52,339 research outputs found
Medium Access Control for Wireless Sensor Networks based on Impulse Radio Ultra Wideband
This paper describes a detailed performance evaluation of distributed Medium
Access Control (MAC) protocols for Wireless Sensor Networks based on Impulse
Radio Ultra Wideband (IR-UWB) Physical layer (PHY). Two main classes of Medium
Access Control protocol have been considered: Slotted and UnSlotted with
reliability. The reliability is based on Automatic Repeat ReQuest (ARQ). The
performance evaluation is performed using a complete Wireless Sensor Networks
(WSN) simulator built on the Global Mobile Information System Simulator
(GloMoSim). The optimal operating parameters are first discussed for IR-UWB in
terms of slot size, retransmission delay and the number of retransmission, then
a comparison between IR-UWB and other transmission techniques in terms of
reliability latency and power efficiency
Local Multicoloring Algorithms: Computing a Nearly-Optimal TDMA Schedule in Constant Time
The described multicoloring problem has direct applications in the context of
wireless ad hoc and sensor networks. In order to coordinate the access to the
shared wireless medium, the nodes of such a network need to employ some medium
access control (MAC) protocol. Typical MAC protocols control the access to the
shared channel by time (TDMA), frequency (FDMA), or code division multiple
access (CDMA) schemes. Many channel access schemes assign a fixed set of time
slots, frequencies, or (orthogonal) codes to the nodes of a network such that
nodes that interfere with each other receive disjoint sets of time slots,
frequencies, or code sets. Finding a valid assignment of time slots,
frequencies, or codes hence directly corresponds to computing a multicoloring
of a graph . The scarcity of bandwidth, energy, and computing resources in
ad hoc and sensor networks, as well as the often highly dynamic nature of these
networks require that the multicoloring can be computed based on as little and
as local information as possible
Procedure for Selecting a Transmission Mode Dependent on the State-of-Charge and State-of-Health of a Lithium-ion Battery in Wireless Sensor Networks with Energy Harvesting Devices
Diverse methods and considerations have been proposed to manage the available energy in an efficient manner in Wireless Sensor Networks. By incorporating Energy Harvesting Devices in these type of networks it is possible to reduce the dependency of the availability of the Energy Storage Devices, particularly the lithium-ion battery. Recently, the State-of-Charge and State-of-Health of the battery have been considered as inputs for the design of the Medium- Access-Control protocols for Wireless Sensor Networks. In this article, different guidelines are proposed for the design of Medium-Access-Control protocols used in Wireless Sensor Networks with Energy Harvesting Devices considering the State-of-Charge and State-of-Health as indicators for the estimation of the transmission time of the sensor node. The proposed guidelines consider different currents used during the transmission to estimate the State-of-Charge and Stateof- Health of the battery. The incorporation of these indicators aim to improve the decision-making process of the sensor node when transmitting.Diverse methods and considerations have been proposed to manage the available energy in an efficient manner in Wireless Sensor Networks. By incorporating Energy Harvesting Devices in these type of networks it is possible to reduce the dependency of the availability of the Energy Storage Devices, particularly the lithium-ion battery. Recently, the State-of-Charge and State-of-Health of the battery have been considered as inputs for the design of the Medium- Access-Control protocols for Wireless Sensor Networks. In this article, different guidelines are proposed for the design of Medium-Access-Control protocols used in Wireless Sensor Networks with Energy Harvesting Devices considering the State-of-Charge and State-of-Health as indicators for the estimation of the transmission time of the sensor node. The proposed guidelines consider different currents used during the transmission to estimate the State-of-Charge and Stateof- Health of the battery. The incorporation of these indicators aim to improve the decision-making process of the sensor node when transmitting
Channel Sharing based Medium Access Control Protocol for Wireless Nano Sensing Network
Recent advancement and grown up technologies has enabled the development and implementation of low-cost, energy efficient and versatile sensor networks. Sensor networks are built up with sensors that have the ability to sense physical or environmental property. Assumption can be made that Wireless Sensing Network (WSN) is able to sense environmental conditions at Nano and gaseous level. This architecture of Wireless Sensor Network is maintained by a sub-layer named Medium Access Control Layer that provides addressing and channel access control mechanism among multiple nodes of the network and makes these nodes capable to communicate with other nodes through a shared medium. The hardware that implements the MAC is referred to as a medium access controller. This paper finds the problems in selection of cluster nodes and transmitting data and also proposes an improved MAC protocol to minimize the problem
Novel Medium Access Control (MAC) Protocols for Wireless Sensor and Ad Hoc Networks (WSANs) and Vehicular Ad Hoc Networks (VANETs)
Efficient medium access control (MAC) is a key part of any wireless network communication architecture. MAC protocols are needed for nodes to access the shared wireless medium efficiently. Providing high throughput is one of the primary goals of the MAC protocols designed for wireless networks. MAC protocols for Wireless Sensor and Ad hoc networks (WSANs) must also conserve energy as sensor nodes have limited battery power. On the other hand, MAC protocols for Vehicular Ad hoc networks (VANETs) must also adapt to the highly dynamic nature of the network. As communication link failure is very common in VANETs because of the fast movement of vehicles so quick reservation of packet transmission slots by vehicles is important.
In this thesis we propose two new distributed MAC algorithms. One is for WSANs and the other one is for VANETs. We demonstrate using simulations that our algorithms outperform the state-of-the-art algorithms
Collaborative communication protocols for wireless sensor networks
In this document, the design of communication within a wireless sensor network is discussed. The resource limitations of such a network, especially in terms of energy, require an integrated approach for all (traditional) layers of communication. We present such an integrated, collaborative approach which is part of current research in the European research project EYES on energy-efficient sensor networks. In particular, energy-efficient solutions for medium access control, clusterbased routing and multipath routing are discussed. As part of the ongoing project, these approaches work together and are designed to support each other
H-MAC: A Hybrid MAC Protocol for Wireless Sensor Networks
In this paper, we propose a hybrid medium access control protocol (H-MAC) for
wireless sensor networks. It is based on the IEEE 802.11's power saving
mechanism (PSM) and slotted aloha, and utilizes multiple slots dynamically to
improve performance. Existing MAC protocols for sensor networks reduce energy
consumptions by introducing variation in an active/sleep mechanism. But they
may not provide energy efficiency in varying traffic conditions as well as they
did not address Quality of Service (QoS) issues. H-MAC, the propose MAC
protocol maintains energy efficiency as well as QoS issues like latency,
throughput, and channel utilization. Our numerical results show that H-MAC has
significant improvements in QoS parameters than the existing MAC protocols for
sensor networks while consuming comparable amount of energy.Comment: 10 pages, IJCNC Journal 201
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