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34
A Random Matrix Model of Communication via Antenna Arrays
, 2001
"... A random matrix model is introduced that probabilistically describes the spatial and temporal multipath propagation between a transmitting and receiving antenna array with a limited number of scatterers for mobile radio and indoor environments. The model characterizes the channel by its richness d ..."
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Cited by 57 (7 self)
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A random matrix model is introduced that probabilistically describes the spatial and temporal multipath propagation between a transmitting and receiving antenna array with a limited number of scatterers for mobile radio and indoor environments. The model characterizes the channel by its richness delay profile which gives the number of scattering objects as a function of the path delay. Each delay is assigned the eigenvalue distribution of a random matrix that depends on the number of scatterers, receive antennas, and transmit antennas. The model allows to calculate signaltointerferenceandnoise ratios and channel capacities for large antenna arrays analytically and quantifies up to what extent rich scattering improves performance.
Impact of antenna correlation on the capacity of multiantenna channels
 IEEE TRANS. INFORM. THEORY
, 2005
"... This paper applies random matrix theory to obtain analytical characterizations of the capacity of correlated multiantenna channels. The analysis is not restricted to the popular separable correlation model, but rather it embraces a more general representation that subsumes most of the channel model ..."
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Cited by 54 (2 self)
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This paper applies random matrix theory to obtain analytical characterizations of the capacity of correlated multiantenna channels. The analysis is not restricted to the popular separable correlation model, but rather it embraces a more general representation that subsumes most of the channel models that have been treated in the literature. For arbitrary signaltonoise ratios @ A, the characterization is conducted in the regime of large numbers of antennas. For the low and high regions, in turn, we uncover compact capacity expansions that are valid for arbitrary numbers of antennas and that shed insight on how antenna correlation impacts the tradeoffs among power, bandwidth, and rate.
Power Control and Capacity of Spread Spectrum Wireless Networks
 Automatica
, 1999
"... Transmit power control is a central technique for resource allocation and interference management in spreadspectrum wireless networks. With the increasing popularity of spreadspectrum as a multiple access technique, there has been significant research in the area in recent years. While power contr ..."
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Cited by 54 (5 self)
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Transmit power control is a central technique for resource allocation and interference management in spreadspectrum wireless networks. With the increasing popularity of spreadspectrum as a multiple access technique, there has been significant research in the area in recent years. While power control has been considered traditionally as a means to counteract the harmful effect of channel fading, the more general emerging view is that it is a flexible mechanism to provide QualityofService to individual users. In this paper, we will review the main threads of ideas and results in the recent development of this area, with a bias towards issues that have been the focus of our own research. For different receivers of varying complexity, we study both questions about optimal power control as well as the problem of characterizing the resulting network capacity. Although spreadspectrum communications has been traditionally viewed as a physicallayer subject, we argue that by suitable abstr...
An energyefficient approach to power control and receiver design in wireless data networks
 IEEE TRANSACTIONS ON COMMUNICATIONS
, 2005
"... In this work, the crosslayer design problem of joint multiuser detection and power control is studied using a gametheoretic approach that focuses on energy efficiency. The uplink of a directsequence code division multiple access (DSCDMA) data network is considered and a noncooperative game is ..."
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Cited by 45 (14 self)
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In this work, the crosslayer design problem of joint multiuser detection and power control is studied using a gametheoretic approach that focuses on energy efficiency. The uplink of a directsequence code division multiple access (DSCDMA) data network is considered and a noncooperative game is proposed in which users in the network are allowed to choose their uplink receivers as well as their transmit powers to maximize their own utilities. The utility function measures the number of reliable bits transmitted by the user per joule of energy consumed. Focusing on linear receivers, the Nash equilibrium for the proposed game is derived. It is shown that the equilibrium is one where the powers are SIRbalanced with the minimum mean square error (MMSE) detector as the receiver. In addition, this framework is used to study power control games for the matched filter, the decorrelator, and the MMSE detector; and the receivers’ performance is compared in terms of the utilities achieved at equilibrium (in bits/Joule). The optimal cooperative solution is also discussed and compared with the noncooperative approach. Extensions of the results to the case of multiple receive antennas are also presented. In addition, an admission control scheme based on maximizing the total utility in the network is proposed.
MultiCell MIMO Cooperative Networks: A New Look at Interference
 J. Selec. Areas in Commun. (JSAC
, 2010
"... Abstract—This paper presents an overview of the theory and currently known techniques for multicell MIMO (multiple input multiple output) cooperation in wireless networks. In dense networks where interference emerges as the key capacitylimiting factor, multicell cooperation can dramatically improv ..."
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Cited by 35 (14 self)
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Abstract—This paper presents an overview of the theory and currently known techniques for multicell MIMO (multiple input multiple output) cooperation in wireless networks. In dense networks where interference emerges as the key capacitylimiting factor, multicell cooperation can dramatically improve the system performance. Remarkably, such techniques literally exploit intercell interference by allowing the user data to be jointly processed by several interfering base stations, thus mimicking the benefits of a large virtual MIMO array. Multicell MIMO cooperation concepts are examined from different perspectives, including an examination of the fundamental informationtheoretic limits, a review of the coding and signal processing algorithmic developments, and, going beyond that, consideration of very practical issues related to scalability and systemlevel integration. A few promising and quite fundamental research avenues are also suggested. Index Terms—Cooperation, MIMO, cellular networks, relays, interference, beamforming, coordination, multicell, distributed.
