Download or read book A SINR Based MAC Layer Protocol for Multi channel Ad hoc Networks written by Imran Haider Gulam Haider Balsania and published by . This book was released on 2010 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: A SINR based MAC layer protocol for multi-channel ad-hoc networks is proposed. The protocol provides a distributed solution to a node pair that has to choose the "best" channel amongst the available 'M' channels (M>1). We define "best channel selection" in terms of the least interference power measurement encountered on a particular channel by the receiving station throughout the entire duration of data exchange. Using Medium Access Control (MAC) layer mechanisms for message exchange between the nodes, our algorithm achieves not only interference mitigation but also solves the classical hidden and exposed terminal problems in wireless networks. Simulations performed on the NS-2 platform validate the throughput gain achieved by our algorithm in comparison to IEEE 802.11 MAC scheme alongside two other state-of-the-art multichannel MAC protocols.
Download or read book A Multi channel MAC Layer Protocol with Dynamic Bandwidth Allocation for Ad Hoc Networks written by Manasi Velhankar and published by . This book was released on 2007 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Composite Metric Based Multi channel MAC Protocol for Ad hoc Network written by Yogita Mehta and published by . This book was released on 2005 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: [Author's abstract] Recent technology advances have opened a new spectrum of communication networks called ad hoc networks. In an ad hoc network, the Media Access Control (MAC) protocol of IEEE 802.11 Distributed Coordination Function (DCF), designed to share a single channel between nodes. This thesis presents a protocol that facilitates use of more than one channel and analytical analysis for the throughput of the network. One of the functions of a MAC layer is to scan all channels. A composite metric (CM) has been proposed for each available channel. The CM depends on the signal to noise ratio, the battery power remaining and the mobility of each node with respect to other nodes in the network. The channels with three higher CMs are selected at each node and are used to build a Preferred Channel List (PCL). During Announcement Traffic Indication Message (ATIM), the PCL is sent by the node intended to communicate with another node. If the PCL of the receiver node has non interfering channels with the PCL of the sender node, it responds with an ATIM ACK with its PCL. If the PCL of both nodes have appropriate channels, then the sender node replies with an ATIM RES indicating that at the end of the ATIM window, the RTS/CTS/DATA/ACK handshake will begin. A mathematical model based on Markov chain process is designed to derive an expression for saturation throughput and evaluate the performance of Composite Metric (CM) based Multi channel MAC (MMAC) against IEEE 802.11 MAC Distributed Co ordination Function (DCF) and Dynamic Channel Allocation (DCA) protocol. IEEE 802.11 MAC, DCA and CM based MMAC protocol works better for large data packets than for small data packets. Simulation results show enhancement of 35 to 95 percent in the overall throughput of the network when the proposed CM based MMAC protocol used over IEEE 802.11 MAC and DCA protocols.
