Ahmed Salah Ibrahim, Ph.D.
Welcome to my homepage.
I received the B.S. (with highest honors) and M.S. degrees in electronics
and electrical communications engineering from Cairo University,
electrical engineering from the
My major is Communications and Signal Processing and my research
interests include cooperative communications and networking, cross-layer
design of wireless networks, relay deployment and selection in wireless
networks, and MIMO-OFDM systems.
I will be very pleased to hear from you. Please, contact me at
Email: firstname.lastname@example.org (asibrahim [AT] ieee [DOT] org)
My resume can be found at Resume .
More information can be found below.
· Ph.D. in Electrical and Computer Engineering May 2009
Thesis: Relay deployment and selection in cooperative wireless networks
· M.S. in Electrical and Computer Engineering Dec. 2007
· M.S. in Electronics and Electrical Communications Engineering Aug. 2004
Thesis: Multilayered space-frequency coding for OFDM systems
· B.S. in Electronics and Electrical Communications Engineering May 2002
Graduation Project MEMS-based IR static earth sensor
Cumulative grade: 90%
· Cross-layer design of wireless networks
· Cooperative communications for wireless networking
· Space-time and space-frequency coding
· MIMO, OFDM
· Cellular systems (LTE, UMB, WiMAX)
· Lifetime maximization in wireless sensor networks
· Cooperative routing
Intel Corporation, Wireless Standards & Technology,
Communication Systems Engineering Intern
Mentors: Dr. Yang-Seok Choi and Dr. Shahrnaz Azizi
o WiMAX (IEEE 802.16m) standards
Designed and evaluated Preamble sequences for MIMO/OFDM-based WiMAX IEEE 802.16m via Matlab; Ran link level and system level simulations of various preamble sequences under different channel models; Designed Location Based Services (LBS) capability for WiMAX; contributed to 1 patent (Preamble design) and 3 contributions (Preamble, LBS, cooperative relaying) in the IEEE 802.16m standards.
Qualcomm Incorporated, Corporate R&D Division,
Communication Systems Engineering Intern
Mentors: Dr. Dhananjay Gore and Dr. Sony Akkarakaran
Developed and tested the modulator/demodulator blocks of all the MIMO/OFDM-based Forward Link Control Segment (FLCS) sub-channels via C++; Ran simulations under different channel models for both fixed and floating point blocks; Wrote a Perl script to generate the performance curves for all the FLCS sub-channels in an easy and efficient way.
Undergraduate Technical Intern
o Micro-Electro Mechanical Systems (MEMS)
Developed Design Rule
Advisor: Prof. K. J. Ray Liu
o Relay-selection in cooperative communications
Answered the fundamental questions of When to cooperate? and Whom to cooperate with?; Proposed a relay-selection scheme for cooperative networks (Matlab); Bandwidth efficiency is boosted by 75% compared to conventional schemes; 3 related papers are published.
o Cooperative routing
Proposed a cooperative-based routing algorithm in wireless ad hoc networks (C/C++, Matlab, Mathematica); Power saving of 65% is achieved; 2 related papers are published.
o Network lifetime maximization
Proposed a network-maintenance scheme to maximize network lifetime of wireless sensor networks by adding a set of relays to it (Matlab); Network lifetime gain of 100% is achieved; Proposed a network-repair scheme to reconnect a disconnected sensor network; 3 related papers are published.
o Mitigating channel estimation error and interference
Showed the impact of various cooperative communication schemes on channel estimation error and interference problems (Matlab); Characterized the tradeoff between channel estimation error and timing synchronization error; 1 related paper is published and 1 is submitted for publication.
Team Leader: Dr. Dalma Novak
o Concealed weapons detection
Developed signal processing techniques for extracting the unique signature of each tested weapon (Matlab, C/C++); Investigated various classification techniques to achieve high probability of detection and low probability of false alarm; 1 related paper is published.
o Research Assistant
Advisor: Prof. Mohamed M. Khairy
Proposed multilayered space-time and space-frequency coding schemes in OFDM systems (Matlab); 2 related papers are published.
o Teaching Assistant
Taught communication and signal processing courses including Communication Systems, Digital Communications, and Signals & Systems.