On the Asymptotic Eigenvalue Distribution of Concatenated VectorValued Fading Channels
 IEEE INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY, WASHINGTON, DC
, 2001
"... The linear vectorvalued channel x 7! Q n M n x+z with z and M n denoting additive white Gaussian noise and independent random matrices, respectively, is analyzed in the asymptotic regime as the dimensions of the matrices and vectors involved become large. The asymptotic eigenvalue distribution o ..."
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Cited by 27 (4 self)
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The linear vectorvalued channel x 7! Q n M n x+z with z and M n denoting additive white Gaussian noise and independent random matrices, respectively, is analyzed in the asymptotic regime as the dimensions of the matrices and vectors involved become large. The asymptotic eigenvalue distribution of the channel's covariance matrix is given in terms of an implicit equation for its Stieltjes transform as well as an explicit expression for its moments. Additionally, almost all eigenvalues are shown to converge towards zero as the number of factors grows over all bounds. This effect cumulates the total energy in a vanishing number of dimensions. The channel model addressed generalizes the model introduced in [1] for communication via large antennas arrays to N fold scattering per propagation path. As a byproduct, the multiplicative free convolution is shown to extend to a certain class of asymptotically large nonGaussian random covariance matrices. Index terms  random matrices, Stieltjes transform, channel models, fading channels, antenna arrays, multiplicative free convolution, Stransform, Catalan numbers
Design of reducedrank MMSE multiuser detectors using random matrix methods
 IEEE Trans. Inform. Theory
, 2004
"... Abstract—Reducedrank minimum meansquared error (MMSE) multiuser detectors using asymptotic weights have been shown to reduce receiver complexity while maintaining good performance in longsequence codedivision multipleaccess (CDMA) systems. In this paper, we consider the design of reducedrank M ..."
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Cited by 21 (1 self)
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Abstract—Reducedrank minimum meansquared error (MMSE) multiuser detectors using asymptotic weights have been shown to reduce receiver complexity while maintaining good performance in longsequence codedivision multipleaccess (CDMA) systems. In this paper, we consider the design of reducedrank MMSE receivers in a general framework which includes fading, single and multiantenna receivers, as well as directsequence CDMA (DSCDMA) and multicarrier CDMA (both uplink and downlink). In all these cases, random matrix results are used to obtain explicit expressions for the asymptotic eigenvalue moments of the interference autocorrelation matrix and for the asymptotic weights used in the reducedrank receiver. Index Terms—Codedivision multiple access (CDMA), fading channels, minimum meansquared error (MMSE) receivers, multiantenna systems, multicarrier CDMA, multiuser detection, random matrix theory. I.
Asymptotic Eigenvalue Moments for Linear Multiuser Detection
 Communications in Information and Systems
, 2001
"... Using the theory of lattices of noncrossing partitions, an explicit expression for the moments and free cumulants of the asymptotic distribution of certain infinite random matrices is obtained and extended to several cases. From the explicit expression, we give a selfcontained proof of the TseHan ..."
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Cited by 20 (3 self)
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Using the theory of lattices of noncrossing partitions, an explicit expression for the moments and free cumulants of the asymptotic distribution of certain infinite random matrices is obtained and extended to several cases. From the explicit expression, we give a selfcontained proof of the TseHanly formula for the output signaltointerferenceplusnoise ratio of MMSE multiuser detector. We use the moment results to design an asymptotic reducedrank linear multiuser detector. Also we apply these results to analyze linearconjugate MMSE receivers and multiple antenna receivers.
Multicell Uplink Spectral Efficiency of Coded DSCDMA With Random Signatures
, 2001
"... A simple multicell uplink communication model is suggested and analyzed for optimally coded randomly spread direct sequence codedivision multiple access (DSCDMA). The model adheres to Wyner's (1994) infinite linear cellarray model, according to which only adjacentcell interference is present, an ..."
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Cited by 19 (0 self)
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A simple multicell uplink communication model is suggested and analyzed for optimally coded randomly spread direct sequence codedivision multiple access (DSCDMA). The model adheres to Wyner's (1994) infinite linear cellarray model, according to which only adjacentcell interference is present, and characterized by a single parameter 0
Spectral efficiency of multicarrier CDMA
 IEEE Trans. Inf. Theory
, 2005
"... Abstract—We analyze the spectral efficiency (sumrate per subcarrier) of randomly spread synchronous multicarrier codedivision multiple access (MCCDMA) subject to frequencyselective fading in the asymptotic regime of number of users and bandwidth going to infinity with a constant ratio. Both upli ..."
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Cited by 15 (1 self)
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Abstract—We analyze the spectral efficiency (sumrate per subcarrier) of randomly spread synchronous multicarrier codedivision multiple access (MCCDMA) subject to frequencyselective fading in the asymptotic regime of number of users and bandwidth going to infinity with a constant ratio. Both uplink and downlink are considered, either conditioned on the subcarrier fading coefficients (for nonergodic channels) or unconditioned thereon (for ergodic channels). The following receivers are analyzed: a) jointly optimum receiver, b) linear minimum meansquare error (MMSE) receiver, c) decorrelator, and d) singleuser matched filter. Index Terms—Channel capacity, multicarrier codedivision multiple access (MCCDMA), random matrix theory, multiuser