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Feasibility Conditions of Interference Alignment via Two Orthogonal Subcarriers [article]

Stefan Dierks, Gerhard Kramer, Wolfgang Zirwas
2013 arXiv   pre-print
Conditions are derived on line-of-sight channels to ensure the feasibility of interference alignment.  ...  The conditions involve choosing only the spacing between two subcarriers of an orthogonal frequency division multiplexing (OFDM) scheme.  ...  CONCLUSIONS We derived conditions for feasibility of IA via two orthogonal subcarriers. For line-of-sight channels these conditions can be fulfilled by carefully choosing the subcarrier spacing.  ... 
arXiv:1303.5321v1 fatcat:2oyukonbnra5vola2fkgotcnmm

Feasibility conditions of interference alignment via two orthogonal subcarriers

Stefan Dierks, Gerhard Kramer, Wolfgang Zirwas
2013 2013 IEEE International Symposium on Information Theory  
The conditions for line-ofsight channels involve choosing only the spacing between two subcarriers of an orthogonal frequency division multiplexing (OFDM) scheme.  ...  Conditions are derived on the interference channel with single-antenna nodes to achieve maximal degrees-of-freedom with only two symbol extensions.  ...  CONCLUSIONS We derived conditions to achieve maximal DoF with IA via two orthogonal subcarriers.  ... 
doi:10.1109/isit.2013.6620292 dblp:conf/isit/DierksKZ13 fatcat:r32vjqgda5fy3fdo73ezpyzzv4

Distributed Margin Adaptive Resource Allocation in MIMO OFDMA Networks

Mylene Pischella, Jean-Claude Belfiore
2010 IEEE Transactions on Communications  
Index Terms-Distributed resource allocation, margin adaptive problem, MIMO, OFDMA, inter-cell interference.  ...  In the statistical CSIT case, an approximate analytical expression is obtained for the outage capacity, as a function of the SNR and the outage probability.  ...  Two cases are then possible regarding resource allocation: either interference is low enough, and joint transmission of interfering users is performed, or interference is too high, and orthogonal allocation  ... 
doi:10.1109/tcomm.2010.08.080678 fatcat:fznmf5pe3fcglmx5kiqhwlepaq

Impact of pattern reconfigurable antennas on Interference Alignment over measured channels

Rohit Bahl, Nikhil Gulati, Kapil R. Dandekar, Dwight Jaggard
2012 2012 IEEE Globecom Workshops  
However, the non-orthogonality of signal and interference space limits sum capacity performance.  ...  In recent years, it has been shown that concentrating interference and desired signal into separate spaces using Interference Alignment (IA), can achieve the outer bound of the degrees of freedom for the  ...  We can then express this alignment condition using the defined interference vectors as (5-7) .  ... 
doi:10.1109/glocomw.2012.6477634 dblp:conf/globecom/BahlGDJ12 fatcat:lpy3yc6a4zdoxhgti4ol3aurhi

Fair resource allocation for multiuser MIMO communications network

Hsin-Jui Chou, Che-Ju Tsao, Jen-Ming Wu, Jen-Yuan Hsu, Pang-An Ting
2014 2014 IEEE Global Communications Conference  
This paper studies the fairness optimization of dynamic multiuser multicarrier allocation in the cellular downlink of MIMO orthogonal frequency division multiple access (OFDMA) systems.  ...  To solve the optimization problem, an iterative algorithm is proposed to optimize the subcarrier assignment with low complexity.  ...  The optimization problem of maximizing sum rate can be solved by two separate steps: 1) data stream assignment and 2) interuser interference (IUI) Alignment.  ... 
doi:10.1109/glocom.2014.7037418 dblp:conf/globecom/ChouTWHT14 fatcat:gth3ujf32fci5oeai3m2lwvcve

Interference Alignment In Umts Long Term Evolution

Jörg Reitterer, M. Rupp
2011 Zenodo  
Publication in the conference proceedings of EUSIPCO, Barcelona, Spain, 2011  ...  The financial support by the Federal Ministry of Economy, Family and Youth and the National Foundation for Research, Technology and Development is gratefully acknowledged.  ...  CONCLUSION In this paper interference alignment is evaluated in the context of 3GPP UMTS LTE via the Vienna LTE Link Level simulator.  ... 
doi:10.5281/zenodo.42397 fatcat:qnmsq4ifpvhwnnjt7u6ahhjjlu

The Feasibility of Interference Alignment Over Measured MIMO-OFDM Channels

Omar El Ayach, Steven W. Peters, Robert W. Heath
2010 IEEE Transactions on Vehicular Technology  
Interference alignment (IA) has been shown to provide all users of an interference channel with half the capacity achievable in an interference free point-to-point link resulting in linear sum capacity  ...  The linear scaling is achieved by cooperatively precoding transmitted signals to align interference subspaces at the receivers, effectively reducing the number of discernible interferers.  ...  For example, [11] gives feasibility conditions on the number of antennas needed per node, while [12] examines the possibility of applying IA to a two user network with no channel state information  ... 
doi:10.1109/tvt.2010.2082005 fatcat:xdpuhpvag5edvbmiqzmbwzebqq

The Feasibility of Interference Alignment over Measured MIMO-OFDM Channels [article]

Omar El Ayach, Steven W. Peters, Robert W. Heath Jr
2010 arXiv   pre-print
Interference alignment (IA) has been shown to achieve the maximum achievable degrees of freedom in the interference channel.  ...  This paper presents the first experimental study of IA in measured multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) interference channels.  ...  For example, [10] gives feasibility conditions on the number of antennas needed per node, while [11] examines the possibility of applying IA to a two user network with no channel state information  ... 
arXiv:0911.1849v3 fatcat:rtjq7iiqgzddhplywvokltejry

