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BER analysis of TDD downlink multiuser MIMO systems with imperfect channel state information

Baolong Zhou, Lingge Jiang, Shengjie Zhao, Chen He
2011 EURASIP Journal on Advances in Signal Processing  
Because of the constraints of the TDD frame structure and the uplink pilot overhead, there inevitably exists CSI delay and channel estimation error between CSI estimation and downlink transmission channel  ...  In time division duplex (TDD) systems, the base station estimates CSI based on uplink pilots and then uses it through channel reciprocity to generate the precoding matrix in the downlink transmission.  ...  Moreover, by comparing Figures 6 and 8 , we can find that the impact of the speed of user on BER is similar to the impact of CSI delay M d on BER and the big speed value is equivalent to the big CSI delay  ... 
doi:10.1186/1687-6180-2011-104 fatcat:hu556nv3rzafbaolfb76d6c6bm

Exploiting the Increasing Correlation of Space Constrained Massive MIMO for CSI Relaxation

Adrian Garcia-Rodriguez, Christos Masouros
2016 IEEE Transactions on Communications  
The proposed scheme is based on collecting CSI for only a subset of antennas during the pilot training stage and, subsequently, using averages of the acquired CSI for the remaining closely-spaced antennas  ...  To characterize this tradeoff, we explore the impact that the number of antennas with instantaneous CSI has on the performance, signal processing complexity, and energy efficiency of time-division duplex  ...  Distribution of the CSI on the Antenna Array The definition of B, C and f (·) impacts the performance and complexity of the proposed scheme.  ... 
doi:10.1109/tcomm.2016.2538222 fatcat:3svtdw7d5rg23fum3fptf6gljy

Designing PSAM schemes: How optimal are SISO pilot parameters for spatially correlated SIMO?

Xiangyun Zhou, Tharaka A. Lamahewa, Parastoo Sadeghi, Salman Durrani
2008 2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications  
We investigate the optimum design parameters, including the ratio of power allocated to the pilots and the fraction of time occupied by the pilots, for SIMO systems with different antenna sizes and with  ...  independent and correlated SIMO systems for the same fading rate and signal-to-noise ratio (SNR).  ...  ACKNOWLEDGEMENTS This work was supported by the Australian Research Council Discovery Grant DP0773898.  ... 
doi:10.1109/pimrc.2008.4699449 dblp:conf/pimrc/ZhouLSD08 fatcat:ntsi6emarngk7l4y5mctuhixcy

Exploiting Wireless Channel State Information Structures Beyond Linear Correlations: A Deep Learning Approach [article]

Zhiyuan Jiang, Sheng Chen, Andreas F. Molisch, Rath Vannithamby, Sheng Zhou, Zhisheng Niu
2018 arXiv   pre-print
However, the acquisition of timely and accurate CSI has long been considered as a major issue, and becomes increasingly challenging due to the need for obtaining CSI of many antenna elements in massive  ...  To cope with this challenge, existing works mainly focus on exploiting linear structures of CSI, such as CSI correlations in the spatial domain, to achieve dimensionality reduction.  ...  , at the expense of requiring large amounts of training data and corresponding computational power.  ... 
arXiv:1812.00541v1 fatcat:txdaaoiwc5hdvamcgaorzcpe6e

Recent Advances in Acquiring Channel State Information in Cellular MIMO Systems

Gábor Fodor, László Pap, Miklós Telek
2019 Infocommunications journal  
Therefore, cellular MU-MIMO systems employ predefined pilot sequences and configure associated time, frequency, code and power resources to facilitate the acquisition of high quality CSI for data transmission  ...  Therefore, cellular MU-MIMO systems employ predefined pilot sequences and configure associated time, frequency, code and power resources to facilitate the acquisition of high quality CSI for data transmission  ...  That work does not explicitly model the impact of CSI errors on MU-MIMO receivers, such as an MMSE receiver.  ... 
doi:10.36244/icj.2019.3.2 fatcat:xuvq575enbb4ncbrmhp7wlxwha

