一种低时延的无线传感器网络MAC协议

简要分析了无线传感器网络MAC层协议的作用,针对MAC协议在低时延方面的不足,提出了一种低时延的MAC协议(L-MAC).该协议采用汇聚树,在满足低功耗的基础上,减少了时延.理论分析和仿真实验表明L-MAC较好地解决了时延问题.     

一种高效节能的无线传感器网络 MAC 协议

针对无线传感器网络 MAC 协议的作用与要求,给出一种基于 CDMA 的 MAC 协议改进方案.根据网络负载变化采用周期性的侦听/睡眠机制,使大多数节点处于睡眠状态,节省能耗;同时结合 CDMA 技术给节点分配网内唯一的具有正交性的高速伪随机码(PN)来调制数据信号,使之在时域和频域重叠,实现数据的大规模实时传送.仿真结果表明,协议在保证系统低延时和高吞吐量的同时,能明显减少能量消耗.     

一种基于路由信息能量有效的无线传感器网MAC协议

传感器节点沿树状多跳路径逐级向Sink转发数据是无线传感器网络的主要业务模式之一。针对此类业务,该文的EBRI-MAC(Energy-efficient MAC protocol Based on Routing Information)协议提出一种对应树状路由转发关系,由父节点与子节点构成虚拟群的思想;并设计了连锁邀请与CSMA/CA结合的信道接入机制以及基于虚拟群同步的周期休眠机制,以达到节能的目的。结合节点能耗因素,定义了能量有效性的性能参数,并对EBRI-MAC的能量有效性进行理论分析。通过ns-2仿真结果表明网络业务时间相关性较强时,EBRI-MAC的能量有效性优于IEEE802.11DCF和S-MAC。     

一种基于服务质量的节能无线传感器网络MAC协议

为了平衡网络能耗与QoS,提出了一种基于服务质量的节能MAC协议-QE-MAC.该协议一方面采用由Hill等人提出的低能量载波侦听技术降低节点能耗,另一方面,采用冲突避免、回复确认、区分优先级和失败重传等机制确保分组传输的可靠性,以及使用业务固定短周期发起策略来解决分组接收的时延过大问题.模拟实验和测试结果都表明,QE-MAC能够以较低的网络能耗提供良好的QoS.     

无线传感器网络中一种动态节能的MAC协议

媒体访问控制(MAC)协议是无线传感器网络的关键协议之一,它对无线传感网络的运行和性能具有重要的影响.针对基于簇的TDMA机制存在问题,文中提出了一个动态节能的DE-MAC协议,该协议能够根据簇成员节点数目和通信负载动态地分配成员节点的时隙,减少节点的空闲侦听时间.仿真结果表明,DE-MAC协议能够有效地提高信道的利用率和网络能量有效性.     

无线传感器网络高效的MAC协议研究

目前无线传感器网络中的MAC协议可分为发送端启动和接收端启动两类.同步的发送端启动协议同步代价高,基于前导的异步协议网络利用率低,而接收端启动的算法会产生发送端盲等等问题.本文结合这两类协议的优点,提出一种可自适应变换数据传输模式的MAC协议(IL-MAC).该协议根据节点的消息队列长度决定当前使用哪种传输模式,并通过...     

一种自适应侦听的异步无线传感器网络MAC协议

为了提升异步无线传感器网络MAC协议在动态网络负载下的性能,论文提出了一种流量自适应的异步协议AA-MAC.该协议基于短前导序列采样技术,当节点收稿数据后并不理解转入睡眠而自适应增加若干个最短侦听时间用以接收发送节点的可能其他数据,使得收发双方在网络负载较重时能实现一次配对多次收发数据.分析并对比了AA-MAC和X-M...     

