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Further results on selective multiuser diversity

Lin Yang, Mohamed-Slim Alouini, David Gesbert
2004 Proceedings of the 7th ACM international symposium on Modeling, analysis and simulation of wireless and mobile systems - MSWiM '04  
Numerical examples confirm that selective multiuser diversity reduces dramatically the feedback load but maintains a good portion of multiuser diversity gain.  ...  In this paper we study the performance of a recently proposed scheduling technique, known as selective multiuser diversity scheme, when the users in the system have unequal average signal-to-noise ratios  ...  In [4] , selective multiuser diversity scheduling was proposed to reduce the amount of total feedback while maintaining a good portion of multiuser diversity gain.  ... 
doi:10.1145/1023663.1023671 dblp:conf/mswim/YangAG04 fatcat:ogxpjrcw2zag5lehdmbi3uywzm

A unified capacity analysis for wireless systems with joint multiuser scheduling and antenna diversity in Nakagami fading channels

C.-J. Chen, Li-Chun Wang
2006 IEEE Transactions on Communications  
Our analytical results lead to the following four observations regarding the interplay of multiuser scheduling and antenna diversity.  ...  Third, the boosted array gain of the MRT/MRC scheme can compensate the detrimental impact of the reduced amount of fading gain on multiuser scheduling, thereby resulting in greater capacity than the ST  ...  We further suggest three parameters: array gain; amount of fading gain; and selection order to assess the effect of applying different antenna diversity schemes on top of the multiuser scheduling system  ... 
doi:10.1109/tcomm.2005.863778 fatcat:rek4cylpsnaiph7ehwo5iuyaki

A unified capacity analysis for wireless systems with joint antenna and multiuser diversity in Nakagami fading channels

Chiung-Jang Chen, Li-Chun Wang
2004 2004 IEEE International Conference on Communications (IEEE Cat. No.04CH37577)  
Our analytical results lead to the following four observations regarding the interplay of multiuser scheduling and antenna diversity.  ...  Third, the boosted array gain of the MRT/MRC scheme can compensate the detrimental impact of the reduced amount of fading gain on multiuser scheduling, thereby resulting in greater capacity than the ST  ...  We further suggest three parameters: array gain; amount of fading gain; and selection order to assess the effect of applying different antenna diversity schemes on top of the multiuser scheduling system  ... 
doi:10.1109/icc.2004.1313199 dblp:conf/icc/ChenW04 fatcat:gm6juy53r5felkltkf4lltra6y

Cooperative Spectrum Sensing In Cognitive Radio Networks Using Distinct Coding Techniques

R. saranya, Mrs K.Shanthalakshmi
2014 IOSR Journal of Electronics and Communication Engineering  
For a comparison purpose, an analysis of the transmit antenna selection scheme is also presented. Finally, some selected numerical results are presented to corroborate the proposed analysis.  ...  This paper considers a multiuser spectrum sharing(SS) system operating in a Rayleigh fading environment and in which every node is equipped with multiple antennas.  ...  As expected, the simulation results coincide with the analytical ones, and the multiuser diversity gain can further improve the system performance.  ... 
doi:10.9790/2834-09154852 fatcat:kl7vsrwfuvba7bvbuzmszcob4a

Multiuser diversity for MIMO-Y channel: Max-min selection and diversity analysis

Hui Gao, Chau Yuen, Himal A. Suraweera, Tiejun Lv
2013 2013 IEEE International Conference on Communications (ICC)  
The impacts of user configurations on the multiuser diversity gains are investigated by theoretical bounds as well as numerical results.  ...  In particular, a Max-Min user selection is proposed, which aims to harvest the multiuser diversity gain for reliable transmission in the MIMO-Y channel.  ...  These simulation results also validate our theoretical analysis on the scalability of asymmetric multiuser diversity gain.  ... 
doi:10.1109/icc.2013.6655519 dblp:conf/icc/GaoYSL13 fatcat:wk5cnywmk5gztnf3uroqw7kh5a

Performance Analysis for Partial Feedback Downlink MIMO with Unitary Codebook Beamforming for LTE

M. Nicolaou, A. Doufexi, S. Armour, Y. Sun
2009 2009 IEEE International Conference on Communications Workshops  
, resulting in a further increase in uplink overhead.  The Base Station makes a decision on the optimum precoding matrix and performs resource allocation based on received CQI values.  Partial Feedback  ...  matrices resulting in a Mfold increase in uplink feedback overhead.  MU-MIMO requires CQI values to be fed back for each of the spatial layer of each precoding matrix, resulting in a further increase  ... 
doi:10.1109/iccw.2009.5208022 fatcat:luxmqrwdkzcr5phh4gtg73yfgq

Antenna-diversity-assisted genetic-algorithm-based multiuser detection schemes for synchronous CDMA systems

K. Yen, L. Hanzo
2003 IEEE Transactions on Communications  
A spatial diversity reception assisted multiuser code-division multiple-access detector based on genetic algorithms (GAs) is proposed.  ...  In our first approach, the so-called individuals of the GA are selected for further exploitation, based purely on the sum of their corresponding figures of merit evaluated for the individual antennas.  ...  SIMULATION RESULTS In this section, computer simulations are presented based on evaluating the BER performance of the GA-based multiuser detector employing the above two GA-based individual-selection strategies  ... 
doi:10.1109/tcomm.2003.809755 fatcat:jnu7doavhjhobexwko6ky2jonm

