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Mohamedslim Alouini - One of the best experts on this subject based on the ideXlab platform.
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on the Ergodic Capacity of dual branch correlated log normal fading channels with applications
Vehicular Technology Conference, 2015Co-Authors: Hessa Alquwaiee, Mohamedslim AlouiniAbstract:Closed-form expressions of the Ergodic Capacity of independent or correlated diversity branches over Log-Normal fading channels are not available in the literature. Thus, it is become of an interest to investigate the behavior of such metric at high signal-to-noise (SNR). In this work, we propose simple closed-form asymptotic expressions of the Ergodic Capacity of dual-branch correlated Log- Normal corresponding to selection combining, and switch-and-stay combining. Furthermore, we capitalize on these new results to find new asymptotic Ergodic Capacity of correlated dual- branch free-space optical communication system under the impact of pointing error with both heterodyne and intensity modulation/direct detection.
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VTC Spring - On the Ergodic Capacity of Dual-Branch Correlated Log-Normal Fading Channels with Applications
2015 IEEE 81st Vehicular Technology Conference (VTC Spring), 2015Co-Authors: Hessa Alquwaiee, Mohamedslim AlouiniAbstract:Closed-form expressions of the Ergodic Capacity of independent or correlated diversity branches over Log-Normal fading channels are not available in the literature. Thus, it is become of an interest to investigate the behavior of such metric at high signal-to-noise (SNR). In this work, we propose simple closed-form asymptotic expressions of the Ergodic Capacity of dual-branch correlated Log- Normal corresponding to selection combining, and switch-and-stay combining. Furthermore, we capitalize on these new results to find new asymptotic Ergodic Capacity of correlated dual- branch free-space optical communication system under the impact of pointing error with both heterodyne and intensity modulation/direct detection.
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A Novel Ergodic Capacity Analysis of Diversity Combining and Multihop Transmission Systems over Generalized Composite Fading Channels
arXiv: Information Theory, 2012Co-Authors: Ferkan Yilmaz, Mohamedslim AlouiniAbstract:Ergodic Capacity is an important performance measure associated with reliable communication at the highest rate at which information can be sent over the channel with a negligible probability of error. In the shadow of this definition, diversity receivers (such as selection combining, equal-gain combining and maximal-ratio combining) and transmission techniques (such as cascaded fading channels, amplify-and-forward multihop transmission) are deployed in mitigating various performance impairing effects such as fading and shadowing in digital radio communication links. However, the exact analysis of Ergodic Capacity is in general not always possible for all of these forms of diversity receivers and transmission techniques over generalized composite fading environments due to it's mathematical intractability. In the literature, published papers concerning the exact analysis of Ergodic Capacity have been therefore scarce (i.e., only [1] and [2]) when compared to those concerning the exact analysis of average symbol error probability. In addition, they are essentially targeting to the Ergodic Capacity of the maximal ratio combining diversity receivers and are not readily applicable to the Capacity analysis of the other diversity combiners / transmission techniques. In this paper, we propose a novel moment generating function-based approach for the exact Ergodic Capacity analysis of both diversity receivers and transmission techniques over generalized composite fading environments. As such, we demonstrate how to simultaneously treat the Ergodic Capacity analysis of all forms of both diversity receivers and multihop transmission techniques.
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Ergodic Capacity of cognitive radio under imperfect channel state information
IEEE Transactions on Vehicular Technology, 2012Co-Authors: Zouheir Rezki, Mohamedslim AlouiniAbstract:A spectrum-sharing communication system where the secondary user is aware of the instantaneous channel-state information (CSI) of the secondary link but knows only the statistics and an estimated version of the secondary transmitter-primary receiver link is investigated. The optimum power profile and the Ergodic Capacity of the secondary link are derived for general fading channels [with a continuous probability density function (pdf)] under the average and peak transmit power constraints and with respect to the following two different interference constraints: 1) an interference outage constraint and 2) a signal-to-interference outage constraint. When applied to Rayleigh fading channels, our results show, for example, that the interference constraint is harmful at the high-power regime, because the Capacity does not increase with the power, whereas at the low-power regime, it has a marginal impact and no-interference performance, which corresponds to the Ergodic Capacity under average or peak transmit power constraint in the absence of the primary user, may be achieved.