· Programming Languages: C, C++, Matlab, and Perl.
· Platforms: Linux and Windows.
· Softwares: Mathematica, VHDL, L-Edit, and PSpice.
· Preamble sequence for WiMAX IEEE 802.16m
Proposing a Preamble sequence for Cell-ID detection in the WiMAX IEEE 802.16m system; The proposed Preamble consists of 768 distinct sequences with low-correlation, which allows the WiMAX system to support a large number of base stations, relay stations, and femto cells; It has a scalable structure and has no impact on the performance of the WiMAX IEEE 802.16e legacy devices.
Random processes in communication Wireless communications Error correcting codes
Advanced digital signal processing Advanced numerical optimization Information theory
Estimation & detection theory Numerical analysis Optimal control
Multi-user information theory Space-time signal processing System theory
· Filterbank design and subband coding for images
Designed two-tap perfect reconstruction (PR) Quadrature mirror filter (QMF) bank; used the designed QMF in performing subband coding of images.
· Linear prediction
Predicted the Dow Jones Industrial Average (DJIA) weekly closing price.
· Concealed weapons detection
Actively participated in
writing a technical proposal on signal
processing techniques for concealed weapons detection; accepted by the Maryland Industrial Partnerships (
Included in the 2009 Edition of Who's Who in
· Best Speaker Award of the ECE Seminar Series, University of Maryland, College Park, MD, USA, 2008.
· Nominee for Best Student Paper Award, IEEE Conf. on Acoustics, Speech and Signal Processing (ICASSP), 2007.
IEEE Travel Grant
for participating in IEEE ICASSP,
Goldhaber Travel Grant,
Schlumberger's Award for best senior students,
· Distinction with Honor at B.Sc. degree, 2nd on a class of 352 students, Cairo University, Cairo, Egypt, 2002.
IMEC Summer Scholarship,
Certificate of Merit, First Class Honors,
· Paper Reviewer
IEEE Transactions on Communications, IEEE Transactions on Signal Processing, IEEE Transactions on Wireless Communications, IEEE Journal on Selected Areas in Communications, IEEE Global Telecommunications Conference (Globecom), IEEE International Conference on Communications (ICC), IEEE Wireless Communication and Networking Conference (WCNC), IEEE Information Theory Workshop (ITW), and IEEE Vehicular Technology Conference (VTC).
Technical Program Committee
International Wireless Communications and
Institute of Electrical and Electronics Engineers (IEEE).
· Engineering Graduate Student Council (EGSC) Member (Dec. 2004 - May 2006)
Led the council in organizing an orientation for the new engineering graduate students; Participated in preparing a survey about the major problems facing the engineering graduate students.
· Journal Papers
1. A.S. Ibrahim and K.J.R. Liu, Mitigating channel estimation error effects with timing synchronization tradeoff in cooperative communications, to appear in IEEE Trans. on Signal Processing, 2009.
2. A.S. Ibrahim, K G. Seddik, and K.J.R. Liu, Connectivity-aware network maintenance and repair via relays deployment, IEEE Trans. on Wireless Communications, vol. 8, pp. 356-366, Jan. 2009.
3. A.S. Ibrahim, Z. Han, and K.J.R. Liu, Distributed energy-efficient cooperative routing in wireless networks, IEEE Trans. on Wireless Communication, vol. 7, pp. 3930-3941, Oct. 2008.
4. A.S. Ibrahim, A.K. Sadek,
5. K.G. Seddik, A.K. Sadek, A.S. Ibrahim, and K.J.R. Liu, Design criteria and performance analysis for distributed space-time coding, IEEE Trans. on Vehicular Technology, vol. 57, pp. 2280-2292, Jul. 2008.
6. K.G. Seddik, A.S. Ibrahim, and K.J.R. Liu, Trans-modulation in wireless relay networks, IEEE Communications Letter, vol. 12, Is. 3, pp. 170-172, .Mar. 2008.
