, and high data traffic load. Underwater media a... With the increasing demand for marine exploration, underwater acoustic sensor networks (UASNs) are prone to have the characteristics of large-scale, long term monitoring, and high data traffic load. Underwater media access control (MAC) protocols, which allow multiple users to share the common medium fairly and efficiently, are essential for the performance of UASNs. However, the design of MAC protocols is confronted with the challenges of spatial unfairness, data eruption, and low energy efficiency. In this paper, we propose a novel data concurrent transmission (DCT) MAC protocol, which is able to exploit long propagation delay and conduct concurrent transmission. Specifically, we present the theoretical performance analysis of the proposed MAC protocol in detail and give an analytical solution of the success concurrent transmission probability between nodes. In addition, simulation results are provided to demonstrate that our proposed protocol is appropriate for UASNs and can significantly improve the performance in terms of network throughput and energy consumption. Finally, we give some typical future applications of UASNs and discuss the demands on MAC protocol design. 展开更多
关键词 underwater acoustic sensor networks mac protocols data concurrent transmission
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Design and Evaluation of CRDMAC: Circular RTR Directional MAC Protocol for WANETs
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作者 Lu Huang Li Jie +1 位作者 Dong Zhongping Ji Yusheng 《China Communications》 SCIE CSCD 2012年第6期1-13,共13页
Using directional antennas in Wireless Ad hoc Networks (WANETs) offers great potential of reducing the radio interference, and improving the communication throughput. Directional antennas, however, introduces new prob... Using directional antennas in Wireless Ad hoc Networks (WANETs) offers great potential of reducing the radio interference, and improving the communication throughput. Directional antennas, however, introduces new problems in the wireless Media Access Control (MAC), that is, the deafness and new hidden terminal problem, which may cause severe performance degradation. To solve the problems, we propose an effective Circular RTR Directional MAC (CRDMAC) protocol for WANETs by using a sub-transmission channel and Ready to Receive (RTR) packets, which modifies the IEEE 802.11 Distributed Coordinated Function (DCF). The sub-channel avoids collisions to other ongoing transmission, and the RTR packets notify the neighbor nodes that the mutual transmission has been finished. We evaluate the CRDMAC protocol through simulations and the results show that the proposed protocol outperforms existing DMAC (directional MAC) protocol and the CRCM (Circular RTS and CTS MAC) protocol in terms of throughput and packet drop rate. 展开更多
关键词 WANETs mac protocol directionalantenna DEAFNESS new hidden terminal
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A synchronous duty-cycled reservation based MAC protocol for underwater wireless sensor networks
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作者 Alak Roy Nityananda Sarma 《Digital Communications and Networks》 SCIE CSCD 2021年第3期385-398,共14页
To design an energy-efficient Medium Access Control(MAC)protocol for the Underwater Wireless Sensor Networks(UWSNs)is an urgent research issue since depleted batteries cannot be recharged or replaced in the underwater... To design an energy-efficient Medium Access Control(MAC)protocol for the Underwater Wireless Sensor Networks(UWSNs)is an urgent research issue since depleted batteries cannot be recharged or replaced in the underwater environment.Moreover,the underwater acoustic channels are affected by hindrances such as long propagation delay and limited bandwidth,which appear in the design of the MAC protocol for the UWSNs.The available MAC protocols for the terrestrial wireless sensor networks exhibit low performance in energy efficiency,throughput and reliability in the UWSNs,and cannot be used in the UWSNs directly because of their unique characteristics.This paper proposes a synchronous duty-cycled reservation-based MAC protocol named Ordered Contention MAC(OCMAC)protocol.The basic mechanism of this protocol is to schedule data transmission by transmitters through the scheduling of Ready To Send(RTS)frames.The protocol eliminates the possible collision during data transmission and improves communication efficiency.The paper analyzes the performance in energy efficiency,throughput and reliability of the protocol by modeling the queuing behavior of OCMAC with a Markov Chain process.Furthermore,the analytical model is validated through a simulation study.The analysis results demonstrated that while providing good throughput and reliability,OCMAC can achieve energy saving. 展开更多