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Ergodic Capacity of cognitive radio under imperfect channel state information
arXiv: Information Theory, 2012Co-Authors: Zouheir Rezk, Mohamedslim AlouiniAbstract:A spectrum-sharing communication system where the secondary user is aware of the instantaneous channel state information (CSI) of the secondary link, but knows only the statistics and an estimated version of the secondary transmitter-primary receiver (ST-PR) link, is investigated. The optimum power profile and the Ergodic Capacity of the secondary link are derived for general fading channels (with continuous probability density function) under average and peak transmit-power constraints and with respect to two different interference constraints: an interference outage constraint and a signal-to-interference outage constraint. When applied to Rayleigh fading channels, our results show, for instance, that the interference constraint is harmful at high-power regime in the sense that the Capacity does not increase with the power, whereas at low-power regime, it has a marginal impact and no-interference performance corresponding to the Ergodic Capacity under average or peak transmit power constraint in absence of the primary user, may be achieved.
Shi Jin - One of the best experts on this subject based on the ideXlab platform.
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On the Ergodic Capacity of mmWave Systems Under Finite-Dimensional Channels
IEEE Transactions on Wireless Communications, 2019Co-Authors: Xi Yang, Xiao Li, Shengli Zhang, Shi JinAbstract:Due to the underlying sparse structure of the mmWave channels, which indeed makes the exact closed-form Capacity expressions inherently hard to derive, there has been less research on the Ergodic Capacity of mmWave systems. To overcome this problem, by means of the majorization theory, this paper analyzes the Ergodic Capacity of point-to-point mmWave communication systems under finite-dimensional channel model. In particular, we derive several closed-form Ergodic Capacity approximations, which exhibit excellent tightness in spite of whether the steering matrices are singular or not. Then, several Jensen's approximations and bounds of the Ergodic Capacity are also derived. The results indicate that the Ergodic Capacity seems to increase logarithmically with the number of antennas, the transmit SNR per antenna, and the eigenvalues of the steering matrix products. Besides, the DFT matrices can effectively characterize the spatial directions of mmWave channels when the number of antennas grows large. After that, high-SNR Ergodic Capacity, high-SNR slope, and power offset are also analyzed. It indicates that for a finite-dimensional channel, the maximum multiplexing gain increases with the number of paths instead of the number of antennas in Rayleigh channels. Numerical simulations are performed to validate the results.
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Ergodic Capacity analysis of amplify and forward mimo dual hop systems
International Symposium on Information Theory, 2008Co-Authors: Shi Jin, Caijun Zhong, Matthew R Mckay, Kai-kit WongAbstract:This paper analyzes the Ergodic Capacity of dual-hop amplify-and-forward (AF) multiple-input multiple-output (MIMO) relay channels, assuming that the channel state information is available only at the destination terminal. We first present a new expression for the unordered eigenvalue density of a certain product of independent complex matrices, which is used to derive an exact expression for Ergodic Capacity. We then employ results from multivariate statistics to derive new closed-form upper and lower bounds of the Ergodic Capacity. In contrast to prior work, our results apply for arbitrary numbers of antennas and arbitrary relay configurations. Numerical results are provided to validate the theoretical analysis.
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ISIT - On the Ergodic Capacity of MIMO Nakagami-fading channels
2008 IEEE International Symposium on Information Theory, 2008Co-Authors: Caijun Zhong, Kai-kit Wong, Shi JinAbstract:This paper investigates the Ergodic Capacity limit of multiple-input multiple-output (MIMO) Nakagami-fading channels for arbitrary finite number of antennas. Through the use of majorization theory, we derive Ergodic Capacity bounds for this general class of channels. In the high signal-to-noise-ratio (SNR) regime, we show that a simple expression for the Capacity upper bound is available, which reveals the impact of channel fading parameter on the system Ergodic Capacity. Besides, the asymptotic behavior of the Ergodic Capacity where the number of antenna(s) at one or both side(s) goes to infinity, is studied. By considering the low SNR regime, on the other hand, we give an approximation and a lower bound for the Ergodic Capacity. Monte Carlo simulation results are provided to verify the tightness of the proposed bounds.
