AIT Community / Faculty / Research Scientists / George C. Alexandropoulos

CONTACT INFORMATION George C. Alexandropoulos / Researcher Athens Information Technology 19.5 Km Markopoulo Avenue 19002 Peania, Attiki, Greece Phone: (+) 30-210-668-2801 Mob: (+) 30-694-469-2141  e-mail: alexandg at ait dot gr URL: www.alexandropoulos.info

SUMMARY

Dr. George C. Alexandropoulos is a Researcher at the Athens Information Technology (AIT) and a member of the Broadband Wireless and Sensor Networks research team. He was born in Athens, Greece in 1980. He received the Diploma degree in Computer Engineering and Informatics, the M.A.Sc. degree (with distinction) in Signal Processing and Communications, and the Ph.D. degree in Wireless Communications from the Computer Engineering and Informatics Department (CEID), School of Engineering (SE), University of Patras (UoP), Rio-Patras, Greece in 2003, 2005, and 2010, respectively. From 2001-2010, he has been a research fellow at the Signal Processing and Communications Laboratory, CEID, SE, UoP, Rio-Patras, Greece. During 2006-2010, he was with the National Centre for Scientific Research–“Demokritos,” Athens, Greece, where he was a Ph.D. scholar at the Wireless Communications Laboratory of the Institute of Informatics and Telecommunications. From 2007-2011, he has been affiliated with the National Observatory of Athens, Institute for Space Applications and Remote Sensing, Athens, Greece, where he has participated in several national and European R&D projects. During the summer semester of 2011, he has been an Adjunct Lecturer at the Department of Telecommunications Science and Technology of the University of Peloponnese, Tripolis, Greece.

His research interests include cooperative and cognitive radio systems, fading channels, interference alignment, MIMO techniques, and signal processing for communications. He acts as a reviewer for several international journals and conferences, and he is a member of the IEEE, the IEEE Communications Society, and the Technical Chamber of Greece. Dr. G. C. Alexandropoulos has received a postgraduate scholarship from the Operational Programme for Education and Initial Vocational Training II, Ministry of Education, Lifelong Learning, and Religious Affairs, Greek Republic, a student travel grant for the IEEE GLOBECOM 2010 in Miami, Florida, USA, and the best Ph.D. thesis award 2010 by the Informatics and Telematics Institute, Thessaloniki, Greece.

EDUCATION 

Ph.D. in Wireless Communications, Computer Engineering and Informatics Department, School of Engineering, University of Patras, Rio-Patras, Greece, 2010.
Thesis Topic: Performance Study of Space Diversity Receivers over Correlated Fading Channels

M.A.Sc. in Signal and Communications Processing Systems, Computer Engineering and Informatics Department, School of Engineering, University of Patras, Rio-Patras, Greece, 2006.
Thesis Topic: Development and Implementation of Dominant Source Localization and Tracking Techniques in Randomly Distributed Sensor Networks

Diploma degree in Computer Engineering & Informatics, Computer Engineering and Informatics Department, School of Engineering, University of Patras, Rio-Patras, Greece, 2003.
Thesis Topic: Implementation of ADPCM Source Coding in the TMS320C6711 Digital Signal Processor

• Best award 2010 for a Ph.D. thesis conducted in a Greek university by the Informatics and Telematics Institute, Thessaloniki, Greece.
• Student travel grant for IEEE Global Communications Conference, Miami, Florida, USA, 2010.
• Biography inclusion in the Who’s Who in the World magazine, edition 2010.
• Scholar of the National Centre for Scientific Research–“Demokritos,” Institute of Informatics and Telecommunications, Athens, Greece for Ph.D. dissertation.
• Ranked 2nd in the M.A.Sc. program Signal and Communications Processing Systems: Theory, Implementations and Applications, University of Patras, April 2005.
• Scholar of the Operational Program for Education and Initial Vocational Training II, Ministry of Education, Lifelong Learning, and Religious Affairs, Greek Republic, for M.A.Sc. studies.
• Certificates of excellence and top-ranked student at Gymnasium and Unified Lyceum, Ministry of Education, Lifelong Learning, and Religious Affairs, Greek Republic, 1992 till 1998.

