The Experts below are selected from a list of 0 Experts worldwide ranked by ideXlab platform
John Murphy - One of the best experts on this subject based on the ideXlab platform.
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GLOBECOM - System-Level Performance Evaluation of Multi-Cell Transparent Mode Relay 802.16j Systems
GLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John Murphy, Abdelhamid NafaaAbstract:In this paper, the system capacity of a multi-cell IEEE 802.16j system operating in Transparent Mode is investigated. A previous published analytical Model is used and incorporates interference from neighbouring cells. The Model can be used to determine downlink performance under max-min fairness constraints for both sectored and omnidirectional systems with different amounts of relays. The study provides guidelines on the design of 802.16j systems operating in Transparent Mode - specifically, how to maximise throughput for such systems. It is shown that inter-cell interference from relays is limited in a suburban environment and that relays can deliver significant gains over single hop systems: gains of 30% and 60% can be achieved without and with spatial reuse in an omnidirectional system while 15% and 25% in a sectorised system.
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system level performance evaluation of multi cell Transparent Mode relay 802 16j systems
Global Communications Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John Murphy, Abdelhamid NafaaAbstract:In this paper, the system capacity of a multi-cell IEEE 802.16j system operating in Transparent Mode is investigated. A previous published analytical Model is used and incorporates interference from neighbouring cells. The Model can be used to determine downlink performance under max-min fairness constraints for both sectored and omnidirectional systems with different amounts of relays. The study provides guidelines on the design of 802.16j systems operating in Transparent Mode - specifically, how to maximise throughput for such systems. It is shown that inter-cell interference from relays is limited in a suburban environment and that relays can deliver significant gains over single hop systems: gains of 30% and 60% can be achieved without and with spatial reuse in an omnidirectional system while 15% and 25% in a sectorised system.
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WCNC - Analysis of Transparent Mode IEEE 802.16j System Performance with Varying Numbers of Relays and Associated Transmit Power
2009 IEEE Wireless Communications and Networking Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John MurphyAbstract:In this paper, the system capacity of IEEE 802.16j systems operating in Transparent Mode is investigated under varying numbers of relays and associated transmit power. The study is based on an extended variant of an analytical Model defined in previous work and used to determine the throughput gain that can be achieved under a max-min fairness constraint. The study finds that significant overall throughput gains can be achieved over 802.16e systems: 125% and 55% gain with and without spatial reuse, respectively. However, the overall throughput gain drops as the transmit power at the relays (RSs) decreases despite the fact that a greater number of concurrent transmissions can be achieved due to less interference among the RSs' transmissions. Decreasing the transmit power at the RSs eventually leads to a significant reduction of the achievable throughput gain even though a large number of RSs are deployed in scenarios with or without spatial reuse.
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analysis of Transparent Mode ieee 802 16j system performance with varying numbers of relays and associated transmit power
Wireless Communications and Networking Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John MurphyAbstract:In this paper, the system capacity of IEEE 802.16j systems operating in Transparent Mode is investigated under varying numbers of relays and associated transmit power. The study is based on an extended variant of an analytical Model defined in previous work and used to determine the throughput gain that can be achieved under a max-min fairness constraint. The study finds that significant overall throughput gains can be achieved over 802.16e systems: 125% and 55% gain with and without spatial reuse, respectively. However, the overall throughput gain drops as the transmit power at the relays (RSs) decreases despite the fact that a greater number of concurrent transmissions can be achieved due to less interference among the RSs' transmissions. Decreasing the transmit power at the RSs eventually leads to a significant reduction of the achievable throughput gain even though a large number of RSs are deployed in scenarios with or without spatial reuse.
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An Interference-Aware Analytical Model for Performance Analysis of Transparent Mode 802.16j Systems
2008 IEEE Globecom Workshops, 2008Co-Authors: Vasken Genc, Sean Murphy, John MurphyAbstract:In this paper, an interference-aware analytical Model of IEEE 802.16j systems operating in Transparent Mode is described. The Model can be used to determine the throughput gain that can be achieved by 802.16J relay- based systems under a max-min fairness constraint in which the difference between the data rate delivered to all subscribers is minimized. Two variants of the Model are considered - one in which there is no spatial reuse and one in which there is spatial reuse. The study finds that this variant of 802.16j system can deliver significant gains over traditional single-hop access systems: 40% in the case in which there is no spatial reuse and up to 80% when spatial reuse is realised.
