Search results for "IEEE"

showing 10 items of 135 documents

Performance analysis of the ieee 802.16 arq mechanism

2007

The IEEE 802.16 technology defines the ARQ mechanism that enables a connection to resend data at the MAC level if an error is detected. In this paper, we analyze the key features and parameters of the 802.16 ARQ mechanism. In particular, we consider a choice for the ARQ feedback type, an algorithm to build block sequences, a scheduling of the ARQ feedbacks and retransmissions, the ARQ block rearrangement, ARQ transmission window and ARQ block size. We run a number of simulation scenarios to study these parameters and how they impact a performance of application protocols. The simulation results reveal that the ARQ mechanism and its correct configuration play an important role in transmittin…

Go-Back-N ARQIEEE 802Computer sciencebusiness.industryComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSHybrid automatic repeat requestData_CODINGANDINFORMATIONTHEORYScheduling (computing)Selective Repeat ARQSliding window protocolWirelessError detection and correctionbusinessComputer networkProceedings of the 10th ACM Symposium on Modeling, analysis, and simulation of wireless and mobile systems
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On ARQ feedback intensity of the IEEE 802.16 ARQ mechanism

2008

The IEEE 802.16 standard defines the ARQ mechanism as a part of the MAC layer. The functioning of the ARQ mechanism depends on a number of parameters. The IEEE 802.16 specification defines them but it does not provide concrete values and solutions. We ran simulation scenarios to study how the ARQ feedback intensity impacts the performance of application protocols. The simulation results reveal that a low ARQ feedback intensity results only in a marginal improvement. Though it is possible to optimize the ARQ feedback intensity, it is reasonable to rely upon more frequent ARQ feedback messages as they do not result in a performance degradation. At the same time, ARQ connections, which work on…

Go-Back-N ARQIEEE 802business.industryComputer scienceAutomatic repeat requestComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSHybrid automatic repeat requestData_CODINGANDINFORMATIONTHEORYWiMAXSelective Repeat ARQSliding window protocolTelecommunications linkWirelessForward error correctionbusinessError detection and correctionComputer network2008 International Conference on Telecommunications
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Revisit of RTS/CTS Exchange in High-Speed IEEE 802.11 Networks

2005

IEEE 802.11 medium access control (MAC), called distributed coordination function (DCF), provides two different access modes, namely, 2-way (basic access) and 4-way (RTS/CTS) handshaking. The 4-way handshaking has been introduced in order to combat the hidden terminal phenomenon. It has been also proved that such a mechanism can be beneficial even in the absence of hidden terminals, because of the collision time reduction. We analyze the effectiveness of the RTS/CTS access mode, in current 802.11b and 802.11a networks. Since the rates employed for control frame transmissions can be much lower than the rate employed for data frames, the assumption on the basis of the 4-way handshaking introd…

Hidden node problembusiness.industryComputer scienceReal-time computingFrame (networking)Wireless local area networks (WLAN)Distributed coordination functionThroughputbackoff algorithmHandshakingMedia access controlMultiple Access with Collision Avoidance for WirelessIEEE 802.11e-2005businessCarrier sense multiple access with collision avoidanceComputer networkSixth IEEE International Symposium on a World of Wireless Mobile and Multimedia Networks
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Un metodo single-point basato sulla IEEE 1459-2000 “effective apparent power resolution” per l’individuazione dei carichi disturbanti nei sistemi ele…

2009

IEEE 1459-2000 sistemi di potenza localizzazione delle sorgenti armonicheSettore ING-INF/07 - Misure Elettriche E Elettroniche
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A single-point approach based on nonactive power factor for the assessment of harmonic distortion sources in power systems

2022

This paper presents a study on the use of power factor indicators for the assessment of harmonic distortion sources in power systems. In detail the analysis is focused on the comparison between the proposed nonactive power factor (Q1/N) and the indicators of the IEEE Std. 1459-2010, and on the indicators feasibility in identifying the presence of harmonic distortion sources. As discussed in the paper, the proposed indicator can be evaluated with good accuracy, by means of typical power quantities measurements at the point of common coupling (PCC). Thus its measurement can be feasibly implemented in commercial platforms used for smart metering applications. To verify the proposal validity, s…

IEEE 1459-2010Power QualityPower Ratio QuantitiesSettore ING-INF/07 - Misure Elettriche E Elettroniche2022 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)
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Scheduling solution for the IEEE 802.16 base station