关键词 Underwater wireless sensor networks mac protocol Energy efficiency THROUGHPUT RELIABILITY Acoustic communication OCmac
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A Performance Comparison of Two Real Time WLAN MAC Protocols
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作者 曹春生 李锋 张卫东 《Journal of Donghua University(English Edition)》 EI CAS 2007年第5期637-640,共4页
By modifying the IEEE 802.11 wireless local area network(WLAN) medium access protocol(MAC),a contention based and a polling based protocol are proposed to deal with the case every station possesses two classes of fram... By modifying the IEEE 802.11 wireless local area network(WLAN) medium access protocol(MAC),a contention based and a polling based protocol are proposed to deal with the case every station possesses two classes of frame in real time applications.Both protocols can ensure the real time frame only need to wait a determinable bounded time.These two protocols are introduced briefly and a performance comparison between them is made.Simulation results show that each protocol has advantage over the others in certain network condition. 展开更多
关键词 frame class mac protocol wireless LAN upper bound
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Design and analysis of MAC protocol for wireless ATM network 被引量:2
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作者 沙学军 徐玉滨 张乃通 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第4期42-46,共5页
Presents the new design of a reservation based medium access protocol,dynamic frame packet reservation multiple access (DF PRMA), for wireless ATM environments its mathematic model built, and analysis of such performa... Presents the new design of a reservation based medium access protocol,dynamic frame packet reservation multiple access (DF PRMA), for wireless ATM environments its mathematic model built, and analysis of such performance as delay and channel throughput its adaptbility to the fluctuation of traffic by controlling frame length dynamically and guarantee delay performance by forced collision and special reservarion slot. Thereby providing a limited access delay and QoS level and maintaining a resonable high channel throughput. 展开更多
关键词 mac protocol WIRELESS ATM DELAY channel THROUGHPUT
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A new multi-channel MAC protocol based on CDMA for ad hoc networks 被引量:1
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作者 贾旻 陈惠民 袁玉华 《Journal of Shanghai University(English Edition)》 CAS 2007年第2期174-177,共4页
This paper proposes a novel multichannel medium access control (MAC) protocol based on CDMA that improves network performance and reduces collision probability in wireless ad hoc networks. In the scheme, the code ch... This paper proposes a novel multichannel medium access control (MAC) protocol based on CDMA that improves network performance and reduces collision probability in wireless ad hoc networks. In the scheme, the code channel is divided into common channel, broadcast channel and several data channels. Simulation results show that the proposed protocol can achieve significantly better performance than the IEEE 802.11 standard. 展开更多
关键词 ad hoc networks medium access control mac protocol MULTICHANNEL CDMA
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A Priority-aware Frequency Domain Polling MAC Protocol for OFDMA-based Networks in Cyber-physical Systems 被引量:1
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作者 Meng Zheng Junru Lin +1 位作者 Wei Liang Haibin Yu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2015年第4期412-421,共10页
Wireless networking in cyber-physical systems (CPSs) is characteristically different from traditional wireless systems due to the harsh radio frequency environment and applications that impose high real-time and relia... Wireless networking in cyber-physical systems (CPSs) is characteristically different from traditional wireless systems due to the harsh radio frequency environment and applications that impose high real-time and reliability constraints. One of the fundamental considerations for enabling CPS networks is the medium access control protocol. To this end, this paper proposes a novel priority-aware frequency domain polling medium access control (MAC) protocol, which takes advantage of an orthogonal frequency-division multiple access (OFDMA) physical layer to achieve instantaneous priority-aware polling. Based on the polling result, the proposed work then optimizes the resource allocation of the OFDMA network to further improve the data reliability. Due to the non-polynomial-complete nature of the OFDMA resource allocation, we propose two heuristic rules, based on which an efficient solution algorithm to the OFDMA resource allocation problem is designed. Simulation results show that the reliability performance of CPS networks is significantly improved because of this work. © 2014 Chinese Association of Automation. 展开更多