Vasken Genc - One of the best experts on this subject based on the ideXlab platform.
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GLOBECOM - System-Level Performance Evaluation of Multi-Cell Transparent Mode Relay 802.16j Systems
GLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John Murphy, Abdelhamid NafaaAbstract:In this paper, the system capacity of a multi-cell IEEE 802.16j system operating in Transparent Mode is investigated. A previous published analytical Model is used and incorporates interference from neighbouring cells. The Model can be used to determine downlink performance under max-min fairness constraints for both sectored and omnidirectional systems with different amounts of relays. The study provides guidelines on the design of 802.16j systems operating in Transparent Mode - specifically, how to maximise throughput for such systems. It is shown that inter-cell interference from relays is limited in a suburban environment and that relays can deliver significant gains over single hop systems: gains of 30% and 60% can be achieved without and with spatial reuse in an omnidirectional system while 15% and 25% in a sectorised system.
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system level performance evaluation of multi cell Transparent Mode relay 802 16j systems
Global Communications Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John Murphy, Abdelhamid NafaaAbstract:In this paper, the system capacity of a multi-cell IEEE 802.16j system operating in Transparent Mode is investigated. A previous published analytical Model is used and incorporates interference from neighbouring cells. The Model can be used to determine downlink performance under max-min fairness constraints for both sectored and omnidirectional systems with different amounts of relays. The study provides guidelines on the design of 802.16j systems operating in Transparent Mode - specifically, how to maximise throughput for such systems. It is shown that inter-cell interference from relays is limited in a suburban environment and that relays can deliver significant gains over single hop systems: gains of 30% and 60% can be achieved without and with spatial reuse in an omnidirectional system while 15% and 25% in a sectorised system.
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WCNC - Analysis of Transparent Mode IEEE 802.16j System Performance with Varying Numbers of Relays and Associated Transmit Power
2009 IEEE Wireless Communications and Networking Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John MurphyAbstract:In this paper, the system capacity of IEEE 802.16j systems operating in Transparent Mode is investigated under varying numbers of relays and associated transmit power. The study is based on an extended variant of an analytical Model defined in previous work and used to determine the throughput gain that can be achieved under a max-min fairness constraint. The study finds that significant overall throughput gains can be achieved over 802.16e systems: 125% and 55% gain with and without spatial reuse, respectively. However, the overall throughput gain drops as the transmit power at the relays (RSs) decreases despite the fact that a greater number of concurrent transmissions can be achieved due to less interference among the RSs' transmissions. Decreasing the transmit power at the RSs eventually leads to a significant reduction of the achievable throughput gain even though a large number of RSs are deployed in scenarios with or without spatial reuse.
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analysis of Transparent Mode ieee 802 16j system performance with varying numbers of relays and associated transmit power
Wireless Communications and Networking Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John MurphyAbstract:In this paper, the system capacity of IEEE 802.16j systems operating in Transparent Mode is investigated under varying numbers of relays and associated transmit power. The study is based on an extended variant of an analytical Model defined in previous work and used to determine the throughput gain that can be achieved under a max-min fairness constraint. The study finds that significant overall throughput gains can be achieved over 802.16e systems: 125% and 55% gain with and without spatial reuse, respectively. However, the overall throughput gain drops as the transmit power at the relays (RSs) decreases despite the fact that a greater number of concurrent transmissions can be achieved due to less interference among the RSs' transmissions. Decreasing the transmit power at the RSs eventually leads to a significant reduction of the achievable throughput gain even though a large number of RSs are deployed in scenarios with or without spatial reuse.