Adaptive MAC Protocol for Solar Energy Harvesting Based Wireless Sensor Networks in Agriculture

The wireless sensor network is one of the promising technologies in the agriculture field. Its actual usage in real agriculture fields is limited by its dependence on the small batteries which cannot make the network survive for long. Various protocols are being designed at the network and MAC layer to increase the lifetime of the nodes, but up to a certain extent only. Hence the energy harvesting to power up the WSN nodes is a promising technology to fulfill this ever energy demand, but the protocols need to be redesigned for this scenario. Solar energy harvesting based MAC protocol which is adaptive to the changing weather conditions is designed in this paper for the smart agriculture applications. It is based on the multilayer and receiver-initiated process to improve network quality. It has shown the remarkable performance over the other energy harvesting based protocols in terms of ENO ratio, energy consumption and collision rate.

     

An Energy Conservation MAC Protocol in Wireless Sensor Networks

Wireless sensor networks use battery-operated computing and sensing devices. Because of the limitation of battery power in the sensor nodes, energy conservation is a crucial issue in wireless sensor networks. Consequently, there is much literature presenting energy-efficient MAC protocols based on active/sleep duty cycle mechanisms to conserve energy. Convergecast is a common communication pattern across many sensor network applications featuring data gathering from many different source nodes to a single sink node. This leads to high data collision rates, high energy consumption, and low throughput near the sink node. This paper proposes an efficient slot reservation MAC protocol to reduce energy consumption and to make transmission more efficient in data gathering wireless sensor networks. The simulation results show that our protocol provides high throughput, low delivery latency and low energy consumption compared to other methods.

Local Group Communication-aware MAC Protocol in Wireless Sensor Networks

In this paper, we investigate the problem of providing efficient communication primitives across domains of wireless sensor network (WSN) applications. We argue both qualitatively and quantitatively that group communication among sensors of geographic proximity is one of the basic building blocks of many WSN applications. Furthermore, group communication awareness needs to be embedded and implemented at the MAC layer due to the broadcast nature of wireless medium. We devise a MAC protocol, called LGC-MAC to enable efficient single-hop one-to-many and many-to-one communication. We present case studies of two example applications, acoustic target tracking and propagation of information with feedback using LGC-MAC and demonstrate that LGC-MAC can improve the response time, alleviate channel contention and provide better fault tolerance to packet collisions and wireless errors.

SyncWUF: An Ultra Low-Power MAC Protocol for Wireless Sensor Networks

In wireless sensor networks, power consumption is one of the key design issues because a large number of sensor nodes are powered by cheap batteries. Switching the RF transceiver, which is one of the biggest power consumers in a sensor node, to low-power sleep mode as much as possible has been proven to be a very efficient way to save power with a factor of tens or even hundreds. So far, several schemes have been proposed to reduce the duty cycle of the RF transceiver by MAC layer scheduling. Among them, the wake-up-frame scheme and the WiseMAC are two very efficient protocols based on the so-called preamble sampling technology. This paper proposes combining these two schemes to obtain a further optimized low-power MAC protocol, called SyncWUF, for low-traffic wireless sensor network. Analytical and simulation results prove that our proposal achieves significant battery lifetime gain in different application cases without negatively affecting other important system parameters such as channel capacity and latency     

An Application Oriented Power Saving MAC Protocol for Wireless Sensor Networks

Energy efficiency has been an important concern in wireless sensor networks where Medium Access Control (MAC) protocol plays an important role. However, current MAC protocols designed for energy saving have seldom considered multiple applications coexisting in WSN with variation of traffic load dynamics. In this paper, we propose an adaptive control algorithm at MAC layer to promote energy efficiency. We focus on the tradeoff relation between collisions and control overhead as a reflection of traffic load and propose to balance the tradeoff under the constraints of QoS options. We integrate the algorithm into S-MAC and verify it through NS-2 platform. The simulation results demonstrate that our algorithm achieves observable improvement in energy performance while meeting QoS requirement for different coexisting applications in comparison with S-MAC.     

