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An efficient adaptive distributed space-time coding scheme for cooperative relaying

J. Abouei, H. Bagheri, A. Khandani
2009 IEEE Transactions on Wireless Communications  
In addition, a hybrid amplify-and-forward/detect-and-forward scheme is proposed for the case that the quality of the source-relay link is good.  ...  Finally, the robustness of the proposed scheme in the presence of channel estimation errors is numerically evaluated.  ...  This new diversity approach, referred to as the cooperative relaying, has attracted considerable attention in wireless networks in recent years [1] - [3] .  ... 
doi:10.1109/twc.2009.081615 fatcat:scbc24psmnab3nlsyieopz5x24

Interference Mitigation in Cooperative SFBC-OFDM

D. Sreedhar, A. Chockalingam
2008 EURASIP Journal on Advances in Signal Processing  
In cooperative SFBC-OFDM networks that employ DF protocol, (i), intersymbol interference (ISI) occurs at the destination due to violation of the "quasistatic" assumption because of the frequency selectivity  ...  In cooperative networks using SFBC-OFDM, however, this full-diversity attribute of the phase-compensated AF protocol is lost due to frequency selectivity and imperfect carrier synchronization on the relay-to-destination  ...  Without any effort to handle this interference, the performance of cooperative OFDM may end up being worse than that of OFDM without cooperation, particularly when the synchronization errors (in terms  ... 
doi:10.1155/2008/125735 fatcat:36c5yfhu3vewvfrzvjqhduyyoe

Dispensing with Channel Estimation: Differentially Modulated Cooperative Wireless Communications

Li Wang, Lajos Hanzo
2011 IEEE Communications Surveys and Tutorials  
In order to stimulate further research on differentially modulated cooperative systems, a number of fundamental challenges encountered in their practical implementations are addressed, including the time-variant-channel-induced  ...  Our investigations demonstrate the quantitative benefits of cooperative wireless networks both from a pure capacity perspective as well as from a practical system design perspective.  ...  The concept of user cooperation has been first proposed in [19, 20] for a twouser cooperative CDMA system, where orthogonal codes are employed by the active users in order to avoid multiple access interference  ... 
doi:10.1109/surv.2011.081611.00138 fatcat:vx6k4zdqanb4nmbyfxnjsdu6kq

OFDM Communication with Cooperative Relays [chapter]

Hao Lu, Homayoun Nikookar, Tao Xu
2010 Communications and Networking  
Although DF relaying has the advantage over AF relaying in reducing the effects of noise and interference at the relay, it entails the possibility of forwarding erroneously detected signals to the destination  ...  Adopting this point of view, nodes in the network can cooperate together for a distributed transmission and processing of information. The cooperating node acts as a relay node for the source node.  ...  Then, we will show how to use the linear property of , Tr H to achieve full spatial diversity in the cooperative system. Consequently, (27) can be rewritten as ,,, , H rP r P r T r N r r  ... 
doi:10.5772/10157 fatcat:vv6nhwjdcbaoreskvhhwvsopnu

A Comprehensive Review on Spectrum Management, Security and Energy-Efficient Cognitive Radio Networks

Shyleshchandra Gudihatti, S. H., Venugopal K.
2019 International Journal of Computer Applications  
In addition, we study the energy efficient routing techniques like network optimization frameworks in cooperative networks, protocols and different types of attack issues, approaches for handling the secure  ...  Cognitive Radio Network (CRN) is an evident optimal solution in alleviating the challenges of spectrum unused potentially in wireless networks.  ...  ., [59] proposed a joint frequency and routing approach that uses prediction of interference for CR and data rate transmission to reduce end-to-end delay of the SU.  ... 
doi:10.5120/ijca2019918371 fatcat:d5yvihq4zfhvxbz4lml7bruxm4

Distributed one bit feedback extended orthogonal space time coding based on selection of cyclic rotation for cooperative relay networks

A. M. Elazreg, J. A. Chambers
2011 2011 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)  
In addition, the transmission rate over each hop in the network is unity and full cooperative diversity is obtained by the approach.  ...  In this scheme, only one-bit of feedback is used to determine the transmission phase terms applied to the symbols from the antennas of each relay nodes.  ...  It is well known that the presence of the channel dependent interference gf may be negative, this leads to cooperative diversity loss.  ... 
doi:10.1109/icassp.2011.5947100 dblp:conf/icassp/ElazregC11 fatcat:pj6whirrl5hyvo6je3fh5lxd6u

Multiple-Symbol Joint Signal Processing for Differentially Encoded Single- and Multi-Carrier Communications: Principles, Designs and Applications

Li Wang, Li Li, Chao Xu, Dandan Liang, Soon Xin Ng, Lajos Hanzo
2014 IEEE Communications Surveys and Tutorials  
to its coherent detection aided counterpart.  ...  transmissions, such as their applications in high-order differentially modulated systems and in differential interference suppression of spatial-division multiplexing/multiple access scenarios.  ...  Apart from the above obstacles in the way of achieving multiple-antenna-aided diversity gains, wireless cellular networks aim for improving the coverage, capacity or the quality of end-user experience  ... 
doi:10.1109/surv.2013.081313.00218 fatcat:lybolh7wtrfpdje2eultynvow4

Multiple-antenna techniques for wireless communications - a comprehensive literature survey

