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Performance Improvement of Non-Regerative Cooperative Relay Networks with Optimal Power Allocation and Adaptive M-QAM/M-PSK Modulation Over Generalized Fading Channels

Bhuvan Modi, Annamalai A, Olabiyi O, Odejide O
2016 International Journal of Wireless & Mobile Networks  
power allocation policy among collaborating nodes and adaptive M-ary quadrature amplitude modulation (M-QAM)/ M-ary phase shift keying (M-PSK) techniques in generalized wireless fading environments.  ...  KEYWORDS Cooperative diversity, adaptive modulation, optimum power allocation, relay node placement MOTIVATION The increasing demand for wireless communication system in recent years has necessitated a  ...  There has been widespread research on performance analyses of both non-adaptive cooperative diversity systems and adaptive transmission techniques for classical (non-cooperative) wireless networks; however  ... 
doi:10.5121/ijwmn.2016.8301 fatcat:znht3a2jhbhk5obj2vsxvwwe4y

Performance of a Cooperative Network Using Rate Adaptation and Cooperative Combining

Prasanna Kalansuriya, Madushanka Soysa, Chintha Tellambura
2010 2010 IEEE Wireless Communication and Networking Conference  
The approximation is not only an accurate representation of the received SNR, but also amenable to performance analysis. We then derive the probability density function (PDF) of the approximate SNR.  ...  The PDF is used to derive expressions of the parameters required for the performance analysis of rate adaptive transmission, based on the use of a discrete set of modes of square M -ary quadrature amplitude  ...  The probability density function (PDF) of the approximate SNR is derived and is used for the subsequent performance analysis.  ... 
doi:10.1109/wcnc.2010.5506565 dblp:conf/wcnc/KalansuriyaST10 fatcat:nqq7w4z6n5h7baodhu6lrh3tcm

Performance Analysis of Adaptive M-QAM for Rayleigh Fading Cooperative Systems

T. Nechiporenko, K. T. Phan, C. Tellambura, H. H. Nguyen
2008 2008 IEEE International Conference on Communications  
Rayleigh fading environments. The analysis is based on an accurate upper bound on the total effective signal-tonoise ratio SNR at the destination.  ...  The use of constant-power, rate-adaptive M -QAM transmission with an amplify-and-forward cooperative system is proposed.  ...  This makes adaptive techniques based on adaptive M -QAM modulation such as those proposed in [10] , [11] viable. For this reason, adaptive M -QAM is also considered in this paper.  ... 
doi:10.1109/icc.2008.638 dblp:conf/icc/NechiporenkoPTN08 fatcat:fqrbur32zvbjnnvq4bivjbzudy

Cognitive Radio Communications for Vehicular Technology – Wavelet Applications [chapter]

Murroni Maurizio, Popescu Vl
2011 Vehicular Technologies: Increasing Connectivity  
The basic block diagram of an adaptive modulation based cognitive radio system is shown in figure 9 .  ...  Due to this, overlapping features in power spectral density are non-overlapping features in cyclic spectrum.  ...  This chapter is distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike-3.0 License, which permits use, distribution and reproduction for non-commercial purposes, provided  ... 
doi:10.5772/14913 fatcat:jwfirzz6a5ea5hdg7bu4k45xyi

Efficient Symbol Error Rate Analysis of Cooperative Non-Regenerative Relay Systems over Generalized Fading Channels

Oluwatobi Olabiyi
2012 International Journal of Wireless & Mobile Networks  
Our proposed moment generating function (MGF) based analytical framework is also sufficiently general to encapsulate all types of coherent, differentially-coherent and non-coherent digital modulation schemes  ...  In this article, we develop a unified approach to the asymptotic performance analysis of symbol error rates for two-hop cooperative non-regenerative multi-relay networks over a myriad of stochastic channel  ...  ACKNOWLEDGEMENTS This work was supported in part by funding from the US Army Research Office (W911NF-04-2-0054), Clarkson Aerospace, and the National Science Foundation (0931679 and 1040207).  ... 
doi:10.5121/ijwmn.2012.4101 fatcat:yguftfvvvzerrprs5b6g44qgwe