Download or read book Cooperative Multi channel MAC Protocols for Wireless Ad Hoc Networks written by Yuhan Moon and published by . This book was released on 2010 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: Today, many wireless networks are single-channel systems. However, as the interest in wireless services increases, the contention by nodes to occupy the medium is more intense and interference worsens. One direction with the potential to increase system throughput is multi-channel systems. Multi-channel systems have been shown to reduce collisions and increase concurrency thus producing better bandwidth usage. However, the well-known hidden- and exposed-terminal problems inherited from single-channel systems remain, and a new channel selection problem is introduced. In this dissertation, Multi-channel medium access control (MAC) protocols are proposed for mobile ad hoc networks (MANETs) for nodes equipped with a single half-duplex transceiver, using more sophisticated physical layer technologies. These include code division multiple access (CDMA), orthogonal frequency division multiple access (OFDMA), and diversity. CDMA increases channel reuse, while OFDMA enables communication by multiple users in parallel. There is a challenge to using each technology in MANETs, where there is no fixed infrastructure or centralized control. CDMA suffers from the near-far problem, while OFDMA requires channel synchronization to decode the signal. As a result CDMA and OFDMA are not yet widely used. Cooperative (diversity) mechanisms provide vital information to facilitate communication set-up between source-destination node pairs and help overcome limitations of physical layer technologies in MANETs. In this dissertation, the Cooperative CDMA-based Multi-channel MAC (CCM-MAC) protocol uses CDMA to enable concurrent transmissions on each channel. The Power-controlled CDMA-based Multi-channel MAC (PCC-MAC) protocol uses transmission power control at each node and mitigates collisions of control packets on the control channel by using different sizes of the spreading factor to have different processing gains for the control signals. The Cooperative Dual-access Multi-channel MAC (CDM-MAC) protocol combines the use of OFDMA and CDMA and minimizes channel interference by a resolvable balanced incomplete block design (BIBD). In each protocol, cooperating nodes help reduce the incidence of the multi-channel hidden- and exposed-terminal and help address the near-far problem of CDMA by supplying information. Simulation results show that each of the proposed protocols achieve significantly better system performance when compared to IEEE 802.11, other multi-channel protocols, and another protocol CDMA-based.
Download or read book Medium Access Control Protocols for Multi hop Wireless Ad Hoc Networks written by Venkatesh Rajendran and published by . This book was released on 2006 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Control channel Reuse based Multi channel MAC Protocol for Ad Hoc Networks written by Divya Sardana and published by . This book was released on 2009 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ad hoc networks have become a popular type of wireless network in the present world. In order to match with the increasing demand of ad hoc networks, a lot of research is being done towards solving the issues related to the design of ad hoc networks. The design of a Medium Access Control (MAC) protocol for ad hoc networks is one such issue. Traditional MAC protocols involve the use of a single channel as the wireless medium. However, throughput of a single channel MAC degrades as the node traffic in the system increases. One of the interesting approaches towards alleviating this problem is the use of more than one channel as the underlying medium. The use of multiple channels allows more than one communication to take place simultaneously thereby improving the throughput of the system. Multiple channels have been mostly used in the literature by assigning one of the channels as the control channel used only for control packet transfer and the rest of the channels as data channels used for Data packet transfer. Using such an approach towards designing a multi-channel MAC protocol leads to a poor utilization of the available bandwidth. In this thesis, we propose a multi-channel MAC protocol called as Control-channel Reuse based Multi-channel MAC (CRM-MAC) which aims at improving the overall bandwidth utilization. We illustrate the efficacy of our protocol through elaborate simulations.
Download or read book Sender and Receiver initiated Multiple Access Protocols for Ad hoc Networks written by Asimakis E. Tzamaloukas and published by . This book was released on 2000 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on the medium access control (MAC) layer. Many MAC protocols for wireless networks proposed or implemented to date are based on collision-avoidance handshakes between sender and receiver. The key objective of collision-avoidance handshakes is reducing or eliminating the collision of data packets from a source at any given receiver due to interference from packets from other sources. In the vast majority of these protocols, including the IEEE 802.11 standard, the handshake is sender-initiated, in that the sender asks the receiver for permission to transmit using a short control packet, and transmits only after the receiver sends a short clear-to-send notification. There are two main objectives in this work: analyze the effect of reversing the collision-avoidance handshake as a way to improve the performance of MAC protocols under any conditions in the network, and design MAC protocols that provide correct floor acquisition without carrier sensing or code pre-assignment. We show that receiver-initiated collision-avoidance MAC protocols not only outperform any sender-initiated ones, but also guarantee collision-free data transmission and seamless support for mobility by using simple, low-cost wireless radios. We study the effect of persistent carrier sensing in receiver- as well as sender-initiated MAC protocols. We extend our work to multi-channel radios and introduce novel collision-avoidance MAC protocols that eliminate the need for carrier sensing and code pre-assignment, and improve the utilization of the medium in the presence of unicast, multicast and broadcast traffic.