关键词 Access control Embedded systems Frequency domain analysis Medium access control Network layers Orthogonal frequency division multiplexing POLYNOMIALS Real time systems Reliability Resource allocation Wireless networks
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Performance Analysis of MAC Protocol for LEO Satellite Networks 被引量:1
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作者 Mingxiang GUAN Ruichun WANG 《International Journal of Communications, Network and System Sciences》 2009年第8期786-791,共6页
Considering that weak channel collision detection ability, long propagation delay and heavy load in LEO satellite communications, a valid adaptive APRMA MAC protocol was proposed. Different access probability function... Considering that weak channel collision detection ability, long propagation delay and heavy load in LEO satellite communications, a valid adaptive APRMA MAC protocol was proposed. Different access probability functions for different services were obtained and appropriate access probabilities for voice and data users were updated slot by slot based on the estimation of the voice traffic and the channel status. In the proposed MAC protocol limited wireless resource is allocated reasonably by multiple users and high capacity was achieved. Three performance parameters: voice packet loss probability, average delay of data packets and throughput of data packets were considered in simulation. Finally simulation results demonstrated that the performance of system was improved by the APRMA compared with the conventional PRMA, with an acceptable trade-off between QoS of voice and delay of data. 展开更多
关键词 LEO SATELLITES Adaptive PACKET RESERVATION Multiple Access mac protocol
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Exploration of Energy Conservation MAC Protocol of WSNs for Ubiquitous Environment
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作者 WEI Wei QI Yong HOU Di 《Wuhan University Journal of Natural Sciences》 CAS 2008年第4期509-512,共4页
According to analyze the facade phenomenon of wire-less sensor networks(WSNs),this paper proposes a feasible method to state clearly and improve the power control efficiency of wire-less sensor networks(WSNs). One... According to analyze the facade phenomenon of wire-less sensor networks(WSNs),this paper proposes a feasible method to state clearly and improve the power control efficiency of wire-less sensor networks(WSNs). One of the crucial problems for WSNs is the design of medium access control (MAC) protocol. Our method want to adjust the activities of the MAC protocols control to achieve the enery conservation when the wireless communication module of sensor nodes is running, which is the major consumer of energy consumed by sensors energy. The energy efficiency of MAC protocol makes a strong impact on the network performance. To some extent,our research work describes and analyze the sources of energy consumption in MAC layer and simultaneously present an optimal method for the design of MAC protocol. Then we discusses some factors impacting on the performance of MAC protocol and metrics of performance evaluation. Eventually, the coming research direction is summarized. 展开更多
关键词 wireless sensor networks (WSNs) medium accesscontrol energy conservation medium access control(mac protocols
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QTDMAC:MAC protocol for QoS support in MANET using smart antennas
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作者 ZHANG Ying-chao GUAN Li-li 《重庆邮电大学学报(自然科学版)》 北大核心 2009年第2期262-266,共5页
Unlike directional antennas, smart antennas offer MANET (Mobile Ad hoc Net works) potential increases in their achievable throughput and capacity. Based on the development of smart antenna technology, we studied the M... Unlike directional antennas, smart antennas offer MANET (Mobile Ad hoc Net works) potential increases in their achievable throughput and capacity. Based on the development of smart antenna technology, we studied the MAC protocol for QoS support was studied, which becomes the hot issue in multimedia services. The protocol divides the channel into the data channel and the control channel, node sends forecast guarantee to compete the channel. And after completing the RTS / CTS handshake appointment, node is reserved for data transmission. Node can send Busy Tones to prevent the problem of the deafness nodes and hidden terminal. At last if the direct link between the sender and receiver has low quality and low rate, data packets may be delivered faster through a relay node. Through the analytical results, QTDMAC with the protocol IEEE802.1 and DMAC were compared. The QTDMAC protocol is proved the superiority in throughput and the real-time delay business. 展开更多