• Jan. 2001 – Dec. 2010: Research Assistant, Signal Processing & Communications Laboratory, Computer Engineering and Informatics Department, School of Engineering, University of Patras, Rio-Patras, Greece. Participation in the ‘‘Reclamation of Syllabus’’ project.
• May 2006 – May 2010: Research Assistant, Wireless Communications Laboratory, Institute of Informatics and Telecommunications, National Centre for Scientific Research–“Demokritos,” Athens, Greece. Participation in the ‘‘Antenna Centre of Excellence 2’’ project.
• Jan. 2007 – Jan. 2011: Research Affiliate, Institute for Space Applications and Remote Sensing, National Observatory of Athens, Athens, Greece. Participation in the OPCE II, SatNeX II and NEWCOM++ projects.
• Feb. 2011 – present: Patents Consultant, Pappas IP Law Office, Athens, Greece. Specialization in patent applications in the field of electronics and computers.
• Apr. 2011 – present: Researcher, Broadband Wireless and Sensor Networks Laboratory, Athens Information Technology, Athens, Greece. Participation in the HIATUS project.

• Sep. 2003 – Jun. 2004: Teaching Assistant, Computer Engineering and Informatics Department, School of Engineering, University of Patras, Rio-Patras, Greece. Laboratory Courses: Digital Communications and Digital Image Processing and Analysis.
• Feb. 2007 – Jun. 2008 and Sep. 2010 – Mar. 2011: Instructor in Information Technology, Organization for Vocational Education and Training, Athens, Greece. Courses: Introduction to Informatics, Computers in Practice and Multimedia Technologies.
• Summer Semester 2011: Adjunct Lecturer, Department of Telecommunications Science and Technology, University of Peloponnese, Tripolis, Greece. Course: Logic Design.
• September 2011: Teaching Assistant, Department of Computer Engineering, Athens Information Technology, Athens, Greece. Preparatory Courses: Analytical Geometry, Complex Numbers, Probabilities.
• Summer Semester 2012: Teaching Assistant, Department of Computer Engineering, Athens Information Technology, Athens, Greece. Course: Mathematics 2A (Linear Algebra).

• Adaptive signal processing
• Adaptive modulation and coding
• Cooperative networks, multicell cooperation
• Digital signal processors programming
• Interference alignment
• Multiple-input multiple-output systems, diversity receivers
• Fading modeling, performance analysis over fading and shadowing channels 
• Signal processing for communications
• Source localization in wireless sensor networks

• 2005: Member of the Technical Chamber of Greece
• 2007: IEEE Student Member
• 2009: Member of the Technical Program Committee for the IEEE International Conference on Wireless Communications and Signal Processing (WCSP) 2009
• 2010: IEEE Member
• 2010: IEEE Communications Society Member
• 2011: Member of the Editorial Advisory Board of Recent Patents on Telecommunications, Bentham Science Publishers
• 2012: IEEE Signal Processing Society Member

• Journals: IEEE Transactions on Communications, IEEE Transactions on Wireless Communications, IEEE Transactions on Signal Processing, IEEE Transactions on Vehicular Technology, IEEE Communications Letters, IEEE Signal Processing Letters, IET Communications and several other international journals
• Conferences: IEEE International Conference on Communications (ICC), IEEE Global Communications Conference (GLOBECOM), IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), IEEE Vehicular Technology Conference (VTC), IEEE International Workshop on Signal Processing Advances for Wireless Communications (SPAWC) and several other international conferences

PUBLICATIONS

Journal Publications

1. G. C. Alexandropoulos, N. C. Sagias, and K. Berberidis, "On the multivariate Weibull fading model with arbitrary correlation matrix," IEEE Antennas and Wireless Propagation Letters, vol. 6, pp. 93-95, 2007.
   
2. G. C. Alexandropoulos, N. C. Sagias, F. I. Lazarakis, and K. Berberidis, "New results for the multivariate Nakagami-m fading model with arbitrary correlation matrix and applications," IEEE Transactions on Wireless Communications, vol. 8, no. 1, pp. 245-255, January 2009.
   
3. G. C. Alexandropoulos, P. T. Mathiopoulos, and N. C. Sagias, "Switch-and-examine diversity over arbitrary correlated Nakagami-m fading channels," IEEE Transactions on Vehicular Technology, vol. 59, no.4, pp. 2080-2087, May 2010.
   
4. G. C. Alexandropoulos, A. Papadogiannis, and K. Berberidis, "Performance analysis of cooperative networks with relay selection over Nakagami-m fading channels," IEEE Signal Processing Letters, vol. 17, no.5, pp. 441-444, May 2010.
   
