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- Space-Time/Frequency Coding for MIMO-OFDM in Next Generation Broadband Wireless Systems
- With the advent of the next generation (4G) broadband wireless communications, the combination of Multiple-Input Multiple-Output MIMO wireless technology with Orthogonal Frequency Division Multiplexing OFDM has been recognized as one of the most promising techniques to support high data rate and high performance. In particular, coding over the space, time...
- Tags: Broadband Wireless, Broadband, MIMO-OFDM, Broadband Internet, Telecommunications, Wireless
- White papers 2007-03-17
- Approaching MIMO-OFDM Capacity With Closed-Loop V-BLAST
- This paper studies schemes for partial channel feedback in Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) block-fading channels. This paper presents a closed-loop extension of the Vertical Bell Labs Layered Space-Time (V-BLAST) architecture for which the transmit power and rate assignments for each transmit antenna at different OFDM tones are...
- Tags: IEEE, MIMO-OFDM, OFDM, Wireless
- White papers 2007-02-05
- Optimal Training Signals for MIMO OFDM Channel Estimation in the Presence of Frequency Offset and Phase Noise
- The authors develop robust Mean-Square Error MSE-optimal training signal designs for multiple-input multiple-output orthogonal frequency-division multiplexing channel estimation with frequency offset and Phase Noise PN, and present analytical and simulation results for the frequency-offset and PN effects on channel estimation. The proposed designs are more advantageous for moderate-to-high values of...
- Tags: Frequency, Training, MIMO-OFDM, Channel Estimation, OFDM, Workforce Management, Wireless, Human Resources
- White papers 2006-10-01
- Linear Precoding for Multiuser MIMO-OFDM Systems
- This paper develops linear precoding schemes for the downlink in multiuser Multiple-Input Multiple-Output MIMO Orthogonal Frequency Division Multiplexing OFDM systems with multiple data streams per user. The authors extend an existing multiuser MIMO algorithm, that jointly optimizes the power allocation and the transmit and receive filters, to MIMOOFDM systems. One...
- Tags: MIMO, Allocation, MIMO-OFDM, University Of Toronto, OFDM, Wireless
- White papers 2006-09-28
- Performance of Antenna Selection for MIMO-OFDM Systems Based on Measured Indoor Correlated Frequency Selective Channels
- This paper presents and compares antenna selection strategies for frequency selective MIMO-OFDM channels. Real channels are measured, and used to evaluate performance. Results for simulated TGn channel models are also presented. The paper shows that the capacity gain predicted from the simulated channels, is significantly lower than can be achieved...
- Tags: Channel, Performance, MIMO-OFDM
- White papers 2006-08-14
- Transmit Optimization for MIMO-OFDM With Delay-Constrained and No-Delay-Constrained Traffic
- This paper studies low-complexity power control schemes to approach the capacity limits of Multiple-Input Multiple-Output Orthogonal-Frequency-Division-Multiplexing (MIMO-OFDM) channels under the assumption that perfect Channel State Information CSI is available at both the transmitter and the receiver. Two notions of channel capacity limit are considered, namely, the ergodic capacity for variable-rate...
- Tags: Optimization, Capacity, MIMO-OFDM
- White papers 2006-08-01
- Rapid MIMO-OFDM Software Defined Radio System Prototyping
- Multiple Input-Multiple Output MIMO is an attractive technology for future wireless systems. MIMO communication, enabled by the use of multiple transmit and multiple receive antennas, is known for its high spectral efficiency as well as its robustness against fading and interference. Combining MIMO with Orthogonal Frequency Division Multiplexing OFDM, it...
- Tags: Radio, MIMO, MIMO-OFDM, OFDM, Wireless
- White papers 2006-06-20
- On the Use of Adaptive Loading Algorithms in MIMO-OFDM Systems
- In this paper, Optimum adaptive loading algorithms are applied to Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing MIMOOFDM system. Chaw's and Compello's algorithms have been implemented to obtain a bit and power allocation for each subcarrier assuming instantaneous channel knowledge. Channel matrix Singular Value Decomposition SVD method has been employed in...
- Tags: Algorithm, MIMO-OFDM, Chaw, Engineering
- White papers 2006-04-19
- Compress-and-Forward Cooperative Relaying in MIMO-OFDM Systems
- This paper investigates the capacity of Compress-and-Forward (C&F) cooperative relaying scheme when the C&F relay operates in Time Division Duplex TDD. In the evaluation it considers MIMO-OFDM transmission. An achievable rate was previously derived in assuming scalar channel. This paper extends this Wyner-Ziv bound to MIMO-OFDM, by applying results from...
- Tags: MIMO-OFDM
- White papers 2006-04-13
- Recursive and Trellis-Based Feedback Reduction for MIMO-OFDM With Rate-Limited Feedback
- This paper investigates an adaptive MIMO-OFDM system with a feedback link that can only convey a finite number of bits. This paper considers three different transmitter configurations; beamforming applied per OFDM subcarrier; precoded spatial multiplexing applied per subcarrier; and precoded orthogonal space time block coding applied per subcarrier. Depending on...