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An Interference-Aware Analytical Model for Performance Analysis of Transparent Mode 802.16j Systems
2008 IEEE Globecom Workshops, 2008Co-Authors: Vasken Genc, Sean Murphy, John MurphyAbstract:In this paper, an interference-aware analytical Model of IEEE 802.16j systems operating in Transparent Mode is described. The Model can be used to determine the throughput gain that can be achieved by 802.16J relay- based systems under a max-min fairness constraint in which the difference between the data rate delivered to all subscribers is minimized. Two variants of the Model are considered - one in which there is no spatial reuse and one in which there is spatial reuse. The study finds that this variant of 802.16j system can deliver significant gains over traditional single-hop access systems: 40% in the case in which there is no spatial reuse and up to 80% when spatial reuse is realised.
N. Nagarajan - One of the best experts on this subject based on the ideXlab platform.
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Integrated Network Topological Control and Key Management for Securing Wireless Sensor Networks
International Journal of Ambient Computing and Intelligence, 2013Co-Authors: S. Kumar, N. NagarajanAbstract:Wireless Sensor Networks WSN have appeared as one of the important fields at present due to their low-cost, self-organizing behavior, sensing ability in inconsiderate environments, and their huge application extent. One of the most challenging topics in relay network is security. The existing Network Topology Acquisition NTA processes for non Transparent Mode relay networks are not effective in providing the security features. At the same time, it is critical to provide privacy and validation in order to prevent information from relay networks. In the proposed system, key management is provided for privacy and simultaneously, validation for security measure is offered with relay nodes. Incorporated Network Topological control and Key management INTK scheme on the relay network provide the effective routing and security solution. INTK Scheme encompasses the incorporation of security and routing, active security, robust re-keying, low complexity and the multiple intensity of encrypt features in relay networks. Security scheme is designed with consideration of the multi cluster based topology control through a multiple intensity keying. The proposed security scheme has low communication energy due to its multi cluster-key executive. INTK Scheme acquires results on 4.5% improved security level with lesser execution time and communication energy consumption. A variety of numerical parameters are computed using ns2 simulator on existing NTA processes for non Transparent Mode relay networks and proposed INTK Scheme. INTK is highly realistic because it is intended to incorporate routing layer and security protocol without sacrificing energy.
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An Improved Network Topology Acquisition process in IEEE 802.16j non-Transparent Mode relay networks
Journal of Discrete Mathematical Sciences and Cryptography, 2012Co-Authors: D. Satish Kumar, N. NagarajanAbstract:Abstract An Improved Network Topology Acquisition process for IEEE 802.16j non Transparent Mode relay networks is presented in this paper. We have implemented this algorithm in NCTUns open source network simulator. In this algorithm the process of setting channel ID for mobile stations, and time taken to accept a new mobile station are mainly focused. The mobile stations which are in the coverage area of base station are given first preference, and those outside coverage area are assigned channel ID through relay stations. Two ID’s are set for each mobile station: Basic channel ID [1, 2, 3….] and Primary Channel ID [256, 257, 258…]. Mobile stations are first accepted by base stations, to allocate band width. We have studied the time taken to accept mobile stations. The results show that, base station takes 0.0096613 sec to accept one mobile station (inside coverage area) and it takes 0.065001 sec to accept one mobile station (outside coverage area)-through a relay station. Here 0.085308 sec is spend to ac...
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Analysis of Transparent and non-Transparent relay Modes in IEEE 802.16j Mobile Multi-Hop relay networks
Journal of Discrete Mathematical Sciences and Cryptography, 2012Co-Authors: D. Satish Kumar, N. NagarajanAbstract:Abstract Two different relay Modes are defined in IEEE 802.16j WIMAX standard: Transparent Mode and non-Transparent Mode. The non Transparent Mode is used to extend the coverage area of base stations, where low cost relay station of equal capacity as that of base station is placed at suitable position. Time taken to accept mobile stations and Bandwidth allocation are main problems in non Transparent Mode. In this we have studied the IEEE 802.16j standard multi hop relay WIMAX networks. We have used relay stations to extend the coverage of base stations. We have also analyzed the throughput between mobile stations with in the coverage area and outside coverage area of base stations. We have simulated the IEEE 802.16j Transparent and non Transparent Mode multi hop WIMAX relay networks using NCTUns Tool.
