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Location Refinement and Power Coverage Analysis Based on distributed antenna

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Transactions of Tianjin University 2016年第1期22卷 7-10页

作者：赵晓楠侯春萍汪清陈华浦亮洲 School of Electronic Information Engineering Tianjin University

To establish wireless channel suitable for the cabin environment, the power coverage was investigated with distributed antenna system and centralized antenna system based on the actual measurement of channel impulse response. The results indicated that the distributed antenna system has more uniform power coverage than the centralized antenna system. The average relative errors of receiving power of both antennas were calculated. The optimal position of the centralized antenna was obtained by Gaussian function refinement, making the system achieve a better transmission power with the same coverage effect, and providing a reference for antenna location in the future real communication in the cabin.

关键词： cabin distributed antenna power coverage

Optimal subcarrier allocation for cognitive radio with multi-user OFDM and distributed antenna

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Journal of Southeast University(English Edition) 2010年第4期26卷 513-517页

作者：葛文栋纪红司鹏搏李曦北京邮电大学泛网无线通信教育部重点实验室北京100876 北京工业大学电子信息与控制工程学院北京100022

The subcarrier allocation problem in cognitive radio（CR）networks with multi-user orthogonal frequency-division multiplexing（OFDM）and distributed antenna is analyzed and modeled for the flat fading channel and the frequency selective channel,where the constraint on the secondary user（SU）to protect the primary user（PU）is that the total throughput of each PU must be above the given threshold instead of the ＂interference temperature＂.According to the features of different types of channels,the optimal subcarrier allocation schemes are proposed to pursue efficiency（or maximal throughput）,using the branch and bound algorithm and the 0-1 implicit enumeration ***,considering the tradeoff between efficiency and fairness,the optimal subcarrier allocation schemes with fairness are proposed in different fading channels,using the pegging *** simulation results illustrate the significant performance improvement of the proposed subcarrier allocation schemes compared with the existing ones in different scenarios.

关键词： cognitive radio subcarrier allocation multi-user OFDM distributed antenna branch and bound algorithm implicit enumeration algorithm pegging algorithm

ESTIMATION OF CARRIER FREQUENCY OFFSETS FOR MIMO SYSTEMS WITH distributed TRANSMIT antennaS

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Journal of Electronics(China) 2007年第4期24卷 455-461页

作者： Deng Kai Tang Youxi Lei Xia Li Shaoqian National Anti-jamming Communications Laboratory University of Electronic Science and Technology of China Chengdu 610054 China

The problem of estimating the carrier frequency offsets in Multiple-Input Multiple-Output (MIMO) systems with distributed transmit antennas is addressed. It is supposed that the transmit antennas are distributed while the receive antennas are still centralized, and the general case where both the time delays and the frequency offsets are possibly different for each transmit antenna is considered. The channel is supposed to be frequency flat, and the macroscopic fading is also taken into consideration. A carrier frequency offset estimator based on Maximum Likelihood (ML) is proposed, which can separately estimate the frequency offset for each transmit antenna and exploit the spatial diversity. The Cramer-Rao Bound (CRB) for synchronous MIMO (i.e., the time delays for each transmit antenna are all equal) is also derived. Simulation results are given to illustrate the per- formance of the estimator and compare it with the CRB. It is shown that the estimator can provide satisfactory frequency offset estimates and its performance is close to the CRB for the Signal-to-Noise Ratio (SNR) below 20dB.

关键词： Multiple-Input Multiple-Output (MIMO) distributed antenna Carrier frequency offset estimation Maximum Likelihood (ML) Cramer-Rao Bound (CRB)