- Tags: Transmitter, Feedback, MIMO-OFDM, OFDM, Wireless
- White papers 2006-03-16
- A Space-Time Receiver for MIMO-OFDM Ad Hoc Networks
- This paper proposes a receiver architecture that can demodulate multiple data streams with different frequency offsets and propagation delays in Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) ad hoc networks. The receiver performs joint synchronization and interference cancellation to separate these interfering data streams and achieve synchronization for...
- Tags: Frequency, University Of Texas, MIMO-OFDM, Receiver, OFDM, Wireless
- White papers 2006-03-01
- Spatial Multiplexing for Outdoor MIMO-OFDM Systems With Limited Feedback Constraint
- This paper proposes a spatial multiplexing technique for the downlink of a Multiple-Input-Multiple-Output MIMO Orthogonal-Frequency-Division-Multiplexing OFDM system. For outdoor environments with a limited angular spread at the base station, the proposed technique is able to separate the users' streams through a joint spatial processing at both the transmitter and the...
- Tags: Technique, Uppsala University, MIMO-OFDM, Transmission, Productivity, OFDM, Wireless
- White papers 2006-02-22
- Reconfigurable Antenna Solution for MIMO-OFDM Systems
- A reconfigurable microstrip dipole antenna solution for Multiple Input Multiple Output MIMO communication systems making use of Orthogonal Frequency Division Multiplexing OFDM is presented. When applied to closely spaced antenna arrays, this method can increase link capacity. The benefits of this novel antenna solution are demonstrated by channel capacity measurements...
- Tags: Drexel University, MIMO-OFDM, Antenna Solution, OFDM, Wireless
- White papers 2006-01-23
- Interpolation Based Transmit Beamforming for MIMO-OFDM With Limited Feedback
- Transmit beamforming and receive combining are simple methods for exploiting spatial diversity in Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system. Optimal beamforming requires channel state information in the form of the beamforming vectors for each OFDM subcarrier. This paper proposes to a limited feedback architecture that combines beamforming vector...
- Tags: Vector, Transmitter, IEEE, MIMO-OFDM, OFDM, Wireless
- White papers 2005-11-11
- Space-Frequency Bit-Interleaved Coded Modulation for MIMO-OFDM
- This paper presents the design of a novel space-frequency bit-interleaver for MIMO-OFDM systems. The proposed Space-Frequency Interleaver SFI interleaves convolutionally coded bits across transmit antennas and frequency tones. Performance is analyzed for a simplified channel model and is demonstrated for a modeled IEEE 802.16e OFDM PHY layer using ITU channel...
- Tags: Performance, Stanford University, MIMO-OFDM, Space-frequency Interleaver, OFDM, Wireless
- White papers 2005-11-02
- Diversity Analysis for Frequency-Selective MIMO-OFDM Systems With General Spatial and Temporal Correlation Model
- In this paper, the effect of a general spatial and temporal fading correlation structure on the performance of coded MIMO-OFDM systems is studied. The analysis handles an arbitrary joint transmit-receive spatial correlation model including the non-Kronecker model. An upper bound on the maximum achievable diversity order for frequency-selective MIMO-OFDM systems...
- Tags: Diversity, MIMO-OFDM, Analysis
- White papers 2005-08-09
- A Software and Hardware Evaluation of Revolutionary Turbo MIMO OFDM Schemes for 5GHz WLANs
- Globally, WLANs operating in the 5GHz band have been standardized by the IEEE North America, ETSI Europe and ARIB Japan. A harmonized physical layer is specified offering up to 54 Mbits/s using rate adaptive Coded Orthogonal Frequency Division Multiplexing COFDM. Multiple Input Multiple Output MIMO antenna architectures coupled with Soft...
- Tags: Software, WLAN, Hardware, MIMO-OFDM, Wireless LANs, LANs, Wi-Fi, Wireless, Networking
- White papers 2005-08-01
- On the Influence of Phase Noise Induced ICI in MIMO OFDM Systems
- The influence of transmitter and receiver Phase Noise PN on the performance of a Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing 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...
- Tags: Influence, Transmitter, IEEE, MIMO-OFDM, OFDM, Wireless
- White papers 2005-08-01
- Quantized Multi-Mode Precoding for Spatial Multiplexing MIMO-OFDM Systems
- Spatial multiplexing with multi-mode precoding can achieve both high capacity and high reliability in Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems. Multimode precoding uses linear transmit precoding but adapts the number of transmit streams or modes according to the channel conditions. Multi-mode precoding typically requires complete knowledge of the transmit...
- Tags: Algorithm, University Of Texas, MIMO-OFDM, Engineering
- White papers 2005-06-25
- Using MIMO-OFDM Technology to Boost Wireless LAN Performance Today
- This White Paper describes how MIMO-OFDM (Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing) technology delivers significant performance improvements for wireless LANs, enabling them to serve existing applications more cost-effectively as well as making new, more demanding applications possible. It also explains how manufacturers and end-users can profit by deploying MIMO-OFDM...
- Tags: WLAN, MIMO-OFDM, Wireless LANs, LANs, Wi-Fi, Wireless, Networking
- White papers 2005-06-01
