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A profile photo of Dariush Divsalar

Dariush Divsalar

Senior Research Scientist

Dariush.Divsalar@jpl.nasa.gov

About

Bio

Dariush Divsalar received the Ph.D. degree in electrical engineering from UCLA, in 1978. Since then, he has been with the Jet Propulsion Laboratory (JPL), California Institute of Technology (Caltech), where he is a Principal Scientist. At JPL, he has been involved with developing state-of-the-art technology for advanced deep space communications systems and future NASA space exploration. Since 1986, he has taught graduate courses in communications, and coding at UCLA and Caltech. He has published more than 200 papers, coauthored a book entitled An Introduction to Trellis Coded Modulation with Applications, contributed to two other books, and holds 19 U.S. patents in the above areas. He was corecipient of the 1986 paper award of the IEEE Transactions on Vehicular Technology. He was also co recipient of the joint paper award of the IEEE Information Theory and IEEE Communication Theory societies in 2008. The IEEE Communication Society has selected one of his papers for inclusion in a book entitled The Best of the Best: Fifty Years of Communications and Networking Research, containing the best 56 key research papers ever published in the Society’s 50-year history. He has received over 40 NASA Tech Brief awards and a NASA Exceptional Engineering Achievement Medal in 1996. He served as an Area Editor for the IEEE Transactions on Communications from 1989 to 1996. He became a Fellow of IEEE in 1997 for contributions to the analysis and design of coding and modulation techniques for satellite, mobile, and deep-space communication systems.

Education

  • 1977-78 University of California, Los Angeles (UCLA), Ph. D. in Electrical Engineering, Dec. 1978.
    • Major: Communication Systems, Department of Electrical Engineering.
    • Minor: Computer System Modeling and Analysis, Department of Computer Science.
    • Minor: Applied Mathematics, Department of Mathematics.
  • 1975-77 University of California, Los Angeles (UCLA), Engineer Degree, June 1977.
  • 1973-75 University of California, Los Angeles (UCLA) M.S. in Electrical Engineering, March 1975.

Research Interests

Research in digital communication systems, wireless communication systems, bandwidth efficient combined coding modulation techniques, digital signal processing, satellite communications, mobile communications. Channel coding for deep space communications. Spread Spectrum Systems, CDMA, Fast Frequency Hopping, Time Hopping for commercial multiple access systems, Acquisition and tracking for spread spectrum communications, Mutual User Interference Cancellation for CDMA, Turbo codes, LDPC codes and Iterative Decoding for power- and Bandwidth- limited Channels.

Experience

Professional Experience

  • 1978-present. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA.
    • 2000 Principal Scientist
    • 1999 Senior Research Scientist
    • 1997 Principal of Engineering Staff.
    • 1989 Senior Member of Technical Staff.
    • 1982 Member of Technical Staff.
    • 1978 Senior Engineer.
  • 1986-1997 Lecturer at UCLA, Electrical Engineering Department Teaching graduate courses in Information Theory, Digital Communications, Coding (TCM, and turbo codes), and Spread Spectrum Communications.
  • 1984-1991 Adjunct Professor at Northrop University Teaching courses in analog and digital communication systems, information theory and error control coding, statistical communication theory, digital communications, probability, stochastic processes, feedback control systems, spread spectrum communications, linear networks, computer networks, digital signal processing.
  • 1982-1996 Distinguished Lecturer at West Coast University Teaching courses in Detection of Signals in Noise, Digital Communication Systems, Coding, Probability, Stochastic Processes, Logic Network Design, Digital Signal Processing, Spread Spectrum.

Achievements

Awards & Recognitions

  • Professional Society and External Organization Awards | Institute of Electrical and Electronics Engineers (IEEE) (?)
  • JPL Fellowship | For pioneering work in the field of telecommunications and signal processing through the development of elegant, simplistic solutions in coding and modulation that have increased data return from spacecraft and advanced 3G/4G cellular standards for terrestrial communications. (2015)
  • Paper Award | Joint paper award (2008)
  • Senior Research Scientist | Digital Communication, Information and Coding Theory (1999)
  • JPL Principal Designation | 332B - Information Processing (1997)
  • NASA Award | NASA Exceptional Engineering Achievement Medal (1996)
  • Professional Society Fellowship | IEEE | Fellow of IEEE (1995)
  • Paper Award | Best paper of the year award (1990)