Performance Analysis of the Link-Adaptive Cooperative Amplify-and-Forward Relay Networks with Opportunistic Relaying Strategy

Bhuvan Modi, Olabiyi O, Annamalai A
2016 International Journal of Computer Networks & Communications  
on the new communication paradigm of cooperative relay system.  ...  This paper analyzes the performance of cooperative amplify-and-forward (CAF) relay networks that employ adaptive M-ary quadrature amplitude modulation (M-QAM)/M-ary phase shift keying (M-PSK) digital modulation  ...  ACKNOWLEDGMENT This work is supported in part by funding from the National Science Foundation NSF/HRD 0931679 and the US Air Force Research Laboratory (Contract #FA8750-09-1-0151).  ... 
doi:10.5121/ijcnc.2016.8301 fatcat:o4gn5tvrqrfwrph7wexu34cnqy

A Review for the Adopted Techniques in Low SNR Communication Systems

2020 Iraqi Journal of Computer, Communication, Control and System Engineering  
Finally, the survey throughout this paper recommends some significant techniques that can be used in the analysis and design of successful communication systems in LSNR regimes.  ...  Amongst these topics, the study reviews the most widely utilized modulation techniques in LSNR communication systems such as the On-Off Keying (OOK) and binary PSK schemes.  ...  In [63] , a novel estimation technique for BPSK and QPSK signals is proposed based on non-data aided (NDA) technique.  ... 
doi:10.33103/uot.ijccce.20.1.5 fatcat:rpyjjpsmtfdnbb3pzrhwgqzota

Performance Analysis of Decode and Forward Cooperative Relaying over the Generalized-K Channel

Ali Dziri, Michel Terre, Nidal Nasser
2013 Wireless Engineering and Technology  
In this paper, we analyze the performance of cooperative diversity using adaptive Decode and Forward (DF) relaying over independent but non-necessarily identical flat composite fading channels which include  ...  Depending on the radio propagation environment and the underlying communication scenario, there is a range of statistical multipath fading models available in the literature, such as Rayleigh, Rician,  ...  In [12, 13] , the authors studied the outage and the average error probability of adaptive DF cooperative networks with identical and non-identical Rayleigh fading channels.  ... 
doi:10.4236/wet.2013.42014 fatcat:rmdyw4gcaffznap7abnzc6hz2m

Efficient Analysis of the Ergodic Capacity of Cooperative Non-Regenerative Relay Networks Over Generalized Fading Channels

Bhuvan Modi, Olabiyi O., Annamalai A.
2016 International Journal of Wireless & Mobile Networks  
The proposed frame work based on the novel approximate MGF method is sufficiently general to encapsulate all types of fading environments (especially for the analysis of the mixed fading case)and provides  ...  Three distinct adaptive source transmission policies were considered in our analysis namely: (i) constant power with optimal rate adaptation (ORA); (ii) optimal joint power and rate adaptation (OPRA);  ...  ACKNOWLEDGEMENT This work was supported in part by funding from the Air Force Research Laboratory/Clarkson Aerospace, and the National Science Foundation (0931679 and 1040207).  ... 
doi:10.5121/ijwmn.2016.8503 fatcat:zdhy6tjaxzazhemaqdd7edpzzy

Adaptive Energy Efficient Communications for Hybrid Aerial-Terrestrial Systems [article]

Laurent Reynaud, Sithamparanathan Kandeepan, Karina Gomez, Tinku Rasheed
2013 arXiv   pre-print
The simulation analysis corroborates that the adaptive transmission technique improves the overall energy efficiency of the network.  ...  In this paper, we propose and evaluate a real-time adaptive transmission strategy for dynamic selection of direct and cooperative links based on the channel conditions for improved energy efficiency.  ...  In Fig. 4 we plot the probability distribution function of β based on the results obtained in Fig. 3 .  ... 
arXiv:1208.2825v2 fatcat:q7rqm6cuwfgmdj64jvnufkkv4y