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ISIT - Ergodic Capacity analysis of amplify-and-forward MIMO dual-hop systems
2008 IEEE International Symposium on Information Theory, 2008Co-Authors: Shi Jin, Caijun Zhong, Matthew R Mckay, Kai-kit WongAbstract:This paper analyzes the Ergodic Capacity of dual-hop amplify-and-forward (AF) multiple-input multiple-output (MIMO) relay channels, assuming that the channel state information is available only at the destination terminal. We first present a new expression for the unordered eigenvalue density of a certain product of independent complex matrices, which is used to derive an exact expression for Ergodic Capacity. We then employ results from multivariate statistics to derive new closed-form upper and lower bounds of the Ergodic Capacity. In contrast to prior work, our results apply for arbitrary numbers of antennas and arbitrary relay configurations. Numerical results are provided to validate the theoretical analysis.
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On the Ergodic Capacity of Rank- $1$ Ricean-Fading MIMO Channels
IEEE Transactions on Information Theory, 2007Co-Authors: Shi Jin, Xiqi Gao, Xiaohu YouAbstract:This paper investigates the Ergodic Capacity of Ricean-fading multiple-input-multiple-output (MIMO) channels with rank-1 mean matrices under the assumption that the channel is unknown at the transmitter and perfectly known at the receiver. After introducing the system model and the concept of Ergodic Capacity of MIMO channels, we derive the explicit expressions for the expected values of the determinant and log-determinant of complex noncentral Wishart matrices. Subsequently, we obtain new upper and lower bounds on the Ergodic Capacity of rank-1 Ricean-fading MIMO channels at any signal-to-noise ratio (SNR). We show that our bounds are tighter than previously reported analytical bounds, and discuss the impact of spatial fading correlation and Ricean K-factor with the help of these bounds. Furthermore, we extend the analysis of Ergodic Capacity to frequency selective spatially correlated Ricean-fading MIMO channels. We demonstrate that the calculation of Ergodic Capacity of frequency selective fading MIMO channels can be converted to the calculation of the one of equivalent frequency flat-fading MIMO channels. Finally, we present numerical results that confirm the theoretical analysis
Yahong Rosa Zheng - One of the best experts on this subject based on the ideXlab platform.
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On the Ergodic Capacity of MIMO Triply Selective Rayleigh Fading Channels
IEEE Transactions on Wireless Communications, 2008Co-Authors: Chengshan Xiao, Yahong Rosa ZhengAbstract:The Ergodic Capacity is investigated for triply selective MIMO Rayleigh fading channels. A mathematical formula is derived for the Ergodic Capacity in the case when the channel state information is known to the receiver but unknown to the transmitter. A closed-form formula is derived that quantifies the effect of the frequency-selective fading on the Ergodic Capacity into an intersymbol interference (ISI) degradation factor. Different from the existing conclusion that the frequency-selective fading channel has the same Ergodic Capacity as the frequency flat fading channel, we show that the discrete-time inter-tap correlated frequency-selective fading channel has smaller Ergodic Capacity than the frequency flat fading channel. Only in the special case when the fading does not have ISI inter-tap correlations will the Ergodic Capacity be the same as that of the frequency flat channel. Theoretical derivation and computer simulation demonstrate that the inter-tap correlations can have more significant impact on the Ergodic Capacity than the spatial correlations.
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WCNC - Ergodic Capacity of doubly selective Rayleigh fading MIMO channels
2004 IEEE Wireless Communications and Networking Conference (IEEE Cat. No.04TH8733), 2004Co-Authors: Chengshan Xiao, Yahong Rosa ZhengAbstract:The Ergodic Capacity is investigated for doubly selective (frequency selective and time varying) MIMO Rayleigh fading channels. A closed form formula is derived that quantifies the effect of the ISI fading on the Ergodic Capacity into an ISI degradation factor. It is discovered that, in general frequency selective MIMO channels, the inter-tap correlations of the ISI fading will reduce the Ergodic Capacity comparing to the frequency flat fading channel. Only in the special case when the ISI fading does not have inter-tap correlations will the Ergodic Capacity be the same as that of the frequency flat channel. This new formula is mathematically proved and experimentally verified via Monte-Carlo simulations.