Download or read book Multichannel Medium Access Control Protocol with Cooperative Channel Selection for Ad Hoc Networks written by Jai Mondhe and published by . This book was released on 2003 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: A mobile ad hoc network is a collection of mobile terminals equipped with wireless transceivers that form an autonomous network without any pre-planned infrastructure or centralized administration. Wireless hosts in an ad hoc network typically share a single common channel for communication. The Medium Access Control (MAC) allows the hosts to resolve contention while randomly accessing the channel and plays a key role in determining the efficiency of channel usage in the network. Usage of multiple channels improves the throughput of the MAC protocol in ad hoc networks by allowing multiple nodes to transmit concurrently on different non-overlapping channels. Efficient channel selection schemes can reduce the contention in each channel leading to smaller number of collisions, backoffs, and retransmissions. This research explores a new channel selection scheme that is based on maximizing the signal to interference ratio at the receiver as well as minimizing the interference caused to all other active receivers in the vicinity of the sender. An implementation of this "cooperative" channel selection technique is proposed employing receiver-initiated busy-tones and signal power measurements at the sending and receiving nodes respectively. Simulation based performance results are presented.
Download or read book Wireless Ad Hoc and Sensor Networks written by Raja Jurdak and published by Springer Science & Business Media. This book was released on 2007-04-27 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the optimization potential of cross-layer design approaches for wireless ad hoc and sensor network performance, covering both theory and practice. A theoretical section provides an overview of design issues in both strictly layered and cross-layer approaches. A practical section builds on these issues to explore three case studies of diverse ad hoc and sensor network applications and communication technologies.
Download or read book Multi channel MAC Protocols for Wireless Ad Hoc Networks written by Mehdi Ait Tahar and published by . This book was released on 2003 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A New Multichannel MAC Protocol for Ad Hoc Networks Based on Two phase Coding with Power Control TPCPC written by and published by . This book was released on with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents a new CDMA-based multichannel medium access control protocol for ad hoc networks, which is named as two-phase coding multichannel protocol with power control. The first phase code is used to broaden the area reuse and the second phase code is employed to distinguish between different nodes in one specific area. This algorithm efficiently eliminates hidden terminal and exposed terminal problems during data transmission and greatly increases the throughput. In addition, it has good scalability and can be easily accomplished with GPS. Although many multichannel MAC protocols adopting CDMA techniques have been presented, few have addressed the near-far problem. We incorporate power control in our algorithm and reduce the near-far interference. The implementation of two-phase coding with power control is discussed, and the primary simulation result demonstrates that the proposed protocol offers better performance.
Download or read book Throughput Analysis and Enhancement of Multi Channel MAC Protocol in Ad Hoc Networks written by 高譓翔 and published by . This book was released on 2006 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cross layer Channel Allocation Algorithms for Wireless Ad Hoc Networks written by Marzieh Veyseh and published by . This book was released on 2011 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multi channel Mac Protocols with Bandwidth Utilization Enhancement in Wireless Ad Hoc Networks written by Yun-Jung Lu and published by . This book was released on 2012 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook on Advancements in Smart Antenna Technologies for Wireless Networks written by Sun, Chen and published by IGI Global. This book was released on 2008-07-31 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides information on smart antenna technologies featuring contributions with in-depth descriptions of terminologies, concepts, methods, and applications related to smart antennas in various wireless systems.
Download or read book 3M written by and published by . This book was released on 2014 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Designing for Network and Service Continuity in Wireless Mesh Networks written by Parth H. Pathak and published by Springer Science & Business Media. This book was released on 2012-11-02 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: “Designing for Network and Service Continuity in Wireless Mesh Networks” describes performance predictability of the new wireless mesh network paradigm, and describes considerations in designing networks from the perspective of survivability and service continuity metrics. The work provides design insights for network design researchers and industry professionals. It includes designs for new mesh networks and extensions of existing networks with predictable performance.
