Results 221 to 230 of about 40,980 (259)
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Coded OFDM-IM With Transmit Diversity
IEEE Transactions on Communications, 2017In this paper, we propose a simple transmit diversity scheme for orthogonal frequency division multiplexing (OFDM) with index modulation (IM) in order to achieve a diversity gain for index detection, which can significantly improve the performance of OFDM-IM at the cost of the spectral efficiency.
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Cooperative Transmit Diversity via Superpostion Coding
EUROCON 2005 - The International Conference on "Computer as a Tool", 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 ...
E.G. Larsson, B.R. Vojcic
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Extension of 3GPP transmit diversity system
IEEE 60th Vehicular Technology Conference, 2004. VTC2004-Fall. 2004, 2005In this paper, we extend the 3GPP transmit diversity system by increasing the number of antenna elements from 2 to 4, to improve the BER performance. The increase of feedback signal message bits is kept low. The effect of spacing distance between antennas, control delay time and the maximum Doppler frequency on BER performance is studied under flat ...
M. Shokair, Y. Akaiwa
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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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Multicarrier CDMA systems with transmit diversity
Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152), 2002Transmit diversity was previously proposed to reduce the detrimental effects in fading channels. In this paper we apply the space-time block codes to multicarrier CDMA systems. Our emphasis is on designing receivers that can decode the space-time codes and suppress the multiple access interference.
null Xiaodong Cai, A.N. Akansu
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Orthogonal Space-Time Spreading Transmit Diversity
IEICE Transactions on Communications, 2005In this paper, a new 2-antenna transmit diversity, called orthogonal space-time spreading transmit diversity (OSTSTD) combined with delay transmission, is proposed. At the transmitter, N data symbols to be transmitted are spread using N different orthogonal space-time spreading codes (each represented by N x N matrix) and are transmitted from two ...
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Phase rotation Maximum Transmit Diversity code
Proceedings of 2011 International Conference on Electronic & Mechanical Engineering and Information Technology, 2011In order to improve the reliability of Maximum Transmit Diversity (MTD) code in block fading channel, phase rotation MTD code is proposed in this paper. Through phase rotation of the transmitted signals, the burst decoding error is changed into random error at the receiver, which can be corrected easily.
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Mobile transmit diversity for base‐station antenna arrays
Microwave and Optical Technology Letters, 2001AbstractFor base‐station antenna arrays operating at 1.8 GHz in urban vehicular environments, we experimentally investigate the spatial diversity provided by transmitting from the mobile terminal with two λ/2 dipole antennas that are separated by λ/2 and arranged in copolarized (CP) and cross‐polarized (XP) configurations.
Kavak, ADNAN, Xu, GH
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Adaptive Transmit Diversity with Quadrant Phase Constraining Feedback
Wireless Personal Communications, 2005An adaptive transmit diversity scheme with quadrant phase constraining feedback is proposed in this paper. With simple linear operations at both transmitter and receiver, the proposed algorithm can achieve better system performances with only 2M-2 bits of feedback information for systems with M transmit antennas.
J. Wu, H. Horng, J. Zhang, C. Xiao
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Sequence Estimation with Transmit Diversity for Wireless Communications
AEU - International Journal of Electronics and Communications, 2003Abstract In this paper, an optimum sequence estimation algorithm for wireless systems with Alamouti's two transmitter diversity in the presence of multipath fading is proposed. The algorithm is based on a jointly iterative channel and sequence estimation according to the maximum likelihood (ML) criterion, using the Expectation-Maximization (EM ...
Panayırcı, Erdal +2 more
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