Multi-input Multi-output Wireless Channels Research Articles

Energy Efficient Resource Allocation for Wireless Power Transfer Enabled Collaborative Mobile Clouds

In order to fully enjoy high rate broadband multimedia services, prolonging the battery lifetime of user equipment is critical for mobile users, especially for smartphone users. In this paper, the problem of distributing cellular data via a wireless power transfer enabled collaborative mobile cloud (WeCMC) in an energy efficient manner is investigated. WeCMC is formed by a group of users who have both functionalities of information decoding and energy harvesting, and are interested for cooperating in downloading content from the operators. Through device-to-device communications, the users inside WeCMC are able to cooperate during the downloading procedure and offload data from the base station to other WeCMC members. When considering multi-input multi-output wireless channel and wireless power transfer, an efficient algorithm is presented to optimally schedule the data offloading and radio resources in order to maximize energy efficiency as well as fairness among mobile users. Specifically, the proposed framework takes energy minimization and quality of service requirement into consideration. Performance evaluations demonstrate that a significant energy saving gain can be achieved by the proposed schemes.

Modeling and Performance Evaluation of Dual Polarized MIMO Land Mobile Satellite Channels

paper is concerned with generating of narrow-band dual polarized Multi Input Multi Output (MIMO) over land Mobile Satellite (LMS) fading channels. In the absence of accurate experimental results of MIMO-LMS channels, a statistical model for the characterization of MIMO-LMS is proposed based on available experimental results for Single Input Single output (SISO) LMS and MIMO wireless channels as well as on their extrapolation to the MIMO-LMS case of interest. In this paper a step-by-step methodology for transforming SISO model (Loo model) to MIMO model with detailed description and block diagrams for the simulation and time series signal generation for MIMO-LMS, with the desired power, probability distribution, covariance relations and spectrum. Moreover, based on the proposed channel model, the channel capacity statistics as well as the error performance of MIMO- LMS are evaluated through computer simulation. Useful numerical results on the capacity are also provided taking into account several operational system parameters. The simulation model and results are useful for LMS-MIMO physical layer researches and system designer, who need an easy to implement and realizable model, representative of typical MIMO-LMS communication systems.

Motion-Compensated Scalable Video Transmission Over MIMO Wireless Channels

We study motion compensated fine granular scalable (MC-FGS) video transmission over multiinput multioutput (MIMO) wireless channels applicable to video streaming, where leaky and partial prediction schemes are applied in the enhancement layer of MC-FGS to exploit the tradeoff between error propagation and coding efficiency. For reliable transmission, we propose unequal error protection (UEP) by considering a tradeoff between reliability and data rates, which are controlled by forward error correction and MIMO mode selection to minimize the average distortion. In a high Doppler environment, where it is hard to get an accurate channel estimate, we investigate the performance of the proposed MC-FGS video transmission scheme with joint control of both the leaky and partial prediction parameters, and the UEP. In a slow fading channel, where the channel throughput can be estimated at the transmitter, adaptive control of prediction parameters is considered.

Characterization and modeling of MIMO wireless channels based on correlation tensor

This paper presents the characterization and modeling of several correlative channel models, namely, the Kronecker, Weichselberger, and structured models for multi-input multi-output (MIMO) systems. Due to its simplicity, the Kronecker model is by far the most popular MIMO channel model in the literature. It greatly simplifies channel analysis, as it holds that scatterers around the transmitter fade independently of those around the receiver. Despite its popularity, the Kronecker model has been shown to be inaccurate. The Weichselberger model uses the eigenvalue decomposition (EVD) of the channel as its parameters, and in most cases, is more accurate than the Kronecker model. The structured model is an extension of the Weichselberger model to the wideband MIMO channel. It uses tensors to express the wideband MIMO channel in an elegant fashion, often with fewer parameters than the Kronecker model.

On the Diversity-Multiplexing Tradeoff in MIMO Wireless Channels at Finite SNRs

In this paper, a new framework to characterize the tradeoff between diversity and multiplexing gains of Multi Input Multi Output (MIMO) wireless systems at finite Signal to Noise Ratios (SNRs) is presented. By suitable definitions of non-asymptotic diversity and multiplexing gains, we extract a useful tool to investigate the performance of space-time schemes at finite SNRs. Exact results on the diversity-multiplexing tradeoff (DMT) are derived for Multi Input Single Output (MISO), Single Input Multi Output (SIMO), and 2 × 2 MIMO channels. We show that our outcomes coincide with the Zheng and Tse's results at high SNRs. When the new definitions of non-asymptotic diversity and multiplexing gains are used, the resulted DMT converges to its asymptotic value at realistic SNRs. Furthermore, using these definitions enables the diversity gain to represent the outage probability with reasonable accuracy.