5. G. C. Alexandropoulos and P. T. Mathiopoulos, "Performance evaluation of selection diversity receivers over arbitrarily correlated generalized Gamma fading channels," IET Communications, vol. 4, no. 10, pp. 1253-1265, June 2010.
   
6. T. Q. Duong, G. C. Alexandropoulos, T. A. Tsiftsis, and H.-J. Zepernick, "Outage probability of MIMO AF relay networks over Nakagami-m fading channels," Electronics Letters, vol. 46, no. 17, pp. 1229-1231, August 2010.
   
7. K. P. Peppas, G. C. Alexandropoulos, C. K. Datsikas, and F. I. Lazarakis, "The multivariate Gamma-Gamma distribution with exponential correlation and its applications in RF and optical wireless communications," IET Microwaves, Antennas & Propagation, vol. 5, no. 3, pp. 364–371, February 2011.
   
8. T. Q. Duong, G. C. Alexandropoulos, H.-J. Zepernick, and T. A. Tsiftsis, "Orthogonal space-time block codes with CSI-assisted amplify-and-forward relaying in correlated Nakagami-m fading channels," IEEE Transactions on Vehicular Technology, vol. 60, no. 3, pp. 882–889, March 2011.
   
9. L. Jacobs, G. C. Alexandropoulos, M. Moeneclaey, H. Bruneel, and P. T. Mathiopoulos, "Analysis and efficient evaluation of the BER of OSTBCs with imperfect channel estimation in arbitrarily correlated fading channels," IEEE Transactions on Signal Processing, vol. 59, no. 6, pp. 2720–2733, June 2011.
   
10. T. Q. Duong, V. N. Q. Bao, G. C. Alexandropoulos, H.-J. Zepernick, "Cooperative spectrum sharing networks with AF relay and selection diversity," Electronics Letters, vol. 47, no. 20, pp. 1149–1151, September 2011.
    
11. G. C. Alexandropoulos, A. Papadogiannis, and P. C. Sofotasios, "A comparative study of relaying schemes with decode-and-forward over Nakagami-m fading channels," Journal of Computer Networks and Communications, vol. 2011, Article ID 560528, 14 pages, 2011.
    
12. A. Papadogiannis, G. C. Alexandropoulos, A. G. Burr, and D. Grace, "Bringing mobile relays for wireless access networks into practice– Learning when to relay," IET Communications, accepted, 2011.
    
13. T. Q. Duong, V. N. Q. Bao, H. Tran, G. C. Alexandropoulos, and H.-J. Zepernick, "Effect of primary networks on the performance of spectrum sharing AF relaying," Electronics Letters, vol. 48, no. 1, pp. 25–27, January 2012.
    
14. M. Matthaiou, G. C. Alexandropoulos, H. Q. Ngo, and E. G. Larsson, "Analytic framework for the effective rate of MISO fading channels," IEEE Transactions on Communications, accepted, 2012.
    
15. P. C. Sofotasios, G. C. Alexandropoulos, A. Papadogiannis, T. Q. Duong, and S. Freear, "Error probability of DF relay selection: On the sensitivity of the Nakagami fading parameter," ETRI Journal, under review, 2012.
    
16. P. C. Sofotasios, A. Papadogiannis, G. C. Alexandropoulos, and S. Freear, "Performance evaluation of decode and forward relay selection in arbitrary Nakagami-m fading," Journal of the Franklin Institute, under review, 2012.
    
17. K. P. Peppas, G. C. Alexandropoulos, and P. T. Mathiopoulos, "Dual-hop AF relaying systems over mixed η-μ and κ-μ fading channels," IEEE Transactions on Vehicular Technology, under review, 2012.

Conference Publications

1. C. K. Datsikas, G. S. Tombras, N. C. Sagias, F. I. Lazarakis, G. C. Alexandropoulos, A. A. Alexandridis, and K. Dangakis, "Dual-hop relaying networks over Nakagami-m fading channels," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Athens, Greece, 3-7 September 2007, pp. 1-4.
   
2. G. C. Alexandropoulos, K. Berberidis, N. C. Sagias, F. I. Lazarakis, C. K. Datsikas, A. A. Alexandridis, and K. Dangakis, "On the sum of squared Rayleigh variates and applications to maximal-ratio diversity," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Athens, Greece, 3-7 September 2007, pp. 1-5.
   
3. G. C. Alexandropoulos, K. Berberidis, N. C. Sagias, F. I. Lazarakis, A. A. Alexandridis, and K. Dangakis, "Householder-matrices based analysis of SC receivers over Rayleigh fading channels with arbitrary correlation," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Athens, Greece, 3-7 September 2007, pp. 1-5.
   