A Low Duty Cycle MAC Protocol for Directional Wireless Sensor Networks

Directional communication in wireless sensor networks minimizes interference and thereby increases reliability and throughput of the network. Hence, directional wireless sensor networks (DWSNs) are fastly attracting the interests of researchers and industry experts around the globe. However, in DWSNs the conventional medium access control protocols face some new challenges including the synchronization among the nodes, directional hidden terminal and deafness problems, etc. For taking the advantages of spatial reusability and increased coverage from directional communications, a low duty cycle directional Medium Access control protocol for mobility based DWSNs, termed as DCD-MAC, is developed in this paper. To reduce energy consumption due to idle listening, duty cycling is extensively used in WSNs. In DCD-MAC, each pair of parent and child sensor nodes performs synchronization with each other before data communication. The nodes in the network schedule their time of data transmissions in such a way that the number of collisions occurred during transmissions from multiple nodes is minimized. The sensor nodes are kept active only when the nodes need to communicate with each other. The DCD-MAC exploits localized information of mobile nodes in a distributed manner and thus it gives weighted fair access of transmission slots to the nodes. As a final point, we have studied the performance of our proposed protocol through extensive simulations in NS-3 and the results show that the DCD-MAC gives better reliability, throughput, end-to-end delay, network lifetime and overhead comparing to the related directional MAC protocols.     

Energy‐Efficient Quorum‐Based MAC Protocol for Wireless Sensor Networks

The reliability of sensor networks is generally dependent on the battery power of the sensor nodes that it employs; hence it is crucial for the sensor nodes to efficiently use their battery resources. This research paper presents a method to increase the reliability of sensor nodes by constructing a connected dominating tree (CDT), which is a subnetwork of wireless sensor networks. It detects the minimum number of dominatees, dominators, forwarder sensor nodes, and aggregates, as well as transmitting data to the sink. A new medium access control (MAC) protocol, called Homogenous Quorum‐Based Medium Access Control (HQMAC), is also introduced, which is an adaptive, homogenous, asynchronous quorum‐based MAC protocol. In this protocol, certain sensor nodes belonging to a network will be allowed to tune their wake‐up and sleep intervals, based on their own traffic load. A new quorum system, named BiQuorum, is used by HQMAC to provide a low duty cycle, low network sensibility, and a high number of rendezvous points when compared with other quorum systems such as grid and dygrid. Both the theoretical results and the simulation results proved that the proposed HQMAC (when applied to a CDT) facilitates low transmission latency, high delivery ratio, and low energy consumption, thus extending the lifetime of the network it serves.     

一种自适应调整发送概率的无线传感器网络MAC协议

文章提出一种新的无线传感器网络MAC协议AMAC.AMAC是对S-MAC的扩展,克服了S-MAC采用固定竞争窗,无法适应网络负载变化的缺点.为不影响协议休眠激活周期的建立,文章提出固定竞争窗加p坚持的退避算法,当退避计数器减为零时,节点不是立即发送数据,而是以最优概率p发送.为确定p值,又推导出使平均发送能耗最小的p与活动节点数的关系,同时提出了活动节点数估计算法.最后通过仿真验证了AMAC协议的自适应性和能量有效性.     

An Energy-Efficient and Collision-Avoidance MAC Protocol with Pre-scheduling for Wireless Sensor Networks

In this paper, we propose energy efficient MAC protocols for data gathering tree structure. The basic concept of the proposed protocol is that it reduces traffic overloads in low depth nodes by introducing full sleep state for one frame. To maximize network performance, we only control traffic from non-relay nodes which are leaf nodes in the tree. We introduce a new superframe structure for pre-scheduling to alleviate contentions and packet collisions between children nodes. In addition, leaf nodes go into a full sleep mode for one superframe in heavy traffic loads by using control packets, which results in a considerable reduction of energy consumption at low depth nodes. Simulation results show the proposed protocol saves more energy and achieves better packet delivery ratio compared to the DMAC with a moderate increase of a latency performance.     

