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MULTIPLE CHANNELS

by Ursula Y. Sullivan, Jacquelyn S. Thomas, Jacquelyn S. Thomas
"... Recent industry studies suggest that customers routinely use multiple channels of the same retailer to make their purchases. However, most studies about the drivers of customer profitability only focus on customer behavior in a single channel. This research investigates customer channel migration an ..."
Abstract - Cited by 1 (0 self) - Add to MetaCart
Recent industry studies suggest that customers routinely use multiple channels of the same retailer to make their purchases. However, most studies about the drivers of customer profitability only focus on customer behavior in a single channel. This research investigates customer channel migration

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 1165 (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

Capacity of multi-antenna Gaussian channels

by I. Emre Telatar - EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS , 1999
"... We investigate the use of multiple transmitting and/or receiving antennas for single user communications over the additive Gaussian channel with and without fading. We derive formulas for the capacities and error exponents of such channels, and describe computational procedures to evaluate such form ..."
Abstract - Cited by 2923 (6 self) - Add to MetaCart
We investigate the use of multiple transmitting and/or receiving antennas for single user communications over the additive Gaussian channel with and without fading. We derive formulas for the capacities and error exponents of such channels, and describe computational procedures to evaluate

Packet Switching In Radio Channels: Part III -- Polling and . . .

by Fouad A. Tobagi, Leonard Kleinrock - IEEE TRANSACTIONS ON COMMUNICATIONS , 1976
"... Here we continue the analytic study of packet switching in radio channels which we reported upon in our two previous papers [ 11, [2]. Again we consider a population of terminals communicating with a central station over a packet-switched radio channel. The allocation of bandwidth among the contend ..."
Abstract - Cited by 517 (5 self) - Add to MetaCart
, (as expected) random access is superior to both futed assignment and polling. We also introduce and analyze a dynamic reservation technique which we call split-channel reservation multiple access (SRMA) which is interesting in that it is both simple and efficient over a large range of system

Multi-Channel MAC for Ad Hoc Networks: Handling Multi-Channel Hidden Terminals Using a Single Transceiver

by Jungmin So, Nitin Vaidya - In ACM MobiHoc , 2004
"... This paper proposes a medium access control (MAC) protocol for ad hoc wireless networks that utilizes multiple channels dynamically to improve performance. The IEEE 802.11 standard allows for the use of multiple channels available at the physical layer, but its MAC protocol is designed only for a si ..."
Abstract - Cited by 431 (6 self) - Add to MetaCart
This paper proposes a medium access control (MAC) protocol for ad hoc wireless networks that utilizes multiple channels dynamically to improve performance. The IEEE 802.11 standard allows for the use of multiple channels available at the physical layer, but its MAC protocol is designed only for a

On limits of wireless communications in a fading environment when using multiple antennas

by G. J. Foschini, M. J. Gans - Wireless Personal Communications , 1998
"... Abstract. This paper is motivated by the need for fundamental understanding of ultimate limits of bandwidth efficient delivery of higher bit-rates in digital wireless communications and to also begin to look into how these limits might be approached. We examine exploitation of multi-element array (M ..."
Abstract - Cited by 2426 (14 self) - Add to MetaCart
communication links. We explore the important case when the channel characteristic is not available at the transmitter but the receiver knows (tracks) the characteristic which is subject to Rayleigh fading. Fixing the overall transmitted power, we express the capacity offered by MEA technology and we see how

Capacity of a Mobile Multiple-Antenna Communication Link in Rayleigh Flat Fading

by Thomas L. Marzetta, Bertrand M. Hochwald
"... We analyze a mobile wireless link comprising M transmitter and N receiver antennas operating in a Rayleigh flat-fading environment. The propagation coefficients between every pair of transmitter and receiver antennas are statistically independent and unknown; they remain constant for a coherence int ..."
Abstract - Cited by 495 (22 self) - Add to MetaCart
interval of T symbol periods, after which they change to new independent values which they maintain for another T symbol periods, and so on. Computing the link capacity, associated with channel coding over multiple fading intervals, requires an optimization over the joint density of T M complex transmitted

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 811 (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

Space-time codes for high data rate wireless communication: Performance criterion and code construction

by Vahid Tarokh, Nambi Seshadri, A. R. Calderbank - IEEE TRANS. INFORM. THEORY , 1998
"... We consider the design of channel codes for improving the data rate and/or the reliability of communications over fading channels using multiple transmit antennas. Data is encoded by a channel code and the encoded data is split into n streams that are simultaneously transmitted using n transmit ant ..."
Abstract - Cited by 1782 (28 self) - Add to MetaCart
We consider the design of channel codes for improving the data rate and/or the reliability of communications over fading channels using multiple transmit antennas. Data is encoded by a channel code and the encoded data is split into n streams that are simultaneously transmitted using n transmit

Achieving near-capacity on a multiple-antenna channel

by Bertrand M. Hochwald, Stephan Ten Brink - IEEE Trans. Commun , 2003
"... Recent advancements in iterative processing of channel codes and the development of turbo codes have allowed the communications industry to achieve near-capacity on a single-antenna Gaussian or fading channel with low complexity. We show how these iterative techniques can also be used to achieve nea ..."
Abstract - Cited by 402 (2 self) - Add to MetaCart
near-capacity on a multiple-antenna system where the receiver knows the channel. Combining iterative processing with multiple-antenna channels is particularly challenging because the channel capacities can be a factor of ten or more higher than their single-antenna counterparts. Using a “list ” version
Results 1 - 10 of 18,289