Results 1 - 10 of 135,664

Performance of Ultra-Wideband Communications with Suboptimal Receivers in Multipath Channels

by John D. Choi, Wayne E. Stark - IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS , 2002
"... The performance of a single-user ultra-wideband (UWB) communication system employing binary block-coded pulse-position modulation (PPM) and suboptimal receivers in multipath channels is considered. The receivers examined include a rake receiver with various diversity combining schemes and an autocor ..."
Abstract - Cited by 156 (0 self) - Add to MetaCart
The performance of a single-user ultra-wideband (UWB) communication system employing binary block-coded pulse-position modulation (PPM) and suboptimal receivers in multipath channels is considered. The receivers examined include a rake receiver with various diversity combining schemes

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 2878 (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

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
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

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
fundamental tradeo# between how much of each any coding scheme can get. For the richly scattered Rayleigh fading channel, we give a simple characterization of the optimal tradeo# curve and use it to evaluate the performance of existing multiple antenna schemes.

Namgoong Ultra-Wideband Radio

by Robert A. Scholtz, Moe Z. Win, I. A Rationale, Impulse Radio - Journal of Applied Signal Processing, EURASIP publishing
"... Impulse radio, a form of ultra-wide band signaling, has properties that make it a viable candidate for short range communications in dense multipath environments. This paper describes the characteristics of impulse radio, gives analytical estimates of its multiple access capability, and presents pro ..."
Abstract - Cited by 22 (1 self) - Add to MetaCart
Impulse radio, a form of ultra-wide band signaling, has properties that make it a viable candidate for short range communications in dense multipath environments. This paper describes the characteristics of impulse radio, gives analytical estimates of its multiple access capability, and presents

I. ULTRA-WIDEBAND SIGNALS AND POSITIONING APPLICATIONS A. Ultra-Wideband Signals

by Sinan Gezici, H. Vincent Poor, Bfrac B
"... The high time resolution of ultra-wideband (UWB) signals facilitates very precise position estimation in many scenarios, which makes a variety applications possible. This paper reviews the problem of position estimation in UWB systems, beginning with an overview of the basic structure of UWB signals ..."
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The high time resolution of ultra-wideband (UWB) signals facilitates very precise position estimation in many scenarios, which makes a variety applications possible. This paper reviews the problem of position estimation in UWB systems, beginning with an overview of the basic structure of UWB

Low Complexity Rake Receivers in Ultra-Wideband Channels

by D. Cassioli, M. Z. Win, F. Vatalaro, A. F. Molisch - IEEE Trans. Wireless Commun , 2007
"... One of the major issues for the design of ultra-wideband (UWB) receivers is the need to recover the signal energy dispersed over many multipath components, while keeping the receiver complexity low. To this aim we consider two schemes for reduces-complexity UWB Rake receivers, both of which combine ..."
Abstract - Cited by 26 (2 self) - Add to MetaCart
One of the major issues for the design of ultra-wideband (UWB) receivers is the need to recover the signal energy dispersed over many multipath components, while keeping the receiver complexity low. To this aim we consider two schemes for reduces-complexity UWB Rake receivers, both of which combine

A Channelized Digital Ultra-Wideband Receiver

by Won Namgoong - IEEE Trans. Wireless Comm , 2003
"... Abstract—A channelized digital ultrawideband (UWB) receiver that efficiently samples the UWB signal at a fraction of the chip frequency is proposed. The received signal is channelized in the frequency domain by employing a bank of mixers and low-pass filters. After sampling at a much reduced frequen ..."
Abstract - Cited by 32 (6 self) - Add to MetaCart
Abstract—A channelized digital ultrawideband (UWB) receiver that efficiently samples the UWB signal at a fraction of the chip frequency is proposed. The received signal is channelized in the frequency domain by employing a bank of mixers and low-pass filters. After sampling at a much reduced

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

Ultra-Wideband Antenna in Coplanar Technology

by Hung-jui Lam, Hung-jui Lam, Hung-jui Lam
"... ii ..."
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Results 1 - 10 of 135,664