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We study and analyze coverage region for MIMO amplify-and-forward (AF) relay network. We consider the network geometry in which L relays are placed uniformly around the source, and assume that there is no direct link between source and destination. We analyze desired transmission rate with the purpose of maximizing coverage region. Using Monte Carlo simulations the impact of number of transceiver...
In this paper a new maximum likelihood (ML) based detector for multi-input multi-output (MIMO) channels in spatio-temporal colored noise fields is proposed. It is assumed a Kronecker model of spatio-temporal correlation of noise. Approximate ML (AML) detection algorithm of MIMO channels is considered for two cases: known noise correlation matrix and unknown noise correlation matrix. The ML decoder...
A phase rotation precoding is proposed for MIMO system to reduce interference caused by transmit correlation. The optimal rotation phases are designed based on maximize the infimum of the set of effective error vectors' norm. Simulation results show the validity of the proposed scheme, which, in the same conditions, improves reliability compared to the other phase rotation precoding scheme.
Multiple-Input Multiple-Output (MIMO) techniques have recently become an important research field for enhancing the performance of in-home Power Line Communication (PLC) systems by exploiting the additional Protective Earth wire. The development of such systems requires an accurate description of the propagation channel. This paper presents a statistical model for the MIMO PLC channel, based on an...
In this paper a statistical description of in-home MIMO power line channels is derived, based on channel measurements in the 0 to 100 MHz range. In particular, it is shown that the power delay profile has a statistical distribution that could be well described by Weibull and Gaussian distributions. It is also confirmed that the channel attenuation has a linear behavior as a function of the frequency...
In this paper we study the characteristics of in-home multi-input multi-output (MIMO) power line channels in the 0 - 100 MHz frequency band. Channel measurements are obtained in several US homes by transmitting two independent signals over two wire pairs (line-neutral and line-protective earth) and receiving on all three wire pairs (line-neutral, line-protective earth and neutral-protective earth)...
Multiple input multiple output (MIMO) communication architecture has spectral efficiencies far beyond those offered by conventional techniques, and is greatly to increase the channel capacity. In this paper, we investigate the MIMO channel capacity in correlated channels using the uniform angular distribution, numerical simulations are performed with Matlab to verify the proposed formula. We prove...
MIMO antenna design is one of biggest issues in the LTE deployment. The multiple antennas should be designed compactly without sacrificing radiation efficiency and spatial correlation. Such multiple antennas can be achieved with polarization antennas or decoupling elements. Conventionally, these antenna parameters are designed empirically. In this paper, a method to optimize multiple antenna directivities...
This paper presents the method to minimize the inter-element mutual coupling in a pair of suspended plate antennas by optimization of the orientation and feed configuration of antenna elements. By reducing the interelement mutual coupling, the envelope correlation coefficient can be suppressed for multiple-input multiple-output (MIMO) antenna systems.
In highly spatially correlated channels the diversity gain achieved by space-frequency (SF) coding is significantly low. Nevertheless, when full or partial channel state information is available at the transmitter, improved performance can be obtained by combining transmit beamforming with SF coding. In this paper we propose two novel transmit beamforming techniques based on the minimum pair-wise...
In this paper, we propose a codebook construction method for multiple-input multiple-output (MIMO) beamforming systems operating under the per-antenna power constraint (PAPC). Under the PAPC which limits the individual power of each transmit antenna, it is known that only phase steering information is required to form the optimal beamforming vector at the transmitter. For systems with non-reciprocal...
Novel representations for the multivariate probability density function (PDF) and cumulative distribution function (CDF) of the equi-correlated non-central chi-square (χ2) distribution are derived. The new representations are given as single integral solutions in terms of well known mathematical functions which are available in common mathematical software packages. The advantage of the new representations...
Mutual coupling between elements in compact transmit antenna arrays is taken into account in performance prediction and system design of multiple-input multi-output (MIMO) systems. The transmitter-end coupling matrix comprised of array impedance matrix and effective load impedance matrix is derived. The impact of transmitter-end mutual coupling on spatial correlation, radiated power, and system capacity...
Application of multiple has attracted many attentions due to their high rate and high. Multiple antennas have a practical drawback, multiple antennas require more radio frequency (RF) chains and it results in higher computational complexity and cost. Besides, in many applications such as the mobile sets we have a limitation of array size to place multiple antennas. This limitation results in mutual...
Most contributions on nonlinear Tomlinson-Harashima precoding (THP) assume complete channel state information (CSI) at the transmitter. However, complete CSI is not available in many wireless systems, and the conventional THP is sensitive to channel mismatch. This article investigates the THP design with imperfect CSI at base station (BS) in spatially correlated multiuser multiple-input multiple-output...
We propose and evaluate the performance of a cascaded THP and BD system (THP-BD) for a MIMO downlink in which BD is used to mitigate multi-user interference and THP is used to mitigate spatial interference. We show that at moderate to high SNR, the cascaded THP-BD system achieves the same error performance as the system employing THP on a multi-user MIMO (MU-MIMO) downlink. Also, symbol error rate...
This paper studies zero-forcing (ZF) detection for multiple-input multiple-output (MIMO) wireless communications systems and transmit-correlated and estimated Rician fading with realistic azimuth spread (AS) and K-factor. Due to the nonzero-mean channel gain matrix, the matrix that determines the symbol-detection signal-to-noise ratio for the spatially multiplexed streams has a noncentral Wishart...
Long Term Evolution (LTE) is an emerging 4G wireless access technology. Multiple-Input Multiple-Output (MIMO) systems are a primary enabler of the high data rate sought to be achieved by LTE. Closed-Loop-Spatial-Multiplexing and Open-Loop-Spatial-Multiplexing are the two primary MIMO transmission modes used in the LTE downlink. An LTE Base Station (eNodeB) is expected to select and switch transmission...
The performance evaluation of the MIMO transmission schemes based on the IEEE 802.16m technology by the system level simulation is conducted in this paper. IEEE 802.16m technology supports various MIMO transmission schemes. We perform the evaluation of the system by applying various MIMO transmission schemes and compare the results. The evaluation results for each channel can be indicator to select...
Minimum-redundancy multiple-input multiple-output (MR-MIMO) antenna arrays - a class of thinned arrays - are introduced. The concepts of convolution array and correlation array are used for data processing required for radar applications but also for optimization of the element distribution in such arrays. An upper bound for the achievable thinning rate is estimated. Particle swarm optimization (PSO)...
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