4. G. C. Alexandropoulos, N. C. Sagias, F. I. Lazarakis, and K. Berberidis, "New results on SC and MRC over Nakagami-m fading channels with arbitrary correlation matrix," in Proc. IEEE Global Communications Conference, Washington D.C., USA, 26-30 November 2007, pp. 1551-1555.
   
5. L. Jacobs, G. C. Alexandropoulos, M. Moeneclaey, and P. T. Mathiopoulos, "BER of MRC for M-QAM with imperfect channel estimation over correlated Nakagami-m fading," in Proc. Newcom++/ACoRN Joint Workshop, Barcelona, Spain, 30 March-1 April 2009, pp. 1-5.
   
6. A. Papadogiannis and G. C. Alexandropoulos, "System level performance evaluation of dynamic relays in cellular networks over Nakagami-m fading channels," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Tokyo, Japan, 13-16 September 2009, pp. 727-731.
   
7. L. Jacobs, G. C. Alexandropoulos, M. Moeneclaey, and P. T. Mathiopoulos, "BER performance of OSTBCs on correlated fading channels with imperfect channel estimation," in Proc. Future Network and Mobile Summit Conference, Florence, Italy, 16-18 June 2010, pp. 1-8.
   
8. A. Papadogiannis and G. C. Alexandropoulos, "The value of dynamic clustering of base stations for the wireless networks of the future," in Proc. IEEE World Congress on Computational Intelligence, Barcelona, Spain, 18–23 July 2010, pp. 1-6.
   
9. G. C. Alexandropoulos, A. Papadogiannis, and K. Berberidis, "Relay selection vs. repetitive transmission cooperation: analysis under Nakagami-m fading," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Istanbul, Turkey, 26–29 September 2010, pp. 140-144.
   
10. G. C. Alexandropoulos, A. Conti, and P. T. Mathiopoulos, "Adaptive M-QAM systems with diversity in correlated Nakagami-m fading and shadowing," in Proc. IEEE Global Communications Conference, Florida, USA, 6-10 December 2010, pp. 1-5.
    
11. G. C. Alexandropoulos, S. Papaharalabos, and C. B. Papadias, "On the performance of interference alignment under weak interference conditions," in Proc. IEEE International Conference on Systems, Signals and Image Processing, Vienna, Austria, 11–13 April 2012.
    
12. M. Matthaiou, G. C. Alexandropoulos, H. Q. Ngo, and E. G. Larsson, "Effective rate analysis of MISO Ricean fading channels," in Proc. IEEE Sensor Array and Multichannel Signal Processing Workshop, Hoboken, NJ, USA, 17–20 June 2012.
    
13. T. Q. Duong, D. B. da Costa, G. C. Alexandropoulos, V. N. Q. Bao, and A. Nallanathan, "Cognitive amplify-and-forward relaying with best relay selection in spectrum sharing systems," in Proc. IEEE Global Communications Conference, under review, 2012.
    

1. Research Seminar at National Center for Scientific Research (NCSR)–“Demokritos,” Institute of Informatics and Telecommunications (IIT), Performance analysis of diversity receivers over correlated Weibull fading channels, November 2006.
2. Research Seminar at NCSR–“Demokritos,” IIT, Performance analysis of multiple-input multiple-output systems, June 2007.
3. Research Seminar at NCSR–“Demokritos,” IIT, Performance analysis of diversity receivers over correlated fading channels, April 2008.
4. Invited Talk at University of Patras, School of Engineering, Computer Engineering and Informatics Department, Signal Processing & Communications Laboratory, Performance analysis of multichannel receivers over correlated fading channels, April 2008.
5. Research Seminar at NCSR–“Demokritos,” IIT, Diversity systems in correlated fading channels, July 2008.
6. Invited talk at National Observatory of Athens, Institute for Space Applications and Remote Sensing, Diversity systems in correlated generalized fading channels, December 2008.
7. Research Seminar at the NCSR–“Demokritos,” IIT, Low complexity diversity techniques in correlated fading channels, October 2009.
8. Research Seminar at Athens Information Technology, Analyzing the performance of multiple-antenna systems over non-ideal conditions, April 2011.
9. Invited Talk at Beijing University of Posts and Telecommunications, Wireless Signal Processing and Network Laboratory, Performance analysis of cooperative techniques over generalized fading channels, May 2011.