A Novel Chaotic Modulation Scheme in a Cooperative Relaying System

K. Thilagam, K. Jayanthi
2013 International Journal of Computer Applications  
In recent years, the demand for new-generation wireless networks has spurred research on cooperative communication, a powerful physical layer technique to combat fading in wireless relaying scenario.  ...  The simulation results have validated the effectiveness of the proposed scheme by offering better BER performance, minimum outage probability and increased spectral efficiency compared to the non-cooperative  ...  In [1] , the authors discuss the application of adaptive modulation concept to enhance the performance of cooperative techniques and to improve the spectral efficiency of the amplify and forward system  ... 
doi:10.5120/13273-0783 fatcat:ed2pc4xyzrek3ebxyz4pgqhyxi

NeXt generation/dynamic spectrum access/cognitive radio wireless networks: A survey

Ian F. Akyildiz, Won-Yeol Lee, Mehmet C. Vuran, Shantidev Mohanty
2006 Computer Networks  
The novel functionalities and current research challenges of the xG networks are explained in detail.  ...  The influence of these functions on the performance of the upper layer protocols such as routing and transport are investigated and open research issues in these areas are also outlined.  ...  Distinct features of the received signal are extracted using cyclic spectral analysis and represented by both spectral coherent function and spectral correlation density function.  ... 
doi:10.1016/j.comnet.2006.05.001 fatcat:qnrfzg2slvcwzedf4caqocjl4u

Cognitive Radio Networks- Spectrum Sensing

M. Vinod Kumar Reddy, Department of ECE, CVR College of Engineering, Ibrahimpatnam, Hyderabad, India, K. Arun Kumar, Department of ECE, CVR College of Engineering, Ibrahimpatnam, Hyderabad, India
2015 CVR Journal of Science & Technology  
Cognitive radio plays an important role in wireless communication. The spectrum has become a limited resource by ever increasing demand for wireless communications.  ...  Cognitive radios are better solution to the problem of overcrowed and inefficient licensed spectrum.  ...  Analyzing the Spectrum: Spectrum Analysis is based on spectrum sensing which is analyzing the situation of several factors in the external and internal radio environment (such as radio frequency spectrum  ... 
doi:10.32377/cvrjst0806 fatcat:7s3z7cflbze6nawrwo5h2nixim

Closed-form expression for the BER performance in cooperative communication systems with MRC over Rayleigh fading channels

Amer M. Magableh, Mustafa M. Matalgah
2010 Proceedings of the 6th International Wireless Communications and Mobile Computing Conference on ZZZ - IWCMC '10  
terms of bit error rates and outage probability.  ...  Considering an L-Relay nodes AF cooperative network in Rayleigh fading channels employing MRC, closed-form approximate expressions are derived for the bit error rate (BER) of a class of coherent modulation  ...  non-cooperative communication.  ... 
doi:10.1145/1815396.1815490 dblp:conf/iwcmc/MagablehM10a fatcat:rp4fgburazht5ka3qremocaeia

Energy Detection Technique for Spectrum Sensing in Cognitive Radio: A Survey

Mahmood A. Abdulsattar
2012 International Journal of Computer Networks & Communications  
In this paper, a surveyof energy detector over Additive White Gaussian Noise (AWGN), different fading channels for spectrum sensing methodologies in cognitive radio is presented.Theoretical analysis of  ...  Cooperative spectrum sensing and a multiple antenna processing based energy detector receptions are also discussed.  ...  A CR transceiver is senseradio environment and capable of adapting its physical layer parameters according to the environment.  ... 
doi:10.5121/ijcnc.2012.4514 fatcat:ceng32wmeba27azeowmwm57dyq
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