The LML detectors investigated in this project provide a new means of multiuser detection for CDMA network to increase usable bandwidth and network throughput. The proposed investigation will impact basic research in signal processing for multiuser communications, and is expected to benefit directly applications to fourthgeneration wireless mobile communications systems. This project will contribute new knowledge and method to applications to broad areas of wireless communication networks, highspeed data transmission, wireless internet service, digital television, magnetic recording, global positioning systems, and image processing, and to theories of the fields of multiuser detection, hypothesis testing, wireless communications, neural networks, and image processing.
The area of communications in the PI’s Department of Electrical Engineering at the City Collage of New York is currently relatively weak. Only the PI is in the area of physical layer communications. Several communication related courses such as Spread Spectrum and Information Theory and Coding have not been offered for long since a senior faculty member was retired. Several other modern communication courses such as Digital Communications at both undergraduate and graduate levels, and Statistical Signal Estimation and Detection at graduate level have not been included in the curriculum (the faculty meeting of this department just approved PI’s proposal to open Digital Communications I, and II at graduate level in next year). On the other hand, several surveys showed significant student demand on opening communication courses. This department has decided to develop a strong communication program. The hiring process for a new faculty member in telecommunications has been activated. Currently this PI works on a research project in the Collaborative Technology Alliances (CTA) program supported by ARL. This PI directs three Ph.D. students in addition to about five MS projects and reports and five undergraduate students in independent study yearly. The City College of New York is a minority college. Each year several minority students (most are MS and undergraduate students) participated in the research with the PI through assigning them projects and independent study. The support of this proposed project will help set up a strong program in communications in this department and provide new research opportunities for both graduate and undergraduate students, and in particular the minority students. The increased minority students’ research activities in modern communications will strengthen the traditional diversity environment of this collage.
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Y. Sun, "Hopfield neural network based algorithms for image restoration and reconstruction  Part II: performance analysis," IEEE Trans. on Signal Processing, vol. 48, no. 7, pp. 21192131, July 2000.

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Biographical Sketch
Yi Sun
Department of Electrical Engineering
The City College of the City University of New York
Convent Avenue at 138^{th} Street
New York, NY 10031
Phone: (212)6506621; Fax: (212) 6508249
Email: sun@ccny.cuny.edu
Education
Ph.D., EE, University of Minnesota, Minneapolis, MN, 1997
MSEE, Shanghai Jiao Tong University, Shanghai, P. R. China, 1985
BSEE, Shanghai Jiao Tong University, Shanghai, P. R. China, 1982
Professional Experience
Assistant Professor, City College of City University of New York, New York, NY, Sept. 1998 
Postdoctoral Research Associate, University of Connecticut, Storrs, CT, Oct. 1997Aug. 1998
Postdoctoral Research Fellow, University of Utah, Salt Lake City, Utah, MarchSept. 1997
Research intern, Northern Telecom, Eagan, MN, summer 1996  Jan. 1997
Research intern, ADC Telecommunications, Minnetonka, MN, summer 1995
Research and Teaching Assistants, University of Minnesota, Minneapolis, MN, 1993  1996
Visiting Scientist, Concordia University, Montreal, Canada, summer 1993
Lecturer, Shanghai Jiao Tong University, Shanghai, P. R. China, 19851993
Publications Related to Proposed Project
[1] Y. Sun, “Local maximum likelihood multiuser detection,” in Proc. 34th Annual Conference on Information Science and Systems, CISS'2001, pp. 712, The Johns Hopkins University, Baltimore, Maryland, March 2123, 2001.
[2] Y. Sun, “A family of linear complexity likelihood ascent search multiuser detectors for CDMA communications,” in Proc. 34th Asilomar Conference on Signals, Systems, and Computers, vol. 2, pp. 1163 1167, Pacific Grove, CA, Oct. 29  Nov. 1, 2000.
[3] Y. Sun, "Hopfield neural network based algorithms for image restoration and reconstruction  Part I: algorithms and simulations," IEEE Trans. on Signal Processing, vol. 48, no. 7, pp. 21052118, July 2000.
[4] Y. Sun, "Hopfield neural network based algorithms for image restoration and reconstruction  Part II: performance analysis," IEEE Trans. on Signal Processing, vol. 48, no. 7, pp. 21192131, July 2000.
[5] Y. Sun, "A generalized updating rule for modified Hopfield neural network for quadratic optimization," Neurocomputing, pp.133143, 19 (1998).
Other Significant Publications
[1] Y. Sun, "Bandwidthefficient wireless OFDM," IEEE J. on Select. Area in Commun., vol. 19, no. 11, pp. 22672278, Nov. 2001.
[2] Y. Sun and D. Parker, "Small vessel enhancement for MRA images using local maximum mean processing," IEEE Trans. on Image Processing, vol. 10, no. 11, pp. 16871699, Nov. 2001.
[3] Y. Sun and D. Parker, "Performance analysis of maximum intensity projection algorithm for display of MRA images," IEEE Trans. on Medical Imaging, vol. 18, no. 12, pp. 11541169, Dec. 1999.
[4] Y. Sun, "Stochastic iterative algorithms for signal set design for Gaussian channels and optimality of the L2 signal set," IEEE Trans. on Information Theory, vol. 43, pp. 15741587, Sept. 1997.
[5] Y. Sun, J.G. Li and S.Y. Yu, “Improvement on performance of modified Hopfield neural network for image restoration,” IEEE Trans. on Image Processing, Vol. 4, No. 5, pp. 688692, May 1995.
List of Collaborators
Prof. Myung Lee City College of New York
Prof. Terak Saadawi City College of New York
Prof. Dennis Parker University of Utah
(applicant’s postdoctoral advisor, 20 graduates, 3 postdoctors)
Prof. Lang Tong Cornell University
(applicant’s postdoctoral advisor, 10 graduates, 4 postdoctors)
Prof. John Kieffer University of Minnesota
(applicant’s Ph.D. advisor)
Dr. Laurie Nelson IDA Center for Communications Research
(applicant’s Ph.D. coadvisor)
Page A
NSF CISE: Communications, (Y. Sun)
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