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A new adaptive Model for throughput enhancement and optimal relay selection in IEEE 802.16j networks
WSEAS TRANSACTIONS on COMMUNICATIONS archive, 2012Co-Authors: D. Satish Kumar, N. NagarajanAbstract:IEEE 802.16 standard is created to compete with cable access networks. In the beginning end users are immobile and have a line of sight with base station, now it moved to mobile non line of sight (NLOS) with the new standard IEEE 802.16e and IEEE 802.16j. The new IEEE 802.16j standard which is an amendment to IEEE 802.16e is mobile multi hop relay (MMR) specification for wireless networks. In this paper we have proposed a new adaptive Model for Transparent Mode IEEE 802.16j MMR networks and studied about the throughput enhancement, optimal relay placement and spatial reuse techniques. We have used four mobile stations (T-MS) connected to Transparent Mode base station (TMR-BS), which are moving at a speed of 20 m/sec. The Mobile Stations are initially placed near to Base Stations and are moving away from Transparent Mode base station. The average throughput achieved without Transparent Mode relay station is 792.045913 Kbps and the average throughput achieved with Transparent Mode relay station is 1261.856667 Kbps. There is 37.2318 % increase in the throughput by placing Transparent Mode relay station at suitable position.
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Simulation of Relay Modes in IEEE 802.16j Mobile Multi-hop Relay (MMR) WIMAX Networks
Innovative Systems Design and Engineering, 2011Co-Authors: Satish Kumar, N. NagarajanAbstract:Two different relay Modes are defined in IEEE 802.16j WIMAX standard: Transparent Mode and non-Transparent Mode. The non Transparent Mode is used to extend the coverage area of base stations, where low cost relay station of equal capacity as that of base station is placed at suitable position. Time taken to accept mobile stations and Bandwidth allocation are main problems in non Transparent Mode. In this we have studied the IEEE 802.16j standard multi hop relay WIMAX networks. We have used relay stations to extend the coverage of base stations. We have also analyzed the throughput between mobile stations with in the coverage area and outside coverage area of base stations. We have simulated the IEEE 802.16j Transparent and non Transparent Mode multi hop WIMAX relay networks using NCTUns Tool
Sean Murphy - One of the best experts on this subject based on the ideXlab platform.
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GLOBECOM - System-Level Performance Evaluation of Multi-Cell Transparent Mode Relay 802.16j Systems
GLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John Murphy, Abdelhamid NafaaAbstract:In this paper, the system capacity of a multi-cell IEEE 802.16j system operating in Transparent Mode is investigated. A previous published analytical Model is used and incorporates interference from neighbouring cells. The Model can be used to determine downlink performance under max-min fairness constraints for both sectored and omnidirectional systems with different amounts of relays. The study provides guidelines on the design of 802.16j systems operating in Transparent Mode - specifically, how to maximise throughput for such systems. It is shown that inter-cell interference from relays is limited in a suburban environment and that relays can deliver significant gains over single hop systems: gains of 30% and 60% can be achieved without and with spatial reuse in an omnidirectional system while 15% and 25% in a sectorised system.
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system level performance evaluation of multi cell Transparent Mode relay 802 16j systems
Global Communications Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John Murphy, Abdelhamid NafaaAbstract:In this paper, the system capacity of a multi-cell IEEE 802.16j system operating in Transparent Mode is investigated. A previous published analytical Model is used and incorporates interference from neighbouring cells. The Model can be used to determine downlink performance under max-min fairness constraints for both sectored and omnidirectional systems with different amounts of relays. The study provides guidelines on the design of 802.16j systems operating in Transparent Mode - specifically, how to maximise throughput for such systems. It is shown that inter-cell interference from relays is limited in a suburban environment and that relays can deliver significant gains over single hop systems: gains of 30% and 60% can be achieved without and with spatial reuse in an omnidirectional system while 15% and 25% in a sectorised system.