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GLOBECOM - Ergodic Capacity of MIMO triply selective Rayleigh fading channels
IEEE Global Telecommunications Conference 2004. GLOBECOM '04., 1Co-Authors: Chengshan Xiao, Yahong Rosa ZhengAbstract:New results are presented for the Ergodic Capacity of spatially-correlated, time-varying and frequency-selective (i.e., triply selective) MIMO Rayleigh fading channels. Simplified Capacity formulas are also derived for special cases such as SIMO and MISO triply selective fading channels. A closed form formula is proposed that quantifies the effect of the frequency-selective fading on the Ergodic Capacity into an intersymbol interference (ISI) degradation factor. It is discovered that, in general frequency-selective MIMO channels, the ISI inter-tap correlations reduce the Ergodic Capacity compared to the frequency flat fading channel. Only in the special case when the fading does not have ISI inter-tap correlations will the Ergodic Capacity be the same as that of the frequency flat channel. The new Capacity results are experimentally verified via Monte-Carlo simulations.
Chengshan Xiao - One of the best experts on this subject based on the ideXlab platform.
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On the Ergodic Capacity of MIMO Triply Selective Rayleigh Fading Channels
IEEE Transactions on Wireless Communications, 2008Co-Authors: Chengshan Xiao, Yahong Rosa ZhengAbstract:The Ergodic Capacity is investigated for triply selective MIMO Rayleigh fading channels. A mathematical formula is derived for the Ergodic Capacity in the case when the channel state information is known to the receiver but unknown to the transmitter. A closed-form formula is derived that quantifies the effect of the frequency-selective fading on the Ergodic Capacity into an intersymbol interference (ISI) degradation factor. Different from the existing conclusion that the frequency-selective fading channel has the same Ergodic Capacity as the frequency flat fading channel, we show that the discrete-time inter-tap correlated frequency-selective fading channel has smaller Ergodic Capacity than the frequency flat fading channel. Only in the special case when the fading does not have ISI inter-tap correlations will the Ergodic Capacity be the same as that of the frequency flat channel. Theoretical derivation and computer simulation demonstrate that the inter-tap correlations can have more significant impact on the Ergodic Capacity than the spatial correlations.
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WCNC - Ergodic Capacity of doubly selective Rayleigh fading MIMO channels
2004 IEEE Wireless Communications and Networking Conference (IEEE Cat. No.04TH8733), 2004Co-Authors: Chengshan Xiao, Yahong Rosa ZhengAbstract:The Ergodic Capacity is investigated for doubly selective (frequency selective and time varying) MIMO Rayleigh fading channels. A closed form formula is derived that quantifies the effect of the ISI fading on the Ergodic Capacity into an ISI degradation factor. It is discovered that, in general frequency selective MIMO channels, the inter-tap correlations of the ISI fading will reduce the Ergodic Capacity comparing to the frequency flat fading channel. Only in the special case when the ISI fading does not have inter-tap correlations will the Ergodic Capacity be the same as that of the frequency flat channel. This new formula is mathematically proved and experimentally verified via Monte-Carlo simulations.
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GLOBECOM - Ergodic Capacity of MIMO triply selective Rayleigh fading channels
IEEE Global Telecommunications Conference 2004. GLOBECOM '04., 1Co-Authors: Chengshan Xiao, Yahong Rosa ZhengAbstract:New results are presented for the Ergodic Capacity of spatially-correlated, time-varying and frequency-selective (i.e., triply selective) MIMO Rayleigh fading channels. Simplified Capacity formulas are also derived for special cases such as SIMO and MISO triply selective fading channels. A closed form formula is proposed that quantifies the effect of the frequency-selective fading on the Ergodic Capacity into an intersymbol interference (ISI) degradation factor. It is discovered that, in general frequency-selective MIMO channels, the ISI inter-tap correlations reduce the Ergodic Capacity compared to the frequency flat fading channel. Only in the special case when the fading does not have ISI inter-tap correlations will the Ergodic Capacity be the same as that of the frequency flat channel. The new Capacity results are experimentally verified via Monte-Carlo simulations.