7. Hung-Quoc Lai, A.S. Ibrahim, and K.J.R. Liu, Wireless network cocast: location-aware cooperative communications with linear network coding, to appear IEEE Trans. on Wireless Communications, 2009.
8. M. Baidas, A.S. Ibrahim, K G. Seddik, and K.J.R. Liu, Correlation-Based Cooperation for Distributed Detection in Wireless Sensor Networks: Analysis and Modeling, in revision, IEEE Trans. On Wireless Communication.
· Conference Papers
1. A.S. Ibrahim and K.J.R. Liu, Mitigating channel estimation error via cooperative communications, Proc. IEEE International Conference on Communications (ICC'09), Jun. 2009.
2. M. Baidas, A.S. Ibrahim, K G. Seddik, and K.J.R. Liu, On the impact of correlation on distributed detection in wireless sensor networks with relays deployment, Proc. IEEE International Conference on Communications (ICC'09), Jun. 2009.
3. Hung-Quoc Lai, A.S. Ibrahim, and K.J.R. Liu, Location-aware cooperative communications utilizing linear network coding, Proc IEEE Global Telecommunications Conference (Globecom'08), pp. 1-5, Nov. 2008.
4. A.S. Ibrahim, K G. Seddik, and K.J.R. Liu, Connectivity-aware network maintenance via relays deployment, Proc. IEEE Wireless Comm. and Networking Conference 2008 (WCNC'08), pp. 2573-2578, Apr. 2008.
5. A.S. Ibrahim, K G. Seddik, and K.J.R. Liu, Improving connectivity via relays deployment in wireless sensor networks, Proc. IEEE Global Telecommunications Conference (Globecom'07), pp. 1159-1163, Nov. 2007.
6. A.S. Ibrahim, Z. Han, and K.J.R. Liu, Distributed energy-efficient cooperative routing in wireless networks, Proc. IEEE Global Telecommunications Conference (Globecom'07), pp. 44134418, Nov. 2007.
7. K.G. Seddik, A.K. Sadek, A.S. Ibrahim, and K.J.R. Liu, Synchronization-aware distributed space-time codes in wireless relay networks," Proc. IEEE Global Telecommunications Conference (Globecom'07), pp. 3452-3456, Nov. 2007.
8. A.S. Ibrahim, K.J.R. Liu, D. Novak, and R.B. Waterhouse, A subspace signal processing technique for concealed weapons detection, Proc. International Conference on Acoustics, Speech, and Signal Processing (ICASSP07), pp. II-401 - II-404, Apr. 2007. (Nominee of the Best Student Paper Award)
9. A.S. Ibrahim, A.K. Sadek, W. Su, and K.J.R. Liu, Relay selection in multi-node cooperative communications: when to cooperate and whom to cooperate with?, Proc. IEEE Global Telecommunications Conference (Globecom'06), pp. 1-5, Nov. 2006.
10. A.S. Ibrahim,
11. A.S. Ibrahim, M.M.
Khairy, and A.F. Hussein, Multilayered
space-frequency block coded OFDM systems, Proc. The Global Signal
Processing EXPO and Conference,
12. A.S. Ibrahim,
M..M. Khairy, and A.F. Hussein Multilayered
space-time block codes for OFDM systems, Proc. The International
Conference on Electrical, Electronic and Computer Engineering,
13. A.S. Ibrahim, A. Adel, A. Ezeldin, A. Ali, A. Hussein, and S.E.-D. Habib, Design and implementation of an area-efficient MEMS-based IR static earth sensor, Proc. The 15th IEEE International Conference on Microelectronics (ICM), pp. 143 - 146, Dec. 2003.
14. S. Pamidighantam, W. Laureyn, A.S. Ibrahim, A. Verbist, H.A.C. Tilmans, A novel process for fabricating slender and compliant suspended poly-Si micro-mechanical structures with sub-micron gap spacing, Proc. The 15th IEEE Conference on Micro Electro Mechanical Systems, pp. 661-664, 2002.