Publications

  1. D. Divsalar and M. K. Simon, "Spectral Characteristics of Convolutionally Coded Digital Signals," IEEE Trans. on Communications, February 1980.
  2. D. Divsalar and M. K. Simon, "The Power Spectral Density of Digital Modulations Transmitted Over Nonlinear Channels," IEEE Trans. on Communications, Vol. COM-30, January 1982.
  3. D. Divsalar and J. H. Yuen, "Carrier Arraying with Coupled Phase-Locked Loops for Tracking Improvement," IEEE Trans. on Communications, Special Issue on Phase- Locked Loops, October 1982.
  4. D. Divsalar, R. M. Gagliardi and J. H. Yuen, "PPM Performance for Reed- Solomon Decoding Over an Optical-RF Relay Link," IEEE Transactions on Communications, March 1984.
  5. D. Divsalar, M. K. Simon and J. H. Yuen, "Trellis Coding with asymmetric Modulations," IEEE Transactions on Communications, Vol. COM-35, No. 2, February 1987.
  6. D. Divsalar and M. K. Simon, "Trellis Coded Modulation for 4800-9600 bps Transmission Over a Fading Mobile Satellite Channel," Special Issue on Fading Channels of the IEEE Journal on Selected Areas in Communications, Vol. SAC-5, No. 2, February 1987, pp. 162-175.
  7. D. Divsalar and M. K. Simon, "Multiple Trellis Coded Modulation (MTCM)," IEEE Transactions on Communications, April 1988.
  8. M. K. Simon and D. Divsalar, "The Performance of Trellis Coded Multilevel DPSK on a Fading Mobile Satellite Channel," IEEE Trans. on Vehicular. Tech., May 1988.
  9. M. K. Simon and D. Divsalar, "Doppler Corrected Differential Detection of MDPSK," IEEE Trans. on Comm., February 1988.
  10. D. Divsalar and M. K. Simon, "The Design of Trellis Codes for Fading Channels: Performance Criteria," IEEE Transactions on Communications, Vol. COM-36, No. 9, September 1988.
  11. D. Divsalar and M. K. Simon, "The Design of Trellis Codes for Fading Channels: Set Partitioning for Optimum Code Design for MPSK Signals," IEEE Transactions on Communications, Vol. COM-36, No. 9, September, 1988.
  12. D. Divsalar and M. K. Simon, "The Use of Interleaving for Reducing Radio Loss in Trellis Coded Modulation Systems," IEEE Transactions on Communications, Vol. 38, No. 3, August 1990.
  13. D. Divsalar and M. K. Simon, "Multiple Symbol Differential Detection of MPSK," IEEE Transactions on Communications March 1990.
  14. D. Divsalar, M. K. Simon and M. Shahshahani, "The Performance of Trellis Coded MDPSK with Multiple Detection," IEEE Transactions on Communications, September 1990.
  15. J. H. Yuen, M. K. Simon, W. Miller, F. Pollara, C. R. Ryan, D. Divsalar and J. Marakis, "Modulation and Coding for Satellite and Space Communications," proceedings of the IEEE, Vol. 78, No. 7, July 1990.
  16. M. K. Simon and D. Divsalar, "On the Implementation and Performance of Single and Double Differential Detection Schemes," IEEE Transactions on Communications, February 1992.
  17. M. K. Simon and D. Divsalar, "Maximum-Likelihood Sequence Detection of Non coherent Continuous Phase Modulation," IEEE Transactions on Communications, January 1993.
  18. M. K. Simon and D. Divsalar, "Multiple Symbol Partially Coherent Detection of MPSK," IEEE Transactions on Communications, February 1994.
  19. D. Divsalar and M. K. Simon, "Maximum-Likelihood Differential Detection of Uncoded and Trellis Coded Amplitude-Phase Modulation Over AWGN and Fading Channels, Metrics and Performance," IEEE Transactions on Communications , January 1994.
  20. H. Lee, D. Divsalar and C. Weber, "Multiple Symbol Trellis Coding for Full Response CPFSK" IEEE Transactions on Communications, May 1996.
  21. S. Benedetto, D. Divsalar, G. Montorsi and F. Pollara, " Bandwidth Efficient Parallel Concatenated Coding Schemes," IEE Electronics Letters, November 1995, Vol. 31, No. 24.
  22. S.Benedetto, D. Divsalar, G. Montorsi and F. Pollara, "A new algorithm for continuous decoding of turbo codes," IEE Electronics Letters, Feb. 1996.
  23. D. Divsalar, and R. J. McEliece, " The Effective Free Distance of Turbo Codes," IEE Electronics Letters, February 96.