Ming Chen - One of the best experts on this subject based on the ideXlab platform.
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Joint power control and user pairing for Ergodic Capacity maximization in V2V communications
2017 9th International Conference on Wireless Communications and Signal Processing (WCSP), 2017Co-Authors: Yinlu Wang, Yijin Pan, Zhaohui Yang, Ming ChenAbstract:In vehicle-to-vehicle (V2V) communication underlaying cellular networks, interference between cellular users (CUEs) and V2V users (VUEs) can be severe. To address this issue, many studies focused on designing resource allocation schemes to mitigate uplink interference. Most of them investigated the instantaneous resource allocation. In this paper, however, we consider a highway scenario where CUEs' demands are to maintain high throughput all along the way instead of just at a specific position. To meet the demands, we study the resource allocation scheme that maximizes the sum position Ergodic Capacity for the first time. Firstly, the expression for the position Ergodic Capacity of any given CUE is derived. Secondly, a resource allocation problem is formulated to maximize the sum position Ergodic Capacity of all the paired CUEs, subject to different quality of service (QoS) constraints of CUEs and VUEs. Thirdly, the optimization problem is divided into two sub-problems, namely the power allocation and the user pairing sub-problems. A robust algorithm is designed to jointly solve these two. Finally, simulation results show that this algorithm can reduce the computational cost significantly with a small performance gap to the global optimum.
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WCSP - Joint power control and user pairing for Ergodic Capacity maximization in V2V communications
2017 9th International Conference on Wireless Communications and Signal Processing (WCSP), 2017Co-Authors: Yinlu Wang, Yijin Pan, Zhaohui Yang, Ming ChenAbstract:In vehicle-to-vehicle (V2V) communication underlaying cellular networks, interference between cellular users (CUEs) and V2V users (VUEs) can be severe. To address this issue, many studies focused on designing resource allocation schemes to mitigate uplink interference. Most of them investigated the instantaneous resource allocation. In this paper, however, we consider a highway scenario where CUEs' demands are to maintain high throughput all along the way instead of just at a specific position. To meet the demands, we study the resource allocation scheme that maximizes the sum position Ergodic Capacity for the first time. Firstly, the expression for the position Ergodic Capacity of any given CUE is derived. Secondly, a resource allocation problem is formulated to maximize the sum position Ergodic Capacity of all the paired CUEs, subject to different quality of service (QoS) constraints of CUEs and VUEs. Thirdly, the optimization problem is divided into two sub-problems, namely the power allocation and the user pairing sub-problems. A robust algorithm is designed to jointly solve these two. Finally, simulation results show that this algorithm can reduce the computational cost significantly with a small performance gap to the global optimum.
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WCSP - Ergodic Capacity of distributed antenna systems over Shadowed Nakagami-m fading Channels
2013 International Conference on Wireless Communications and Signal Processing, 2013Co-Authors: Yun-peng Wen, Jin-yuan Wang, Ming ChenAbstract:This paper focuses on the downlink Ergodic Capacity of distributed antenna systems (DAS) over Shadowed Nakagamim fading Channels. A composite channel is established, which includes both large-scale fading and small-scale fading. Then, the probability density function (PDF) of the output signal-to-noise ratio (SNR) is derived. To facilitate the analysis, the distribution of the output SNR is approximated by a lognormal distribution. After that, by using Gauss-Hermite integration, an approximate analytical expression of the Capacity for a mobile station (MS) over a given place is derived. Furthermore, by employing the composite Simpson's rule, a closed-form expression of the Ergodic Capacity is obtained. Numerical results show that the derived analytical expression of Ergodic Capacity can provide very well approximation to the simulation results.