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Cross-layer Design of Optimal Adaptation Technique over Selection-Combining Diversity Nakagami-m Fading Channels

by Ashok K. Karmokar, Vijay K. Bhargava
"... Abstract — Adaptive modulation and antenna diversity are two important enabling techniques for future wireless network to meet demand for high data rate transmission. We study a Markov decision process based cross-layer design of optimal adaptation policy over selection-combining Nakagami-m fading c ..."
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Abstract — Adaptive modulation and antenna diversity are two important enabling techniques for future wireless network to meet demand for high data rate transmission. We study a Markov decision process based cross-layer design of optimal adaptation policy over selection-combining Nakagami-m fading

Capacity Limits of MIMO Channels

by Andrea Goldsmith, Syed Ali Jafar, Nihar Jindal, Sriram Vishwanath - IEEE J. SELECT. AREAS COMMUN , 2003
"... We provide an overview of the extensive recent results on the Shannon capacity of single-user and multiuser multiple-input multiple-output (MIMO) channels. Although enormous capacity gains have been predicted for such channels, these predictions are based on somewhat unrealistic assumptions about t ..."
Abstract - Cited by 409 (17 self) - Add to MetaCart
, for each definition, different correlation models and channel information assumptions that we consider. We first provide a comprehensive summary of ergodic and capacity versus outage results for single-user MIMO channels. These results indicate that the capacity gain obtained from multiple antennas heavily

Optimal Packet Scheduling using Adaptive M-QAM and Orthogonal STBC in MIMO Nakagami-m Fading Channels

by Ashok K. Karmokar, Student Member, Vijayk. Bhargava
"... Abstract — We study a cross-layer optimization problem of a rate-adaptive MQAM system that maximizes throughput, and minimizes packet error rate, delay and overflow using the framework of Markov decision process. We consider finite size buffer and random incoming traffic arrivals. The fading channel ..."
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Abstract — We study a cross-layer optimization problem of a rate-adaptive MQAM system that maximizes throughput, and minimizes packet error rate, delay and overflow using the framework of Markov decision process. We consider finite size buffer and random incoming traffic arrivals. The fading

Diversity and Multiplexing: A Fundamental Tradeoff in Multiple Antenna Channels

by Lizhong Zheng, David N. C. Tse - IEEE Trans. Inform. Theory , 2002
"... Multiple antennas can be used for increasing the amount of diversity or the number of degrees of freedom in wireless communication systems. In this paper, we propose the point of view that both types of gains can be simultaneously obtained for a given multiple antenna channel, but there is a fund ..."
Abstract - Cited by 1143 (20 self) - Add to MetaCart
Multiple antennas can be used for increasing the amount of diversity or the number of degrees of freedom in wireless communication systems. In this paper, we propose the point of view that both types of gains can be simultaneously obtained for a given multiple antenna channel, but there is a

Opportunistic Beamforming Using Dumb Antennas

by Pramod Viswanath, David Tse, Rajiv Laroia - IEEE Transactions on Information Theory , 2002
"... Multiuser diversity is a form of diversity inherent in a wireless network, provided by independent time-varying channels across the different users. The diversity benefit is exploited by tracking the channel fluctuations of the users and scheduling transmissions to users when their instantaneous cha ..."
Abstract - Cited by 801 (1 self) - Add to MetaCart
channel quality is near the peak. The diversity gain increases with the dynamic range of the fluctuations and is thus limited in environments with little scattering and/or slow fading. In such environments, we propose the use of multiple transmit antennas to induce large and fast channel fluctuations so

Fading Channels: Information-Theoretic And Communications Aspects

by Ezio Biglieri, John Proakis, Shlomo Shamai (Shitz) - IEEE TRANSACTIONS ON INFORMATION THEORY , 1998
"... In this paper we review the most peculiar and interesting information-theoretic and communications features of fading channels. We first describe the statistical models of fading channels which are frequently used in the analysis and design of communication systems. Next, we focus on the information ..."
Abstract - Cited by 416 (3 self) - Add to MetaCart
In this paper we review the most peculiar and interesting information-theoretic and communications features of fading channels. We first describe the statistical models of fading channels which are frequently used in the analysis and design of communication systems. Next, we focus

Cross-Layer Design for Wireless Networks

by Sanjay Shakkottai, Peter C. Karlsson - IEEE Communications Magazine , 2003
"... As the cellular and PCS world collides with Wireless LANs and Internet-based packet data, new networking approaches will support the integration of voice and data on the composite infrastructure of cellular base stations and Ethernet-based wireless access points. This paper highlights some of the pa ..."
Abstract - Cited by 249 (3 self) - Add to MetaCart
of the past accomplishments and promising research avenues for an important topic in the creation of future wireless networks. In this paper, we address the issue of cross-layer networking, where the physical and MAC layer knowledge of the wireless medium is shared with higher layers, in order to provide

Fading relay channels: Performance limits and space-time signal design

by Rohit U. Nabar, Helmut Bölcskei, Felix W. Kneubühler - IEEE J. SELECT. AREAS COMMUN , 2004
"... Cooperative diversity is a transmission technique where multiple terminals pool their resources to form a virtual antenna array that realizes spatial diversity gain in a distributed fashion. In this paper, we examine the basic building block of cooperative diversity systems, a simple fading relay ch ..."
Abstract - Cited by 436 (4 self) - Add to MetaCart
of the paper is devoted to (distributed) space-time code design for fading relay channels operating in the AF mode. We show that the corresponding code design criteria consist of the traditional rank and determinant criteria for the case of co-located antennas as well as appropriate power control rules

A simple transmit diversity technique for wireless communications

by Siavash M. Alamouti - IEEE Journal on Selected Areas in Communications , 1998
"... Abstract — This paper presents a simple two-branch transmit diversity scheme. Using two transmit antennas and one receive antenna the scheme provides the same diversity order as maximal-ratio receiver combining (MRRC) with one transmit antenna, and two receive antennas. It is also shown that the sch ..."
Abstract - Cited by 2084 (0 self) - Add to MetaCart
that the scheme may easily be generalized to two transmit antennas and M receive antennas to provide a diversity order of 2M. The new scheme does not require any bandwidth expansion any feedback from the receiver to the transmitter and its computation complexity is similar to MRRC. Index Terms—Antenna array

1 On the MIMO Channel Capacity for the Nakagami-m Channel

by Gustavo Fraidenraich, Student Member, Olivier Lévêque Member, John M. Cioffi
"... Abstract — This paper presents the MIMO channel capacity over the Nakagami-m fading channel. The joint eigenvalue density function of W = HH † , where H is the channel matrix, is derived in a closed form in the 2 × 2 case and for integer values of m, as well as for m → ∞. The marginal eigenvalue dis ..."
Abstract - Cited by 4 (0 self) - Add to MetaCart
Abstract — This paper presents the MIMO channel capacity over the Nakagami-m fading channel. The joint eigenvalue density function of W = HH † , where H is the channel matrix, is derived in a closed form in the 2 × 2 case and for integer values of m, as well as for m → ∞. The marginal eigenvalue
Results 1 - 10 of 60,091