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Institute of Electrical and Electronics Engineers


Latest Content From Institute of Electrical and Electronics Engineers

Whitepaper: Performance Analysis of a Reuse Partitioning Technique for OFDM Based Evolved UTRA

by Institute of Electrical and Electronics EngineersJan 01, 2008

The current 3GPP working assumption on the Evolved Universal Terrestrial Radio Access (E-UTRA) physical layer is that it will be based on Single Carrier Frequency Division Multiple Access (SC-FDMA) for the uplink and Orthogonal Frequency Division Multiple Access (OFDMA) for the downlink. According to the concept specification, inter-cell interference mitigation techniques applicable to SC-FDMA and OFDMA systems are expected to be the key radio resource management techniques for E-UTRA. In this


Whitepaper: Bounding Performance and Suppressing Intercarrier Interference in Wireless Mobile OFDM

by Institute of Electrical and Electronics EngineersJan 01, 2008

While rapid variations of the fading channel cause InterCarrier Interference (ICI) in Orthogonal Frequency-Division Multiplexing (OFDM), thereby degrading its performance considerably, they also introduce temporal diversity, which can be exploited to improve the performance. This research paper from Institute of Electrical and Electronics Engineers derives a Matched-Filter Bound (MFB) for OFDM transmissions over doubly selective Rayleigh fading channels, which benchmarks the best possible


Whitepaper: Reduced QRD-M Detector in MIMO-OFDM Systems With Partial and Embedded Sorting

by Institute of Electrical and Electronics EngineersJan 01, 2008

MIMO (Multiple-Input-Multiple-Output) technology using multiple antennas at both the transmitter and receiver sides has emerged as a significant breakthrough to increase the system throughput dramatically. Recently, the combination with OFDM (Orthogonal Frequency Division Multiplexing) technology leads to the MIMO-OFDM technology as strong candidate for the 4G wireless systems. This paper published by IEEE presents a novel reduced complexity QRDM for MIMO-OFDM with partial quick sort and


Whitepaper: Modeling Path Capacity in Multi-Hop IEEE 802.11 Networks for QoS Services

by Institute of Electrical and Electronics EngineersJan 01, 2008

QoS provision in multi-hop IEEE 802.11 networks is very challenging due to the interference nature of wireless medium and the contention-based behavior among neighboring nodes. In such networks, one of the key questions for QoS support is: given a specific topology and traffic condition, how much bandwidth can be utilized along a path in the network without violating QoS demand of existing traffic? In this paper from IEEE, an analytical model for multi-hop IEEE 802.11 networks is derived to


Whitepaper: Joint Data Detection and Channel Estimation for OFDM Systems

by Institute of Electrical and Electronics EngineersJan 01, 2008

The researchers developed new blind and semi-blind data detectors and channel estimators for Orthogonal Frequency-Division Multiplexing (OFDM) systems. The data detectors require minimizing a complex, integer quadratic form in the data vector. The semi-blind detector uses both channel correlation and noise variance. The quadratic for the blind detector suffers from rank deficiency; for this, the researchers gave a low-complexity solution. Avoiding a computationally prohibitive exhaustive search,


Whitepaper: On the Influence of Phase Noise Induced ICI in MIMO OFDM Systems

by Institute of Electrical and Electronics EngineersJan 01, 2008

Research concerning multiple-input multiple-output orthogonal frequency division multiplexing (MIMO OFDM) has mainly focused on systems impaired by additive white Gaussian noise (AWGN). This research paper explains the influence of transmitter and receiver phase noise (PN) on the performance of a multiple-input MIMO OFDM based communication system is analyzed. It is shown that in the case of frequency flat Rayleigh fading, the influence of receiver and transmitter PN is equal. In the case of


Whitepaper: Concurrent Subspaces Analysis

by Institute of Electrical and Electronics EngineersJan 01, 2008

A representative subspace is significant for image analysis, while the corresponding techniques often suffer from the curse of dimensionality dilemma. This research paper propose a new algorithm, called Concurrent Subspaces Analysis (CSA), to derive representative subspaces by encoding image objects as 2nd or even higher order tensors. In CSA, an original higher dimensional tensor is transformed into a lower dimensional one using multiple concurrent subspaces that characterize the most


Whitepaper: Complex-Field Coding for OFDM Over Fading Wireless Channels

by Institute of Electrical and Electronics EngineersJan 01, 2008

To improve the average performance of OFDM over random frequency-selective channels, a complex field coding technique is developed which linearly encodes the information symbols through a matrix that introduces a small amount of redundancy in order to robustify the system against frequency-selective fading. Using pairwise error probability analysis, the paper derives expressions for the diversity and coding gains. Next, it identifies conditions for achieving the maximum diversity order.


Whitepaper: Joint Time-Domain Tracking of Channel and Frequency Offset for OFDM Systems

by Institute of Electrical and Electronics EngineersJan 01, 2008

This research paper from Helsinki University of Technology addresses the problem of joint channel and frequency offset estimation and tracking for OFDM (Orthogonal Frequency Division Multiplexing) systems. The proposed method is based on Extended Kalman filtering. The channel taps and the frequency offset are estimated in time-domain while equalization is performed in frequency domain. Simulation results demonstrate accurate tracking capability of the algorithm in scenarios when the channels are


Whitepaper: Adaptive Resource Allocation for Delay Differentiated Traffic in Multiuser OFDM Systems

by Institute of Electrical and Electronics EngineersJan 01, 2008

Most existing work on adaptive allocation of subcarriers and power in multiuser OFDM systems has focused on homogeneous traffic consisting of delay-constrained data or delay-tolerant data only. This research paper investigates the resource allocation problem in a heterogeneous multiuser OFDM system with both Delay-Constrained (DC) and No-Delay-Constrained (NDC) traffic. The objective is to maximize the sum-rate of all the users with NDC traffic while maintaining guaranteed rates for the DC