Asdesach Zena Markos

Research and Teaching Assistant at the Department of High Frequency Engineering, University of Kassel

Universität Kassel, Fachgebiet Hochfrequenztechnik (HFT), Wilhelmshöher Allee 73, 34121, Kassel, Germany. Tel. + 49 561 804 6528,  Fax. -6529, Email: zena@uni-kassel.de.

Current Activity:

• Working towards a PhD dissertation on: Analysis, design and efficiency enhancement of GaN power amplifiers for wireless communication application.

Experiences in Research, Teaching & Industry: 

1. Research and teaching assistant (October 2004- till date) at the Department of High Frequency Engineering, University of Kassel, Germany.

• Analysis, design and realization of power amplifiers for 3G wireless communication applications.

• Efficiency enhancement of GaN power amplifiers using Doherty technique.

• Small- and large-signal characterization of microwave circuits.

• Tutorial classes and practical trainings in microwave engineering courses (transmission line theory and microwave integrated circuits).

• Supervising masters thesis and project works of ECE students.

2. Visiting researcher (Oct. - Nov. 2006) at the Department of Electronic Engineering, University of Rome "Tor Vergata" Rome, Italy.

• Analysis, design and simulation of a 6W GaN Doherty amplifier.

3. Intern (Oct. 2003 - Feb. 2004) with Atmel Germany, Heilbronn, Germany.

• Characterization and modelling of power amplifiers in SiGe technology for WLAN application.

4. Graduate assistant (Aug. 2001 - Mar. 2002) at the Department of  Electrical Engineering  Bahirdar University, Bahirdar, Ethiopia.

•  Tutorial classes in basic electrical engineering courses.

Academic Qualifications:

• M. Sc. in electrical communication engineering (Apr. 2002-Sep. 2004), from the University of Kassel, Germany. Masters thesis:  Design and simulation of power amplifier with minimum memory effect for UMTS Application.

• B. Sc. in electrical engineering (Sep. 1996 - Jul. 2001), from Bahirdar University, Ethiopia. Thesis: Implementation of voice over local area network (LAN).

Publications:

1. A. Z. Markos and G. Kompa, "A High Power Doherty Amplifier Design for UMTS Application," Proc. of the 2008 German Microwave Confernece (GeMiC-2008), Hamburg, Germany, 2008. 

2. E. R. Srinidhi, R. Ma, A. Z. Markos, and G. Kompa, "Optimization of Broadband Drain Modulation in GaN HEMT Devices Measurment," IEEE Proc. of Radio and Wirless Confrence Sym (RWS), pp. 81-84, Orlando, FL, USA, 2008.

3. A. Z. Markos, P. Colantonio, F. Giannini, R. Giofre, M. Imbimbo, and G. Kompa, "A 6W  Uneven Doherty Amplifier in GaN Technology," Proc. of the 2^nd European Microwave Integrated Circuits (EuMIC), pp. 299-302, Munich, Germany, 2007. Best Paper Award. 

4. A. Z. Markos and G. Kompa, "A 2.6W AlGaN/GaN Based Symmetrical Doherty Amplifier Design," Proc. of the 1^st TARGET Days, Frascati, Italy, 2006. 

5. B. Bunz, A. Z. Markos, A. Ahmed, and G. Kompa, "Linearization of High Power Amplifier with Optimized Zone 0 Terminations," Proc. of  the 2006 German Microwave Conference (GeMiC-2006), Karlsruhe, Germany, 2006.

6. A. Z. Markos and G. Kompa, "Design and Simulation of Power Amplifier with Minimum Memory Effect for UMTS Application," Proc. of the 2^nd International Conference in Electrical and Computer Engineering, Bahirdar, Ethiopia 2005.