Massive MIMO: Enhancement of Spectral and Energy Efficiency for 5G Perspective

Prasad Rayi, Acharya Nagarjuna University, Makkapati Prasad, Rayapati Venkata Rangarao & Jagarlamudi Chandramouli College of Engineering
2019 International Journal of Intelligent Engineering and Systems  
This paper evaluates the impact of perfect and imperfect channel state information (CSI) on the SE.  ...  Massive Multi-Input and Multi-Output (MIMO) antenna system is considered as the key technology to improve both spectral efficiency (SE) and energy efficiency (EE) for 5G wireless systems.  ...  The pilot signals used in one cell affect the pilot signals in another cell. Since the PC limits the achievable data rate and transmitted power at the BS.  ... 
doi:10.22266/ijies2019.0228.30 fatcat:pijt3pulvjh47mkv4iffcvs3gy

An Overview of Massive MIMO: Benefits and Challenges

Lu Lu, Geoffrey Ye Li, A. Lee Swindlehurst, Alexei Ashikhmin, Rui Zhang
2014 IEEE Journal on Selected Topics in Signal Processing  
We particularly focus on the potential impact of pilot contamination caused by the use of non-orthogonal pilot sequences by users in adjacent cells.  ...  Massive multiple-input multiple-output (MIMO) wireless communications refers to the idea equipping cellular base stations (BSs) with a very large number of antennas, and has been shown to potentially allow  ...  ACKNOWLEDGMENT The authors would like to thank Prof. D. Gesbert with EURECOM for valuable comments and suggestions to improve the quality of this article. The authors would also like to thank Mr. Y.  ... 
doi:10.1109/jstsp.2014.2317671 fatcat:x3hzg3mmizanlnei4lir6z6m4a

Impact of User Number on Massive MIMO with a Practical Number of Antennas

Wael Boukley Hasan, Paul Harris, Angela Doufexi, Mark Beach
2018 2018 IEEE 87th Vehicular Technology Conference (VTC Spring)  
These results were based on perfect channel state information (CSI), Shannon capacity calculations or using a very large number of antennas at the base station (BS).  ...  As opposed to the aforementioned results, we show that the maximum sum SE with practical number of antennas could be achieved by decreasing the number of users before the sum SE reached its peak value.  ...  Cumulative error amplification is derived to illustrate the impact of channel hardening and the number of users on amplifying the effect of the errors caused by hardware impairments.  ... 
doi:10.1109/vtcspring.2018.8417581 dblp:conf/vtc/HasanHDB18 fatcat:fxrvtbaf3rd5lhuqiexxrrtq5e

Interference Suppression for Multiuser Downlink Transmission in Frequency-Selective Fading Channels

Li Guo, Yih-Fang Huang
2008 IEEE Transactions on Signal Processing  
The proposed scheme effectively suppresses the ISI with a zero-forcing constraint on the CCI, and provides a viable solution to an otherwise analytically complex, if not unsolvable, problem.  ...  Frequency-domain transmit beamforming and pre-equalization based on single-carrier frequency-domain equalization (SC-FDE) technique are employed to cancel co-channel interference (CCI) and to suppress  ...  One approach to estimate the CSI is for the BTS to transmit pilots during some downlink pilot slot. Users estimate the downlink channel based on the received pilot signals and then feedback to BTS.  ... 
doi:10.1109/tsp.2008.925958 fatcat:w7rpanou4zeahk5nfhaueaeygi

Analysis and Evaluation of Performance Gains and Tradeoffs for Massive MIMO Systems

Saba Jabbar, Yu Li
2016 Applied Sciences  
A linear increasing in data rate means that with large number of antennas many tens of terminals can be served simultaneously within the same bandwidth using the same transmit power, so the overall spectral  ...  The same property that makes massive MIMO flexible against fading also makes the technology very resistant to failure of one or a few of the antenna units.  ...  I would like to express my grateful and thankful to the Chinese Scholarship Council (CSC) for support and give me the opportunity to study at China.  ... 
doi:10.3390/app6100268 fatcat:evqc5lgssrcwnhroic6a4evccy

