Ph.D. Candidate, ECE Department, University of Massachusetts Amherst
Tel.: 413-253-9267(H); 413-244-6505(C); 413-545-0963(O)
Email: quzhang@ecs.umass.edu
Resume, Education, Research, Industry Experience, Teaching Experience,
Publications, Activities, Skills, Awards,
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SUMMARY:
PhD candidate with strong background on communications, rich experience of research and teaching, and bilingual ability seeking a research and development position focusing on practical problem solving and/or product development in industries specific in the area of communications, signal processing or information technology.
RESEARCH INTERESTS:
M.S., April 2001, Communications and Information System
B.S., July 1998, Computer Communications
July 2002 -- Present, Research Assistant, Department of Electrical and Computer Engineering
-- Proposal of slightly frequency-shifted reference ultra-wideband radio (FSR-UWB):
A major difficulty of implementation of the UWB system is its receiver design. Due to the high multipath resolution of the UWB system, the conventional Rake receiver implementaion is impractical because of the huge number of taps and the problem of channel estimation. The transmitted-reference (TR) UWB is one solution to the receiver design problem, particularly for low data rate applications. However, to accuratelyimplement a wideband delay element in a highly integrated low power circuit is not an easy task. We proposed a new transmitted reference UWB scheme without delay element. It can be shown that the proposed scheme not only outperforms the conventional TR-UWB, and but also provides a very simple receiver structure. A multi-differential FSR-UWB and a multiple access scheme of the FSR-UWB were also proposed. Moreover, we provided a simple synchronization scheme for the proposed scheme.
-- Analysis on power spectral density (PSD) and peak-to-average power ratio (PAPR) of OFDM systems:
A major drawback of the multi-carrier system like OFDM is the high peak-to-average power ratio. Most of previous works on PAPR analysis of the OFDM system adopted a continuous time OFDM signal model other than the practically used discrete time IDFT-based OFDM signal model. We derivated accurate closed form expressions of the PSDs of the transmitted signal of both continuous time and the IDFT-based OFDM systems, taking into account of effects of cyclic prefix, windowing, digital-to-analog converter, null-subcarriers, analog filtering and power allocation. It was shown that two similar systems leads to different PSDs of thetransmitted signal. The PAPR distribution was derivated by using extreme-value theory. We showed that the PAPR distribution is characterized by the length of observation interval and the root mean square bandwidth of the signal, whose computation requires the PSD of the transmitted signal.
-- Design of RAKE receivers for UWB:
RAKE receivers for the UWB system employing binary block-coded pulse-position-modulation (PPM) were considered in dense multipath channels. Optimum and suboptimum designs were investigated with various finger selection and combining criteria such as the maximum energy capture (MEC), the maximum signal-to-noise ratio (MSNR), and the minimum bit-error-rate (mBER) criteria. The combining weights for the MEC, the MSNR, and the mBER criteria were derived and shown to be distinct in general. Conditions for MSNR and/or MEC receivers to perform comparably to the mBER receiver are also derived.
July 1999 每 August 2000, Research Assistant, College of Communications and Information Engineering
-- Software implementation of ITU-T V.42:
Realized the error control protocol ITU-T V.42 as well as physical drivers, flow control, error control and automatic switch in C and assembly language for digital MUX.
December 1999 每 December 2000, Co-op, High-frequency Communication Lab
-- Automatic Link Establishment (ALE) module played an important role in the Adaptive High-frequency Radio System, which was a National Ninth Five-year Development Program of China. I participated in the designing of the 8FSK modem used in the physical layer of ALE and implemented software of the 8FSK modem using C and assembly language in on ADSP-21062. The Adaptive High-frequency Radio System successfully passed the state inspection in December 2000.
February 1998 每 June 1998, Intern, Sector of Technology Development
-- Alcatel S1240 digital exchange has a powerful trunk test capability. However, most clients are not fimilar with the complicated trunk test commands and their feedbacks. I designed and implemented the improved trunk test module (TTM) with a user-friendly interface using Microsoft Visual C++ on Windows 95 platforms. The real-time TTM can be then processed in a computer connected to Alcatel S1240 digital exchange through a RS-232 serial port.
September 2001 每 July 2002, Teaching Assistant, Department of Electrical and Computer Engineering
-- Courses: ECE211 Circuit Analysis, ECE563 Communication System, ECE564 Digital Signal Processing and ECE603 Probability and Random Process
-- Responsibilites: Led lab sessions, host office hours, graded homework and exams, and helped students with course projects.
-- Outstanding TA of ECE department, UMass Amherst in 2001-2002 academic year.
* Qu Zhang and Dennis L. Goeckel, ※Multi-differential slightly frequency-shifted reference UWB radio§, CISS 2006, March, 2006
* Dennis L. Goeckel and Qu Zhang, ※Slightly frequency-shifted reference UWB radio§, accepted byIEEE Transactions on Communications, August 2006
* Qu Zhang and Dennis L. Goeckel, ※Using extreme bandwidths for simplicity: UWB multiple-access with AM receiver complexity§, submitted to Allerton Conference 2006, July 2006
* Dennis L. Goeckel and Qu Zhang, ※Slightly frequency-shifted reference UWB radio: TR-UWB without the delay element§, MILCOM 2005, October, 2005
* Qu Zhang and Dennis L. Goeckel, ※FSR-UWB (TR-UWB without the delay element): Effect of impulse dithering and experimental results§, ICUWB 2006, September 2006
* Qu Zhang and Joon Ho Cho, ※PAPR performance of IDFT-based uncoded OFDM signals with null subcarriers and transmit filtering§, ICC 2006, June 2006
* Qu Zhang and Joon Ho Cho, ※On RAKE recievers for ultra-wideband binary block-coded PPM in dense multipath channels§, revision submitted to IEEE Transactions on Vehicular Technology, April 2006
* Joon Ho Cho and Qu Zhang, ※Design of RAKE receiver for ultra-wideband binary block-coded PPM in dense multipath channels§, MILCOM 2003, October, 2003
DISSERTATION (Draft):
Top* Qu Zhang, ※Slightly frequency-shifted reference ultra-wideband radio§, August, 2006
* IEEE Student Member, 2002 - 2006
* Reviewer of the following publications:
-- IEEE Transactions on Vehicular Technology
-- IEEE International Conference on Communications (ICC)
-- IEEE Global Telecommunications Conference (GLOBECOM)
-- IEEE International Conference on Ultra-wideband (ICUWB)
-- IEEE Vehicular Technology Conference (VTC)
* Programming: C, Matlab, Foxpro, BASIC, PASCAL, Assembly language, C++
* DSP: ADSP 2106x, TMS320C54
* Platforms: Windows, DOS, UNIX, pSOS+
* Word Processing: Latex, Microsoft Word, Microsoft PowerPoint
* Standards: 802.11(a/b/g), 802.15 (3a/4a), ITU-T v.42, ITU-T v.42bis, IS-95, GSM, CDMA2000, ITU-T v.21
* Languages: English, Chinese
HOBBIES:
Reading, hiking, fishing, traveling, badminton, tennis and basketball
CONTACT ME:
Tel. (413)-253-9267 (H); (413)-244-6506 (C); (413)-545-0963 (O)
Email: quzhang@ecs.umass.edu
Formats: pdf, plain text, doc
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This site is maintained by Qu Zhang, University of Massachusetts
Amherst
Last Updated
21-Aug-2006