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Transmit diversity in 3G CDMA systems
IEEE Communications Magazine, 2002Transmit diversity (TD) is one of the key contributing technologies to defining the ITU endorsed 3G systems W-CDMA and cdma2000. Spatial diversity is introduced into the signal by transmitting through multiple antennas. The antennas are spaced far enough apart that the signals emanating from them can be assumed to undergo independent fading.
G Mandyam
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Cooperative transmit diversity based on superposition modulation
IEEE Communications Letters, 2005We propose a new strategy for cooperative transmit diversity based on superposition modulation and multiuser detection. The new scheme can outperform "classical" cooperative diversity based on decode-and-forward by about 1.5-2 dB in the SNR range of interest and at the same computational complexity.
Erik G Larsson, B R Vojcic
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A simple transmit diversity technique for wireless communications
IEEE Journal on Selected Areas in Communications, 1998This 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.
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Transmit Diversity in the WCDMA System
International Journal of Wireless Information Networks, 1999This document presents the transmit diversityconcept adopted for the FDD mode of the thirdgenerationWCDMA system in ETSI in 1998. The open-loop mode isbased on the space-time block code attaining full diversity order with two transmit antennas.Different feedback modes are specified.
Risto Wichman, Ari Hottinen
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Joint predistortion and transmit diversity
Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137), 2002This paper presents a scheme for combining joint predistortion (JP) and transmit diversity (Tx diversity). JP is a new baseband processing technique applicable to TDD modems using combined time and code division multiple access. It eliminates intra cell interference at the base station transmitter, allowing for simple code matched filter detectors at ...
Frank Kowalewski, Peter Mangold
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Transmit diversity and spatial multiplexing in four-transmit-antenna OFDM
IEEE International Conference on Communications, 2003. ICC '03., 2004This paper studies a practical design for achieving both spatial diversity and spatial multiplexing in an OFDM system with four transmit antennas. In a certain range of spectral efficiency, the proposed hybrid space-time block coding/multiple-input multiple-output (STBC/MIMO) design is found to be a good design choice based on performance and receiver ...
Xiangyang Zhuang +3 more
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Transmit diversity schemes for CDMA-2000
WCNC. 1999 IEEE Wireless Communications and Networking Conference (Cat. No.99TH8466), 2003Transmit diversity offers an advantage in the forward link of the cdma2000 system by balancing the spectrum efficiency in the uplink and downlink. Three schemes for performing transmit diversity are examined in this paper-orthogonal transmit diversity, time switched transmit diversity, and selection transmit diversity for vehicular, indoor-outdoor ...
Dinesh Rajan, Steven D. Gray
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Geolocation using transmit and receive diversity
IEEE Global Telecommunications Conference, 2004. GLOBECOM '04., 2005Geolocation using received signal strength (RSS) has large errors due to multipath fading, since fading results in high variations in RSS. We show how and when spatial diversity combined with channel knowledge at the receiver can be used to combat fading effects to increase accuracy in location estimation.
Pulkit Grover +2 more
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Transmit diversity as a combination of spatial and delay diversity
2000 IEEE Sixth International Symposium on Spread Spectrum Techniques and Applications. ISSTA 2000. Proceedings (Cat. No.00TH8536), 2002We present performance results of some of the algebraic space-time (ST) block codes based on the combination of Hadamard spreading sequences with rotated constellations. Given a vector x in a rotated constellation in dimension n that has full spatial diversity, we spread each component x/sub j/ of x by a different Hadamard sequence of length n and send
M.O. Damen +2 more
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Transmit diversity for arrays with correlated Rayleigh fading
Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154), 2002Transmit diversity is usually presented for the case of independently faded channels. In this paper the structure of a linear transmitter that can be optimized for a Rayleigh-fading environment in which the fading may be correlated is derived. The transmitter achieves the best mix of array gain-obtained by beamforming, and diversity gain-obtained by ...
Cornelius van Rensburg +1 more
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