2008

The IEEE 802.16 standard defines a wireless broadband access network technology called WiMAX. It introduces several advantages, one of which is the support for QoS at the MAC level. To ensure meeting the QoS requirements, the 802.16 base station must run some algorithm to allocate slots between connections. This algorithm is not defined in the 802.16 specification but rather is open for alternative implementations. We propose a simple, yet efficient, solution that is capable of allocating slots based on the QoS requirements, bandwidth request sizes, and the 802.16 network parameters. To test the proposed solution, we have implemented the 802.16 MAC and PHY layers in the NS-2 simulator. Seve…

IEEE 802Access networkComputer Networks and CommunicationsComputer sciencebusiness.industryBroadband networksQuality of serviceComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSAccess controlWiMAXScheduling (computing)Base stationPHYResource allocationResource managementbusinessComputer networkComputer Networks
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Handover performance in the IEEE 802.16 mobile networks

2012

The IEEE 802.16 standard provides a full mobility support for stations moving across cell borders. In addition, the WiMAX Forum Network Working Group defines a set of procedures to support handovers in the mobile access network. One of the main characteristics of mobility support is fully controlled and optimized handover (HO), in which a mobile station (MS) migrates from the air interface of one base station (BS) to another one. It is vital to keep the BS transition phase as short as possible to decrease delays and data loss, which is especially crucial for real-time applications, such as VoIP. In this paper we analyze ASN-anchored mobility performance and provide advisable handover relate…

IEEE 802Base stationAccess networkHandoverbusiness.industryComputer scienceAir interfaceMobile stationComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSSoft handoverbusinessWiMAXComputer networkProceedings of the 3rd International ICST Conference on Simulation Tools and Techniques
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Optimal MAC PDU Size in IEEE 802.16

2008

In the IEEE 802.16 the number of errors and the MAC PDU size have an impact on the performance of the network. We present a way to estimate the optimal PDU size and we run a number of simulation scenarios to study these parameters and how they impact on the performance of application protocols. The simulation results reveal that the channel bit error rate has a major impact on the optimal PDU size in the IEEE 802.16 networks. Also, the ARQ block rearrangement influences the performance.

IEEE 802Computer sciencebusiness.industryAutomatic repeat requestComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSReal-time computingHybrid automatic repeat requestData_CODINGANDINFORMATIONTHEORYWiMAXBit error ratebusinessError detection and correctionComputer networkBlock (data storage)Communication channel2008 4th International Telecommunication Networking Workshop on QoS in Multiservice IP Networks
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Performance Evaluation of the IEEE 802.16 ARQ Mechanism

2007

The IEEE 802.16 technology defines the ARQ mechanism that enables a connection to resend data at the MAC level if an error is detected. In this paper, we analyze the key features and parameters of the ARQ mechanism. In particular, we consider a choice for the ARQ feedback type, a scheduling of the ARQ feedbacks and retransmissions, the ARQ block rearrangement, ARQ transmission window and ARQ block size. We run a number of simulation scenarios to study these parameters and how they impact a performance of application protocols. The simulation results reveal that the ARQ mechanism plays an important role in transmitting data over wireless channels in the IEEE 802.16 networks.

IEEE 802Computer sciencebusiness.industryComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSHybrid automatic repeat requestData_CODINGANDINFORMATIONTHEORYScheduling (computing)Selective Repeat ARQSliding window protocolApplication protocolWirelessbusinessBlock sizeComputer network
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Performance comparison of HARQ and ARQ mechanisms in IEEE 802.16 networks

2008

The IEEE 802.16 technology defines several link level mechanisms to retransmit erroneous data. In this paper we compare the performance of the ARQ and HARQ mechanisms in the IEEE 802.16 networks. Our simulations results show that in general HARQ provides a better performance. However, ARQ can compete successfully with it due to a smaller signaling overhead. Furthermore, since ARQ does not require a dedicated uplink signaling channel for the acknowledgments messages, it results in better resources utilization in the uplink direction.

IEEE 802Computer sciencebusiness.industryComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSHybrid automatic repeat requestData_CODINGANDINFORMATIONTHEORYSelective Repeat ARQPerformance comparisonTelecommunications linkOverhead (computing)Link levelbusinessCommunication channelComputer networkProceedings of the 11th international symposium on Modeling, analysis and simulation of wireless and mobile systems
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