关键词 MANET网络 智能天线技术 QOS支持 mac协议 多媒体服务 议定书 定向天线 移动AD
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Energy Consumption and Fault Tolerance in the MAC Protocols for WSN
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作者 Ridha Azizi 《Journal of Computer and Communications》 2015年第6期118-130,共13页
Wireless sensor networks are currently experiencing widespread enthusiasm in the field of research, mainly because of the great benefits they promise in terms of flexibility, cost, range and robustness. In addition, s... Wireless sensor networks are currently experiencing widespread enthusiasm in the field of research, mainly because of the great benefits they promise in terms of flexibility, cost, range and robustness. In addition, such networks find use in a wide variety of applications, for example in collecting remote data, type of climate monitoring, seismic activity, or in other areas such?as home automation and medical. Unfortunately, their disadvantages are up to their promises. Indeed, the sensor nodes are subjected to high energy consumption constraints due to their compact size as well as the deployment environment. Frequent replacement of batteries is excluded in a field that can be difficult to access. Therefore, the main challenge remains as a result of miniaturization and reduces power consumption to maximize network lifetime. The objective of this work is to make a thorough study of the energy consumption in wireless sensor networks. The study points are addressed at the media access protocol or MAC protocol. 展开更多
关键词 WIRELESS Sensor Networks FAULT TOLERANCE mac protocol Suitable for WSN
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A DUAL RESERVATION CDMA-BASED MAC PROTOCOL WITH POWER CONTROL FOR AD HOC NETWORKS
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作者 Jia Min Chen Huimin Yuan Yuhua 《Journal of Electronics(China)》 2007年第1期64-68,共5页
This paper proposes a new multi-channel Medium Access Control (MAC) protocol named as Dual Reservation Code Division Multiple Access (CDMA) based MAC protocol with Power Control (DRCPC). The code channel is divided in... This paper proposes a new multi-channel Medium Access Control (MAC) protocol named as Dual Reservation Code Division Multiple Access (CDMA) based MAC protocol with Power Control (DRCPC). The code channel is divided into common channel,broadcast channel and several data chan-nels. And dynamic power control mechanism is implemented to reduce near-far interference. Compared with IEEE 802.11 Distributed Coordination Function (DCF) protocol,the results show that the pro-posed mechanism improves the average throughput and limits the transmission delay efficiently. 展开更多
关键词 Ad hoc networks Medium Access Control mac protocol MULTICHANNEL Code Division Multiple Access (CDMA) Power control
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Collision Resolution MAC Protocols for Wireless Ad Hoc Networks
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作者 Xinhua Yang Tracy Camp 《Communications and Network》 2013年第1期16-33,共18页
In wireless ad hoc networks, nodes cooperatively form a network without any infrastructure such as a BS/AP (base station or access point). The widely-used contention-based MAC protocol, IEEE 802.11b, is inefficient in... In wireless ad hoc networks, nodes cooperatively form a network without any infrastructure such as a BS/AP (base station or access point). The widely-used contention-based MAC protocol, IEEE 802.11b, is inefficient in multi-hop networks due to the hidden and exposed terminal problems. The most popular schedule-based MAC protocol, TDMA (time division multiple access), is difficult to implement in an ad hoc network due to the lack of infrastructure. The contribution of this paper is to provide the community novel and efficient MAC (medium access control) protocols (i.e., a collision resolution protocol) for a wireless ad hoc network without a centralized infrastructure. We propose two new MAC protocols (one distributed algorithm and one cluster-based algorithm) that use a collision resolution scheme for a network with a single BS/AP. We first compare the performance of our distributed algorithm with our cluster-based algorithm. Then, we compare our algorithm that performs better (i.e., our cluster-based algorithm) to TDMA in a two-hop network. The simulation results illustrate that our cluster-based algorithm provides higher throughput and lower delay than TDMA in a two-hop network. 展开更多
关键词 AD HOC Networks Cluster-Based ALGORITHMS COLLISION RESOLUTION Scheme mac protocols