Predictive Transmit Antenna Selection with Maximal Ratio Combining

Shiva Prakash, Ian McLoughlin
2009 GLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference  
A prediction scheme is then applied to mitigate against this degradation for the case of a (2,1;2) TAS system, where one of two transmit antenna is selected to communicate with two receive antennae employing  ...  due to the reduction in the number of RF chains required.  ...  Prediction of channel power At instant k, the receiver selects a transmit antenna based on the predicted channel power given by: γ i = Nr j=1 ĥ ij 2 (7) and picks the antenna i corresponding to maximum  ... 
doi:10.1109/glocom.2009.5425217 dblp:conf/globecom/PrakashM09 fatcat:fsea7tn5uvhq7jje2dm66pkpoy

Massive-MIMO- Past, Present and Future: A Review

Piyush Vardhan, Manisha Gupta, Arun Kumar
2016 Indian Journal of Science and Technology  
The review is paying attention on the problems like, getting true channel state information, antenna correlation, channel estimation, signal detection schemes at receiver end, different kind of possible  ...  Findings: It is observed that multiple antenna systems with huge amount of antenna elements at base station are competent to increase data rate by many folds, without requirement of any extra bandwidth  ...  Acknowledgments Heartfelt thanks to the Dept. of electronics and communication, JECRC University, Jaipur, (Rajasthan) for providing the facilities to perform on Massive-MIMO systems.  ... 
doi:10.17485/ijst/2016/v9i48/99891 fatcat:dpgxn2u43rgldlu37ylxirxri4

Channel estimation for spatial modulation

Xiping Wu, Marco Di Renzo, Harald Haas
2013 2013 IEEE 24th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC)  
When compared with CCE, the new method obtains a Signal-to-Noise Ratio (SNR) gain of up to 7.5 dB for medium and high correlations between the transmit antennas.  ...  In addition, we propose an analytical framework to compute the distribution of the CE errors over time-varying fading channels.  ...  ACKNOWLEDGEMENT We gratefully acknowledge support from the European Union's Seventh Framework Programme (FP7) under grant agreement No. 264759 (GREENET Project).  ... 
doi:10.1109/pimrc.2013.6666151 dblp:conf/pimrc/WuRH13 fatcat:7j4eic3za5cgpil5zvyzk6qevi

Channel Estimation for Spatial Modulation

Xiping Wu, Holger Claussen, Marco Di Renzo, Harald Haas
2014 IEEE Transactions on Communications  
When compared with CCE, the new method obtains a Signal-to-Noise Ratio (SNR) gain of up to 7.5 dB for medium and high correlations between the transmit antennas.  ...  In addition, we propose an analytical framework to compute the distribution of the CE errors over time-varying fading channels.  ...  ACKNOWLEDGEMENT We gratefully acknowledge support from the European Union's Seventh Framework Programme (FP7) under grant agreement No. 264759 (GREENET Project).  ... 
doi:10.1109/tcomm.2014.2366750 fatcat:jhuzyonyxjat5ctxt2tcvx4fkm

Performance analysis for high-speed railway distributed antenna systems with imperfect channel state information

Jing Zhao, Jingxian Wu, Pingzhi Fan
2018 EURASIP Journal on Wireless Communications and Networking  
The analytical and simulation results quantify the significant impacts of imperfect CSI on antenna selection for HSR systems in practical applications.  ...  In order to offer a good tradeoff between system performance, cost, and overhead, antenna selection is performed by considering the impacts of both channel estimation errors and noise, such that the antenna  ...  The presence of imperfect CSI is especially detrimental to antenna selection systems, which rely on the CSI to pick the antenna with the best signal-to-noise ratio (SNR).  ... 
doi:10.1186/s13638-018-1297-9 fatcat:sod3bo3yhjdt3he2rfn7g72xle
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