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WCNC - Analysis of Transparent Mode IEEE 802.16j System Performance with Varying Numbers of Relays and Associated Transmit Power
2009 IEEE Wireless Communications and Networking Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John MurphyAbstract:In this paper, the system capacity of IEEE 802.16j systems operating in Transparent Mode is investigated under varying numbers of relays and associated transmit power. The study is based on an extended variant of an analytical Model defined in previous work and used to determine the throughput gain that can be achieved under a max-min fairness constraint. The study finds that significant overall throughput gains can be achieved over 802.16e systems: 125% and 55% gain with and without spatial reuse, respectively. However, the overall throughput gain drops as the transmit power at the relays (RSs) decreases despite the fact that a greater number of concurrent transmissions can be achieved due to less interference among the RSs' transmissions. Decreasing the transmit power at the RSs eventually leads to a significant reduction of the achievable throughput gain even though a large number of RSs are deployed in scenarios with or without spatial reuse.
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analysis of Transparent Mode ieee 802 16j system performance with varying numbers of relays and associated transmit power
Wireless Communications and Networking Conference, 2009Co-Authors: Vasken Genc, Sean Murphy, John MurphyAbstract:In this paper, the system capacity of IEEE 802.16j systems operating in Transparent Mode is investigated under varying numbers of relays and associated transmit power. The study is based on an extended variant of an analytical Model defined in previous work and used to determine the throughput gain that can be achieved under a max-min fairness constraint. The study finds that significant overall throughput gains can be achieved over 802.16e systems: 125% and 55% gain with and without spatial reuse, respectively. However, the overall throughput gain drops as the transmit power at the relays (RSs) decreases despite the fact that a greater number of concurrent transmissions can be achieved due to less interference among the RSs' transmissions. Decreasing the transmit power at the RSs eventually leads to a significant reduction of the achievable throughput gain even though a large number of RSs are deployed in scenarios with or without spatial reuse.
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An Interference-Aware Analytical Model for Performance Analysis of Transparent Mode 802.16j Systems
2008 IEEE Globecom Workshops, 2008Co-Authors: Vasken Genc, Sean Murphy, John MurphyAbstract:In this paper, an interference-aware analytical Model of IEEE 802.16j systems operating in Transparent Mode is described. The Model can be used to determine the throughput gain that can be achieved by 802.16J relay- based systems under a max-min fairness constraint in which the difference between the data rate delivered to all subscribers is minimized. Two variants of the Model are considered - one in which there is no spatial reuse and one in which there is spatial reuse. The study finds that this variant of 802.16j system can deliver significant gains over traditional single-hop access systems: 40% in the case in which there is no spatial reuse and up to 80% when spatial reuse is realised.
D. Satish Kumar - One of the best experts on this subject based on the ideXlab platform.
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An Improved Network Topology Acquisition process in IEEE 802.16j non-Transparent Mode relay networks
Journal of Discrete Mathematical Sciences and Cryptography, 2012Co-Authors: D. Satish Kumar, N. NagarajanAbstract:Abstract An Improved Network Topology Acquisition process for IEEE 802.16j non Transparent Mode relay networks is presented in this paper. We have implemented this algorithm in NCTUns open source network simulator. In this algorithm the process of setting channel ID for mobile stations, and time taken to accept a new mobile station are mainly focused. The mobile stations which are in the coverage area of base station are given first preference, and those outside coverage area are assigned channel ID through relay stations. Two ID’s are set for each mobile station: Basic channel ID [1, 2, 3….] and Primary Channel ID [256, 257, 258…]. Mobile stations are first accepted by base stations, to allocate band width. We have studied the time taken to accept mobile stations. The results show that, base station takes 0.0096613 sec to accept one mobile station (inside coverage area) and it takes 0.065001 sec to accept one mobile station (outside coverage area)-through a relay station. Here 0.085308 sec is spend to ac...