Jan Mietzner, Robert Schober, Lutz Lampe, Wolfgang Gerstacker, Peter Hoeher
2009 IEEE Communications Surveys and Tutorials  
Multiple antennas can be utilized in order to accomplish a multiplexing gain, a diversity gain, or an antenna gain, thus enhancing the bit rate, the error performance, or the signal-to-noise-plus-interference  ...  To this end, the last ten years of research efforts are recapitulated, with focus on spatial multiplexing and spatial diversity techniques.  ...  For example, spatial multiplexing techniques can also accomplish a diversity gain, e.g., if an optimum receiver in the sense of maximum-likelihood (ML) detection is employed.  ... 
doi:10.1109/surv.2009.090207 fatcat:ki2ponfnp5ditjjbp7bsx5ncfm

Timing and carrier synchronization in wireless communication systems: a survey and classification of research in the last 5 years

Ali A. Nasir, Salman Durrani, Hani Mehrpouyan, Steven D. Blostein, Rodney A. Kennedy
2016 EURASIP Journal on Wireless Communications and Networking  
synchronization in single-input-single-output (SISO), multiple-input-multiple-output (MIMO), cooperative relaying, and multiuser/multicell interference networks.  ...  Timing synchronization is the process by which a receiver node determines the correct instants of time at which to sample the incoming signal.  ...  In the context of interweave cognitive networks, SUs sense the spectrum to detect the presence or absence of PUs and use the unoccupied bands while maintaining a predefined probability of missed detection  ... 
doi:10.1186/s13638-016-0670-9 fatcat:xqzvzx4trrgdnbw2sde5gjoisa

Enabling Cooperative Relaying VANET Clouds Over LTE-A Networks

Mohamed F. Feteiha, Hossam S. Hassanein
2015 IEEE Transactions on Vehicular Technology  
Hence, we propose a precoded cooperative transmission technique to extract the underlying rich multipath-Doppler-spatial diversity, which is a relay selection scheme to take advantage of the potentially  ...  We investigate the performance of a transmission scheme over a Long-Term Evolution-Advanced (LTE-A) network where vehicles act as relaying cooperating terminals for a downlink session between a base station  ...  the sake of presentation, and the pdf for the end-to-end SNR is fγ(x) = fγ sd (x) * fγ b (x).  ... 
doi:10.1109/tvt.2014.2329880 fatcat:gswmqfie75h7phkd22k64boux4

A Survey on Design and Performance of Higher-Order QAM Constellations [article]

Praveen Kumar Singya, Parvez Shaik, Nagendra Kumar, Vimal Bhatia
2020 arXiv   pre-print
With this, it can be claimed that the use of the HQAM in various wireless communication systems and standards can further improve the performance targeted for beyond 5G wireless communication systems.  ...  The increasing demand for high data-rates has further encouraged the research towards more compact 2D constellations which lead to hexagonal lattice structure based constellations, referred to as hexagonal  ...  In cooperative relaying, the end-to-end information transmission takes place through indirect links (relay nodes) by enabling the cooperation with the relays employed.  ... 
arXiv:2004.14708v1 fatcat:okupeb57cnaa3kjf3gyzhludde

A Survey on Beamforming Techniques for Wireless MIMO Relay Networks

Demosthenes Vouyioukas
2013 International Journal of Antennas and Propagation  
relaying, degrees of freedom, diversity issues, and spectral efficiency, in cooperative and opportunistic systems.  ...  Thus, in a multitier network, the demand for high-speed and interference-free transmission and reception is inevitable.  ...  Conflict of Interests The author declares that there is no conflict of interests regarding the publication of this paper.  ... 
doi:10.1155/2013/745018 fatcat:vclhrye455aedj3fsin43j3cqm

A Systematic Review on NOMA Variants for 5G and Beyond

Ishan Budhiraja, Neeraj Kumar, Sudhanshu Tyagi, Sudeep Tanwar, Zhu Han, Doug Young Suh, MD. Jalil Piran
2021 IEEE Access  
Over the last few years, interference has been a major hurdle for successfully implementing various end-user applications in the fifth-generation (5G) of wireless networks.  ...  However, interference persists, keeping given quality of service (QoS) provision to end-users for different 5G applications.  ...  SUs using multi-user diversity to cooperate between the primary and secondary networks.  ... 
doi:10.1109/access.2021.3081601 fatcat:mzmmr3km5zehhh3fnupyelfo3e

Satellite Communications: Research Trends and Open Issues

A. Vaneli-Corali, G. E. Corazza, G. K. Karagiannidis, P. T. Mathiopoulos, D. S. Michalopoulos, C. Mosquera, S. Papaharalabos, S. Scalise
2007 2007 International Workshop on Satellite and Space Communications  
In the DVB forum, after the publication of the DVB-S2 standard and the approval of the DVB-SH specifica-  ...  environments (from broadcast to fixed terminals, to broadband mobile satellite access), we address scodin scm,prolayrorte rocreinFC physical layer aspects related to satellite communications in the smart  ...  Wornell, Distributed space-time coded systems tends to align withthatofterrestrialcomprotocol for exploiting cooperative diversity in wireless networks, IEEE systems tends to align with that of terrestrial  ... 
doi:10.1109/iwssc.2007.4409393 fatcat:nmed46rrandezmec3bssr5jun4

Hybrid Automatic-Repeat-reQuest Systems for Cooperative Wireless Communications

Hoang Anh Ngo, Lajos Hanzo
2014 IEEE Communications Surveys and Tutorials  
diversity provided by user cooperation in the presence of inter-user interference. 2005 Azarian at al  ...  in a wireline-based network due to the effects of fading and interference.  ... 
doi:10.1109/surv.2013.071913.00073 fatcat:ct2gqy36i5fuzbnnarvk3j6jiq
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