Group-Orthogonal Multicarrier CDMA

X. Cai, S. Zhou, G.B. Giannakis
2004 IEEE Transactions on Communications  
In our group orthogonal multicarrier CDMA (GO-MC-CDMA) scheme, groups of users share a set of subcarriers.  ...  MUI is only present among users in the same group, and is suppressed via multiuser detection, which becomes practically feasible because we assign a small number of users per group.  ...  ACKNOWLEDGMENT The authors would like to thank the anonymous reviewers for their careful reading and critique of the manuscript. Their comments and suggestions improved the presentation of this paper.  ... 
doi:10.1109/tcomm.2003.822174 fatcat:a2jkxewz3jcudd47dpigy6jdnq

Joint user clustering and resource allocation for device-to-device communication underlaying MU-MIMO cellular networks

Qiang Wang, Conglin Lai, Yue Dong, Yuquan Shu, Xiaodong Xu
2015 EURASIP Journal on Wireless Communications and Networking  
Interference alignment (IA) is proposed to better mitigate in-cluster interference compared with a multiplex scheme, and user clustering and resource allocation are jointly investigated using binary-integer  ...  This type of communication can improve spectral efficiency to address future demand, but interference management, user clustering, and resource allocation are three key problems related to resource sharing  ...  It is worth noting that these two conditions are the sufficient but not the necessity conditions of feasible IA in the investigated scenario.  ... 
doi:10.1186/s13638-015-0358-6 fatcat:2spcfdatonaftnck22q3rqewxi

Phase-Aligned Physical-Layer Network Coding in Visible Light Communications

Xun Guan, Qing Yang, Taotao Wang, Chun Kit Calvin Chan
2019 IEEE Photonics Journal  
To further improve the feasibility, we propose a novel phase-aligning method to counter the phase offset among nodes in practical VLC systems.  ...  Experimental results show a throughput improvement of 88.23% by employing the PNC-VLC framework, and the link budget is reduced by 4 dB at a bit error rate of 3.8 × 10 −3 by using the phase-aligning method  ...  Then we present a new phase-align method for VLC-PNC to improve its BER performance under non-ideal channel condition and also analyze the performance of this method.  ... 
doi:10.1109/jphot.2019.2904954 fatcat:t6voqbg2m5bvzdsjbpq2ano4xu

Experimental demonstration of a DSP-based cross-channel interference cancellation technique for application in digital filter multiple access PONs

E. Al-Rawachy, R. P. Giddings, J. M. Tang
2017 Optics Express  
Experimental demonstration of a DSP-based cross-channel interference cancellation technique for application in digital filter multiple access PONs.  ...  It is shown that with one iteration only the CCIC technique can achieve a reduction in individual OFDM subcarrier BERs of more than 1000 times, an increase in transmission capacity by as much as 19 times  ...  TE is therefore the delay which is applied to the received signals to align the actual and estimated interference signals.  ... 
doi:10.1364/oe.25.003850 pmid:28241596 fatcat:3ksi3fvzkrewjol7e7vclqotou

Implementation of a real-time wireless interference alignment network

Jackson W. Massey, Jonathan Starr, Seogoo Lee, Dongwook Lee, Andreas Gerstlauer, Robert W. Heath
2012 2012 Conference Record of the Forty Sixth Asilomar Conference on Signals, Systems and Computers (ASILOMAR)  
Interference alignment (IA) is a cooperative transmission technique for the interference channel.This paper describes two testbeds that implement real-time Multiple-input multiple-output (MIMO) IA for  ...  The testbeds are used to demonstrate the viability of IA, and to compare its robustness with several alternative transmission strategies, such as 2 × 2 MIMO TDMA, in terms of sum-rates.  ...  All of the users send N s streams of data using orthogonal frequency-division multiplexing (OFDM) with N subcarriers.  ... 
doi:10.1109/acssc.2012.6488968 dblp:conf/acssc/MasseySLLGH12 fatcat:56uugf6ynbac7cnv4xesk4vpjq

Practical Interference alignment in the frequency domain for OFDM-based wireless access networks

Adrian Loch, Thomas Nitsche, Alexander Kuehne, Matthias Hollick, Joerg Widmen, Anja Klein
2014 Proceeding of IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks 2014  
In contrast, aligning interference in the frequency domain among multiple subcarriers can also benefit single-antenna OFDMbased access networks.  ...  Interference alignment (IA) is often considered in the spatial domain in combination with MIMO systems.  ...  To solve the aforementioned linear system, two of the four packets need to be aligned.  ... 
doi:10.1109/wowmom.2014.6918922 dblp:conf/wowmom/LochNKHW014 fatcat:5ratb6ihlndo5kwo2zfemt6tgm

Experimental Demonstration of a Real-Time Digital Filter Multiple Access PON with Low Complexity DSP-Based Interference Cancellation

Ehab Al-Rawachy, Roger Philip Giddings, Jianming Tang
2019 Journal of Lightwave Technology  
To combat physical channel frequency response-induced cross channel interference (CCI) between spectrally-overlaid orthogonal channels, a real-time, reconfigurable CCI cancellation (CCIC) function implemented  ...  in the OLT receiver DSP, is demonstrated to significantly improve the DFMA PON performance and robustness in terms of; significant reductions in total channel BERs and individual subcarrier BERs, substantial  ...  Appropriate, fixed, signal scaling and delays are also applied to align the actual and estimated interference.  ... 
doi:10.1109/jlt.2019.2923546 fatcat:wj6bgdw76bb2hkxh3jx7fzda6y
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