  24. S. Benedetto, D. Divsalar, G. Montorsi, and F. Pollara, "Serial Concatenation of Interleaved Codes: Performance Analysis, Design, and Iterative Decoding," IEEE Transactions on Information Theory , May 1998
  25. S. Benedetto, D. Divsalar, G. Montorsi, and F. Pollara, "Soft Input Soft Output APP Module for Iterative Decoding of Concatenated Codes," IEEE Communications Letters January 1997.
  26. M.K. Simon, and D. Divsalar, "On the Optimality of Classical Coherent Receivers of Differentially Encoded M-PSK,” IEEE Communications Letters, May 1997.
  27. S. Benedetto, D. Divsalar, G. Montorsi, F. Pollara, “ Analysis, Design, and Iterative Decoding of Double Serially Concatenated Codes with Interleavers". IEEE Journal on Selected Areas in Communications, Special Issue on Concatenated Coding Techniques and Iterative Decoding: Sailing Toward Channel Capacity, February 98.
  28. S. Benedetto, D. Divsalar, G. Montorsi, F. Pollara, "Soft-Input Soft-Output Modules for the Construction and Distributed Iterative Decoding of Code Networks," European Transactions on Telecommunications, March-April 98 (invited paper).
  29. M.K. Simon, D. Divsalar, "Some New Twists to Problems Involving the Gaussian Probability Integral,” IEEE Transaction on Communications, February 1998.
  30. D. Divsalar, M.K. Simon, and D. Raphaeli, "Improved Parallel Interference Cancellation for CDMA,” IEEE Transaction on Communications, February 1998.
  31. D. Raphaeli, and D. Divsalar, " Multiple-Symbol Noncoherent Decoding of Uncoded and Convolutionally Coded Continuous Phase Modulation,” Journal of Communications and Networks, December 1999.
  32. D. Divsalar, S. Dolinar, and F. Pollara,“Iterative Turbo Decoder Analysis Based on Density Evolution,” IEEE Journal on Selected Areas in Communications, Vol. 19, No. 5, pp 891-907, May 2001.
  33. R. Garello, G. Montorsi, S. Benedetto, D. Divsalar, F. Pollara, "Labelings and Encoders with the Uniform Bit Error Property with Applications to Serially Concatenated Trellis Codes," IEEE Transaction on Information Theory, Jan. 2002.
  34. Sason, I.; Shamai, S.; Divsalar, D., “Tight exponential upper bounds on the ML decoding error probability of block codes over fully interleaved fading channels ,’’ IEEE Transactions on Communications , Volume: 51 , Issue: 8 , Aug. 2003, Pages:1296 - 1305.
  35. Benedetto, S.; Montorsi, G.; Divsalar, D. “Concatenated convolutional codes with interleavers,” IEEE Communications Magazine,Volume: 41 , Issue: 8 , Aug. 2003 Pages:102 - 109
  36. D. Divsalar, E. Biglieri, " Upper bounds to error probabilities of coded systems beyond the cutoff rate,” IEEE Transaction on Communications, December 2003.
  37. L. Li, D. Divsalar, S. Dolinar, "Iterative Demodulation, Demapping, and Decoding of Coded Non-Square QAM,", IEEE Communications Letters, January 2005.
  38. A. Abbasfar, D. Divsalar, K. Yao, “ Accumulate-Repeat-Accumulate Codes,’’ IEEE Transaction on Communications, April 2007.
  39. Simon, M.; Divsalar, D.; Some Interesting Observations for Certain Line Codes With Application to RFID,’’ IEEE Transactions on Communications, Volume 54, Issue 4, April 2006.
  40. K. Andrews, D. Divsalar, S. Dolinar, J. Hamkins, C. Jones, and F. Pollara,”The Development of Turbo and LDPC Codes for Deep Space Applications,” IEEE proceedings Vol. 95, No. 11, November 2007.
  41. D. Divsalar, S. Dolinar, C. Jones, and K. Andrews, Capacity Approaching Protograph Codes,” IEEE Journal of Selected Areas in Communications, Febraury 2009.
  42. M. Barsoum, B. Moision, M. Fitz, D. Divsalar, J. Hamkins, "Exit Function Aided Design of Iteratively Decodable Codes for Poisson PPM Channel", IEEE Transactions on Communications, December 2010.
  43. Shadi Abu-Surra, Dariush Divsalar, and William Ryan, "Enumerators for Protograph-Based Ensembles of LDPC and Generalized LDPC Codes," IEEE Transactions on Information Theory, Vol. 57, No. 2, pages 858 - 886, February 2011.
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