Multiuser Diversity in Wireless Networks: A Diversity-Multiplexing Perspective

Kaushik Josiam, Dinesh Rajan
2007 2007 41st Annual Conference on Information Sciences and Systems  
The multiuser diversity gains in all three channels are obtained without explicit cooperation between users.  ...  We show that for the multiple access channel with K users, a feedback of log K bits is sufficient to maximize the multiuser diversity gain.  ...  Additionally, CSIT was shown to improve the diversity gain due to the multiple users themselves, a gain termed multiuser diversity.  ... 
doi:10.1109/ciss.2007.4298340 dblp:conf/ciss/JosiamR07 fatcat:uupgqj4ljfghploemzy5cisl74

A Selective Cluster Index Scheduling Method in OFDMA

Marios Nicolaou, Angela Doufexi, Simon Armour
2008 2008 IEEE 68th Vehicular Technology Conference  
A scheduler exploiting Multiuser Diversity is required to have access to Channel State Information (CSI), at least at the rate at which the channel is changing, i.e. depends on the coherence time of the  ...  Due to the requirement of SNR knowledge across the frequency domain, for OFDMA systems exploiting Multiuser Diversity, overall capacity quickly reaches bottleneck point, at which the entire uplink channel  ...  A scheduler employing Multiuser Diversity does not schedule user on weak clusters.  ... 
doi:10.1109/vetecf.2008.460 dblp:conf/vtc/NicolaouDA08a fatcat:em4fee4vpncs3d4uc4n7ru2kim

Impact of User Selection Criteria on Performance of MIMO Detectors in Multiuser Systems

Jinho Choi, Fumiyuki Adachi
2010 2010 IEEE 71st Vehicular Technology Conference  
We also show that the maximum likelihood (ML) and even some low complexity suboptimal detectors (based on the lattice reduction (LR)) can achieve a full multiuser and receive diversity when the user selection  ...  It is shown that the user selection criterion plays a crucial role in exploiting both multiuser and receive (or spatial) diversity.  ...  SIMULATION RESULTS In this section, we present simulation results to see the diversity gain from the multiuser diversity and MIMO systems.  ... 
doi:10.1109/vetecs.2010.5493829 dblp:conf/vtc/ChoiA10 fatcat:i7sdj5rt3fgvxnicmtl352txfa

The impact of multiuser diversity on space-time block coding

R. Gozali, R.M. Buehrer, B.D. Woerner
2003 IEEE Communications Letters  
In this letter, analytic performance results are derived for space-time block coding paired with multiuser diversity.  ...  Using a scoring function at the BS, time resources are allocated to the user with the best instantaneous effective signal-to-noise ratio (SNR), facilitating a multiuser diversity mechanism.  ...  Natural questions are therefore: 1) How does multiuser diversity enhance performance further? and 2) Is multiuser diversity mechanism equivalent to spatial diversity?  ... 
doi:10.1109/lcomm.2003.812182 fatcat:jnb4o3g6enbdlceciyoz3nvfhu

Performance of Multiuser Transmit Diversity in Spatially Correlated Channels

Haelyong Kim, Namshik Kim, Wan Choi, Hyuncheol Park
2010 IEEE Communications Letters  
Our analytical and numerical results verify a positive effect of spatial correlation on multiuser diversity in terms of ergodic capacity.  ...  This paper investigates the performance of an Alamouti coding based transmit diversity scheme with multiuser maxscheduling in spatially correlated channels.  ...  INTRODUCTION M ULTIUSER diversity is realized by selecting the user with the highest channel gain through multiuser scheduling.  ... 
doi:10.1109/lcomm.2010.080410.100909 fatcat:faojly2udfdvppzxj6tqqb7zyu

User Selection Criteria for Multiuser Systems With Optimal and Suboptimal LR Based Detectors

Jinho Choi, Fumiyuki Adachi
2010 IEEE Transactions on Signal Processing  
We also show that the ML and even some low complexity suboptimal detectors (based on the lattice reduction (LR)) can achieve a full multiuser and receive diversity when the user selection criterion is  ...  It is shown that the user selection criterion plays a crucial role in exploiting both multiuser and receive (or spatial) diversity.  ...  SIMULATION RESULTS In this section, we present simulation results to see the diversity gain from the multiuser diversity and MIMO systems.  ... 
doi:10.1109/tsp.2010.2053361 fatcat:bist5zagcbhcnepav6d6ucxs3q

Scheduling Gain in Spatial Diversity Systems: Asymptotic Analysis

Huaiyu Dai, Quan Zhou
2006 2006 IEEE International Symposium on Information Theory  
In this paper, further in-depth asymptotic analysis on the interaction between spatial diversity and multiuser diversity in wireless networks is given, following our recent work [Zhou and Dai, ICC06].  ...  Our results are general enough to cover many practical scenarios of interest.  ...  CONCLUSION AND FUTURE WORK This paper presents further in-depth asymptotic analysis on the interaction between spatial diversity and multiuser diversity in wireless networks.  ... 
doi:10.1109/isit.2006.262040 dblp:conf/isit/Dai006 fatcat:ofyqswgfnnasje7oly4xhwy26e

On the Multiuser Diversity of Relay-Aided Downlink Systems Using Reduced Feedback

Yong-Up Jang, Won-Yong Shin
2014 The Scientific World Journal  
Based on the analysis, we propose afeedback-efficienttwo-step multiuser scheduling algorithm: the transmission mode selection followed by the user selection that only needs a partial feedback for instantaneous  ...  We also analyze theaverage SNRcondition such that the multiuser diversity gain is fully exploited for two-hop transmission.  ...  Unlike the asymptotic result for one-hop transmission, it is shown that full multiuser diversity gain is not always guaranteed for two-hop transmission case.  ... 
doi:10.1155/2014/857540 pmid:25436232 pmcid:PMC4241708 fatcat:hissxo7xv5gkxapapqqcklhh3e
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