Delay-Aware MAC Protocol for Wireless Sensor and Actor Networks in Smart Grid

Wireless Personal Communications - The conventional electric grid is converting in to the new emerging smart grid by utilizing information and communication technologies. The smart grid...     

An Energy-Efficient Self-Adaptive Duty Cycle MAC Protocol for Traffic-Dynamic Wireless Sensor Networks

A plenty of Medium Access Control (MAC) protocols deal with static traffics with low traffic load. The performance of these protocols drops significantly when network traffic become dynamic or in high traffic load. In this paper, we propose a new MAC protocol called Self-Adaptive Duty Cycle MAC (SEA-MAC) by introducing dual adaptive mechanisms: (1) An Adaptive Scheduling (AS) mechanism which makes the nodes’ active duration adaptive to variable traffic load, thus enabling SEA-MAC to resiliently schedule data transmission for the Sleep period. The algorithm is designated to schedule more data transmission in bursty and high traffic load, thus enabling rapid dissemination of data and reduction of latency. While under the light traffic load, nodes enter the Sleep mode timely, mitigating idle listening and saving energy. (2) A Self-Adaptive duty cycle mechanism which further adjusts the duty cycle and makes SEA-MAC adaptive to the dynamic traffic loads. When network experience with very low or very high traffic load, the protocol further adjusts duty cycle dynamically based on the traffic load, thus reducing inefficient duty cycle or reduce end-to-end delay. Experiment results show that the SEA-MAC is a great advancement compared with AS-MAC and RI-MAC protocols on the performance for unicast scenarios, especially under heavy unicast traffic load. SEA-MAC can reduce average and max end-to-end delay up to 50.90 and 68.20% respectively, lower energy consumption up to about 16.28%, and increase PDR up to about 16% compared with AS-MAC. SEA-MAC superiors to RI-MAC in average end-to-end delay by up to 80% and in maximum end-to-end delay up to 90% for all the traffic load in question. SEA-MAC outperforms RI-MAC significantly in average duty cycle under medium and heavy traffic load.     

Low-Energy Adaptive Unequal Clustering Protocol Using Fuzzy c-Means in Wireless Sensor Networks

Clustering technique in wireless sensor networks incorporate proper utilization of the limited energy resources of the deployed sensor nodes with the highest residual energy that can be used to gather data and send the information. However, the problem of unbalanced energy consumption exists in a particular cluster node in the network. Some more powerful nodes act as cluster head to control sensor network operation when the network is organized into heterogeneous clusters. It is important to assume that energy consumption of these cluster head nodes is balanced. Often the network is organized into clusters of equal size where cluster head nodes bear unequal loads. Instead in this paper, we proposed a new protocol low-energy adaptive unequal clustering protocol using Fuzzy c-means in wireless sensor networks (LAUCF), an unequal clustering size model for the organization of network based on Fuzzy c-means (FCM) clustering algorithm, which can lead to more uniform energy dissipation among the cluster head nodes, thus increasing network lifetime. A heuristic comparison between our proposed protocol LAUCF and other different energy-aware protocol including low energy adaptive clustering hierarchy (LEACH) has been carried out. Simulation result shows that our proposed heterogeneous clustering approach using FCM protocol is more effective in prolonging the network lifetime compared with LEACH and other protocol for long run.     

一种基于休眠调度策略的无线传感网络分簇协议

文中设计了一种基于休眠调度策略的无线传感网络分簇协议.该协议计算出簇首最佳比例和网络瞬时剩余能量,采用固定簇首数目与剩余能量估计的方法对网络进行分簇,在成簇后的数据传送阶段采用蚁群算法计算出节点的唤醒概率,最后通过仿真实验与LEACH、SEP协议进行了比较.实验结果表明:该协议在对目标保持较好探测效果的前提下能更均匀的消耗网络的能量,从而延长网络的生命周期.