M.Sc. Electrical Engineering Circuits and Systems
Department of Electrical and Electronic Engineering
Malek Ashtar University of Technology, 15875-1774, Iran
School of Electrical and Computer Engineering
University of Tehran, 14395-1465, Iran
Tel (SILab at UT): +98 21 880 13196
Personal Homepage: http://ece.ut.ac.ir/silab/asaghafi/
Ahmad Saghafi was born in December 1979 in Tehran, Iran. He received the B.Sc. degree in Electrical Engineering in July 2003 from Semnan University, Semnan, Iran. From September 2003 to October 2006, he was an M.Sc. student of Electrical Engineering at Malek Ashtar University of Technology, Tehran, Iran. In December 2004, he joined the "Silicon Intelligence and VLSI Signal Processing Laboratory" at the University of Tehran as a graduate research assistant and started working on his master thesis entitled "Design of Baseband Section of a Coherent UWB Receiver" under the direct supervision of Prof. Sied Mehdi Fakhraie. His research interests include design and implementation of VLSI signal processing and communication systems, signal processing for communications, and ultra-wideband system design. He has served as TPC member and reviewer in several international conferences and has been a student member of IEEE since January 2005.
Design and Implementation of VLSI Signal Processing and Communication Systems
Development of Algorithms for Wireless Communications
Application of UWB Communication Systems in WPANs, WSNs, and SoC Interconnections Design
VLSI/FPGA Implementation of DSP Systems
Computer Aided Design of Digital Integrated Circuits and Systems
HW/SW Codesign and Embedded Systems Design
RF Integrated Circuit Design for Emerging Wireless Communication Systems
Dec. 2004 Oct. 2006: Research Assistant, Silicon Intelligence & VLSI Signal Processing Lab., School of ECE, University of Tehran, Iran
May 2006 July 2007: Research Assistant, Research Institute of Advanced Technologies in Automotive Industry, Tehran, Iran
Oct. 2005 Mar. 2006: Instructor, Pishro Noavaran Kavosh Co., Tehran, Iran
Dec. 2001 July 2003: Research Assistant, Electronics Design Lab., Department of ECE, Semnan University, Semnan, Iran
Aug. 1995 Oct. 1996: Software Developer, Dana Pazhoohesh Ertebat Co., Tehran, Iran
Instructor, Department of Engineering, Islamic Azad University, Shahre Rey, Iran
Fall 2007 to present: Junior-Level Course, Digital Logic Circuits
Fall 2008: Junior-Level Course, Electronic Circuits
Fall 2007 to present: Junior-Level Course, Technical English
Fall and Spring 2007: Junior-Level Course, Digital Logic Circuits Laboratory
Instructor, Department of Electrical Engineering, Shahid Sattari Aviation University, Tehran, Iran
Fall 2007 to Fall 2008: Junior-Level Course, Electrical Measurement Laboratory
Instructor, Kanoon Danesh Anformatik, Tehran, Iran
July 1999 to Sep. 2004: Some ICDL Courses, including Using Windows and Word Processing and Using Internet (summer only)
Teaching Assistant, Department of Electrical and Computer Engineering, Semnan University, Semnan, Iran
Spring 2002: Junior-Level Course, Electric Circuit Theory
Manuscripts in Progress
1. A. Saghafi and S. M. Fakhraie, Two-Stage Search Space Reduction Algorithm for UWB Signal Acquisition, submitted to IEEE Transaction on Wireless Communications in May 2008.
1. M. Hamzeh, H. R. Mahdiani, A. Saghafi, S. M. Fakhraie, and C. Lucas, Computationally Efficient Active Rule Detection Method: Algorithm and Architecture, accepted for publication in Fuzzy Sets and Systems (FSS), 2008.
2. A. Saghafi and S. M. Fakhraie, Optimized Baseband Design of an Ultra-Wideband Impulse Radio Receiver, in Proc. IEEE Intl. Conf. Ultra-Wideband (ICUWB'07), Singapore, Sep. 2007, pp. 805808.
3. A. Saghafi and S. M. Fakhraie, An Exact Analysis of the Linear Serial Acquisition for Ultra-Wideband Communication Systems, in Proc. IEEE Intl. Conf. Ultra-Wideband (ICUWB'07), Singapore, Sep. 2007, pp. 880883.
4. A. Saghafi and S. M. Fakhraie, A New Search Space Reduction Technique for Acquisition of UWB Signals in Multipath Channels, in Proc. IEEE Vehicular Technology Conf. (VTC'07), Dublin, Ireland, Apr. 2007, pp. 15591563.
5. A. Saghafi and A. Nabavi, An Ultra-Wideband Low-Noise Amplifier for 35-GHz Wireless Systems, in Proc. Intl. Conf. Microelectronics (ICM'06), Dhahran, Saudi Arabia, Dec. 2006, pp. 20-23.
6. A. Saghafi and S. M. Fakhraie, Rapid Acquisition of Ultra-Wideband Signals in Multi- path Environments, in Proc. IEEE Asia Pacific Conf. Circuits and Syst. (APCCAS'06), Singapore, Dec. 2006, pp. 18181821.
1. Design of Baseband Section of a Coherent UWB Receiver, M.Sc. Thesis, Malek Ashtar University of Technology, Tehran, Iran, Oct. 2006. [Download]
2. Baseband Design of an Ultra-Wideband Radio Receiver (Simulations and Analysis), Silicon Intelligence and VLSI Signal Processing Lab., Jul. 2006. [Download]
3. An Overview of Ultra-Wideband Systems, and Using Simulink for System Modeling, Silicon Intelligence and VLSI Signal Processing Lab., Feb. 2006. [Download]
4. A Survey on Ultra-Wideband Standard and Research Activities, M.Sc. Seminar, Malek Ashtar University of Technology, Tehran, Iran, Jul. 2005. [Download]
5. An Overview of Ultra-Wideband Systems and Challenges Ahead, Silicon Intelligence and VLSI Signal Processing Lab., Jul. 2005. [Download]
Ultra-wideband (UWB) radio is a promising technology for low-cost, high-rate communications at short ranges. However, high bandwidth and low power of the UWB signals impose some difficult challenges in signal processing and implementation of the receiver. In this thesis, we have designed the most important parts of a coherent UWB receiver with the purpose of performance improvement and complexity reduction. Specifically, a new method for acquisition of UWB signals in multipath noisy channels is introduced which significantly reduces the mean acquisition time while adds no additional complexity. The performance of the proposed method is analytically evaluated and the results are validated through computer simulations. One of the most important bottlenecks in the design of low-power UWB receivers is channel estimation. An improved method for channel estimation with low computational complexity is proposed. Although, the estimation precision of the method is lower than the conventional methods, it can be implemented with much less complex hardware. In order to efficiently implement the receiver, we have analytically investigated the effects of quantization noise introduced by analog to digital converter and other internal fixed-point operations. Using the analysis, the optimum values for bit width of the internal signals and operations are exploited. For the simulations we performed in this thesis, a complete fully parameterized model of the system including transmitter, multipath noisy channel, and receiver is designed using the C S-Function capability of the MATLAB/Simulink software. A bit-true model of the important parts of the receiver is also designed to evaluate the effects of finite word-length and to validate the results of our quantization noise analysis.
Last Update: November 1, 2008.