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Energy Efficient Packet-Duration-Value Based MAC Protocol for Wireless Sensor Networks
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作者 Abayomi M. Ajofoyinbo 《Wireless Sensor Network》 2013年第10期194-202,共9页
Medium Access Control (MAC) protocol consists of sets of rules that determine which node is allowed to access the transmission medium. It provides mechanism for collision avoidance such that interfering sensor nodes d... Medium Access Control (MAC) protocol consists of sets of rules that determine which node is allowed to access the transmission medium. It provides mechanism for collision avoidance such that interfering sensor nodes do not transmit at the same time. In the literature, researchers have proposed different MAC protocols with features aimed at improving energy efficiency and thereby prolonging the life of sensor nodes. Sensor MAC, Time-out MAC (T-MAC), Dynamic Sensor MAC (DSMAC), WiseMAC, Quorum-based MAC (Queen-MAC) and Traffic Adaptive Medium Access Protocol (TRAMA) are some examples of proposed MAC protocols. There is a duration field in each transmitted packet. The value of this field indicates how long it will take to complete the remaining packet transmission. In the current paper, a novel energy-efficient MAC protocol is proposed based on the use of duration value in transmitted packets to setup varying sleep/wake-up schedules for neighbouring nodes of the receiver. The effectiveness of this proposed Packet-Duration-Value-based MAC (PDV-MAC) protocol is tested via Simulation which is implemented in Visual C# and MATLAB. It is shown by the results obtained that the proposed MAC protocol can indeed be implemented in sensor nodes to improve energy efficiency in wireless sensor network. 展开更多
关键词 Wireless Energy Efficient PDV-mac protocol Sensor PACKET DURATION VALUE
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An Energy-Efficient MAC Protocol for Ad Hoc Networks
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作者 Yongsheng SHI T. Aaron GULLIVER 《Wireless Sensor Network》 2009年第5期407-416,共10页
A mobile ad hoc network (MANET) is a collection of nodes equipped with wireless communications and a networking capability without central network control. Nodes in a MANET are free to move and organize themselves in ... A mobile ad hoc network (MANET) is a collection of nodes equipped with wireless communications and a networking capability without central network control. Nodes in a MANET are free to move and organize themselves in an arbitrary fashion. Energy-efficient design is a significant challenge due to the characteristics of MANETs such as distributed control, constantly changing network topology, and mobile users with limited power supply. The IEEE 802.11 MAC protocol includes a power saving mechanism, but it has many limitations. A new energy-efficient MAC protocol (EE-MAC) is proposed in this paper. It is shown that EE-MAC performs better than IEEE 802.11 power saving mode and exceeds IEEE 802.11 with respect to balancing network throughput and energy savings. 展开更多
关键词 ENERGY-EFFICIENT mac protocol IEEE 802.11 Ad HOC Networks
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A Novel DSA-Driven MAC Protocol for Cognitive Radio Networks
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作者 Hua SONG Xiaola LIN 《Wireless Sensor Network》 2009年第2期112-121,共10页
With the deployment of more wireless applications, spectrum scarcity becomes an issue in many countries. Recent reports show that the reason for this spectrum shortage is the underutilization of some spectrum re-sourc... With the deployment of more wireless applications, spectrum scarcity becomes an issue in many countries. Recent reports show that the reason for this spectrum shortage is the underutilization of some spectrum re-sources. Fortunately, the emergence of open spectrum and dynamic spectrum assess (DSA) technology in cognitive radio networks relieves this problem. In this paper, we propose a novel DSA-driven cognitive MAC protocol to achieve highly efficient spectrum usage and QoS provisioning. In the proposed protocol, secondary users are divided into several non-overlapping groups, and all leftover channels are allocated among groups taking the groups’ bandwidth requirements into consideration. Moreover, the allocation of vacant channels can be adjusted dynamically when members join/leave groups or primary users return/leave the current network. Simulations show that the proposed MAC protocol greatly improves the quality of ser-vice for secondary users and maximizes the utilization ratio of spectrum resources. 展开更多
关键词 Cognitive Radio DSA-Driven mac protocol QoS PROVISIONING Dynamic Spectrum Access
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