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Analysis of Transparent and non-Transparent relay Modes in IEEE 802.16j Mobile Multi-Hop relay networks
Journal of Discrete Mathematical Sciences and Cryptography, 2012Co-Authors: D. Satish Kumar, N. NagarajanAbstract:Abstract Two different relay Modes are defined in IEEE 802.16j WIMAX standard: Transparent Mode and non-Transparent Mode. The non Transparent Mode is used to extend the coverage area of base stations, where low cost relay station of equal capacity as that of base station is placed at suitable position. Time taken to accept mobile stations and Bandwidth allocation are main problems in non Transparent Mode. In this we have studied the IEEE 802.16j standard multi hop relay WIMAX networks. We have used relay stations to extend the coverage of base stations. We have also analyzed the throughput between mobile stations with in the coverage area and outside coverage area of base stations. We have simulated the IEEE 802.16j Transparent and non Transparent Mode multi hop WIMAX relay networks using NCTUns Tool.
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A new adaptive Model for throughput enhancement and optimal relay selection in IEEE 802.16j networks
WSEAS TRANSACTIONS on COMMUNICATIONS archive, 2012Co-Authors: D. Satish Kumar, N. NagarajanAbstract:IEEE 802.16 standard is created to compete with cable access networks. In the beginning end users are immobile and have a line of sight with base station, now it moved to mobile non line of sight (NLOS) with the new standard IEEE 802.16e and IEEE 802.16j. The new IEEE 802.16j standard which is an amendment to IEEE 802.16e is mobile multi hop relay (MMR) specification for wireless networks. In this paper we have proposed a new adaptive Model for Transparent Mode IEEE 802.16j MMR networks and studied about the throughput enhancement, optimal relay placement and spatial reuse techniques. We have used four mobile stations (T-MS) connected to Transparent Mode base station (TMR-BS), which are moving at a speed of 20 m/sec. The Mobile Stations are initially placed near to Base Stations and are moving away from Transparent Mode base station. The average throughput achieved without Transparent Mode relay station is 792.045913 Kbps and the average throughput achieved with Transparent Mode relay station is 1261.856667 Kbps. There is 37.2318 % increase in the throughput by placing Transparent Mode relay station at suitable position.
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Simulation of Hard Hand over (HHO) Mechanism in IEEE 802.16j Transparent Mode networks
International Journal of Computer Applications, 2011Co-Authors: D. Satish KumarAbstract:different relay Modes are defined in IEEE 802.16j WIMAX standard: Transparent Mode and non-Transparent Mode. IEEE 802.16j standard supports mobile station mobility; it defines three kinds of hand over mechanism: hard handover, macro diversity handover (MDHO) and fast BS switching (FBSS) In this paper we have simulated the hard hand over mechanism of IEEE 802.16j Transparent Mode networks using NCTUns Tool. We have used Adaptive modulation and coding scheme. The results show when the mobile station moves form base station 1 (BS1) to base station 2(BS2), it has to disconnect the original connection with BS1 before making a new connection with BS2. And also it shows that the throughput gradually decrease when the mobile station moves to NLOS. Key-Words: - IEEE 802.16j, Transparent Mode, hand over mechanism, NCTUns, throughput etc
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NCTUns Simulation Model for IEEE 802.16j Mobile multi hop Relay (MMR) WIMAX networks
Innovative Systems Design and Engineering, 2011Co-Authors: D. Satish Kumar, NagarajanAbstract:IEEE 802.16j Mobile multi hop relay (MMR) network was approved in the year 2009, by the IEEE 802.16 working committee. In IEEE 802.16j Relay station with same capacity as that of Base station is used to extend the coverage area of base station or used to increase the Throughput capacity of base station. In this paper we have given a simulation Model for IEEE 802.16j MMR networks using the NCTUns -6.0 network simulator. The simulation Model can be used for carry out IEEE 802.16j WiMAX simulations. The NCTUns network simulator is an open source simulator, and it used real time data to carry out the simulation. NCTUns uses a distributed architecture to support remote and concurrent simulations. The NCTUns has 8 components such as GUI, simulation engine, dispatcher, coordinator, kernel level modification, User level demean, parallel simulations for carry out IEEE 802.16j MMR network simulation. Key-Words : - Relay Modes, IEEE 802.16j, NCTUns-6.0, Transparent Mode, non-Transparent Mode, etc
