Johan Karlsson
Associate Professor, PhD

Johan Karlsson received an M.Sc. degree in Engineering Physics from KTH in 2003 and a Ph.D. in Optimization and Systems Theory from KTH in 2008. From 2009 to 2011, he was with Sirius International, Stockholm. From 2011 to 2013 he was working as a postdoctoral associate at the Department of Computer and Electrical Engineering, University of Florida. From 2013 he joined the Department of Mathematics, KTH, as an assistant professor and since 2017 he is working as an associate professor. His current research interests include inverse problems, methods for large scale optimization, and model reduction, for applications in remote sensing, signal processing, and control theory.

Phone: +46-(0)8-790 8440
Mail: johan.karlsson at math.kth.se


Workshops:


Teaching and student projects

Courses:

Previous Courses:

Master thesis projects:

(Email me if you currently study Optimization and Systems Theory and are interested in any of them)

Publications

Journal papers:

  1. G. Fanizza, J. Karlsson, A. Lindquist, and R. Nagamune: Passivity-preserving model reduction by analytic interpolation.
    Journal of linear algebra and its applications, vol. 425, pp. 608-633, September 2007.
  2. J. Karlsson and A. Lindquist: Stability-preserving rational approximation subject to interpolation constraints.
    IEEE Transactions on Automatic Control, vol. 53, pp. 1724-1730, August 2008. Full length version.
  3. T. Georgiou, J. Karlsson, and S. Takyar: Metrics for power spectra: an axiomatic approach.
    IEEE Transactions on Signal Processing, vol. 57, pp. 859-867, March 2009.
  4. J. Karlsson and A. Lindquist: On complexity constrained interpolation with interpolation points close to the boundary.
    IEEE Transactions on Automatic Control, vol. 54, pp. 1412-1418, June 2009.
  5. J. Karlsson, T. Georgiou, and A. Lindquist: The inverse problem of analytic interpolation with degree constraint and weight selection for control synthesis.
    IEEE Transactions on Automatic Control, vol. 55, pp. 405-418, February 2010.
  6. O. Ojowu Jr., J. Karlsson, J. Li, and Y. Liu: ENF extraction from digital recordings using adaptive techniques and frequency tracking.
    IEEE Transactions on Information Forensics & Security, vol. 7, pp. 1330-1338, August 2012.
  7. J. Karlsson and T. Georgiou: Uncertainty bounds for spectral estimation.
    IEEE Transactions on Automatic Control, vol 58, pp. 1659-1673, July 2013.
  8. K. Zhao, J. Liang, J. Karlsson, and J. Li: Enhanced multistatic active sonar signal processing.
    Journal of the Acoustical Society of America, vol. 134, pp. 300-311, July 2013.
  9. J. Karlsson, W. Rowe, L. Xu, G-O. Glentis, and J. Li: Fast missing data IAA with application to notched spectrum SAR.
    IEEE Transactions on Aerospace and Electronic Systems, vol. 50, pp. 959-971, July 2014.
  10. J. Karlsson, A. Lindquist, and A. Ringh: The multidimensional moment problem with complexity constraint.
    Integral Equations and Operator Theory, vol. 84, issue 3, pp. 395-418, March 2016.
  11. A. Ringh, J. Karlsson, and A. Lindquist: Multidimensional rational covariance extension with applications to spectral estimation and image compression.
    SIAM Journal on Control and Optimization, vol. 54, no. 4, pp. 1950-1982, 2016.
  12. E. Ringh, G. Mele, J. Karlsson, E. Jarlebring: Sylvester-based preconditioning for the waveguide eigenvalue problem.
    Accepted for publication in Linear Algebra and its Applications.
  13. Y. Chen, J. Karlsson, and T.T. Georgiou: The role of the time-arrow in mean-square estimation of stochastic processes.
    Submitted for publication.
  14. N. Shariati, D. Zachariah, J. Karlsson, and M. Bengtsson: Robust Optimal Power Distribution for Hyperthermia Cancer Treatment.
    Submitted for publication.
  15. J. Karlsson, A. Ringh: Generalized Sinkhorn iterations for regularizing inverse problems using optimal mass transport.
    Submitted for publication.
  16. A. Ringh, J. Karlsson, and A. Lindquist: Multidimensional rational covariance extension with approximate covariance matching.
    Submitted for publication.

Conference papers:

  1. J. Karlsson and T. Georgiou: Signal analysis, moment problems & uncertainty measures.
    IEEE Conference on Decision and Control, and IEEE European Control Conference, 2005.
  2. J. Karlsson and A. Lindquist: On complexity constrained interpolation with interpolation points close to the boundary.
    International Symposium on the Mathematical Theory of Networks and Systems, 2006.
  3. G. Fanniza, J. Karlsson, A. Lindquist, and R. Nagamune: A global analysis approach to passivity preserving model reduction.
    IEEE Conference on Decision and Control, 2006.
  4. J. Karlsson, T. Georgiou, and A. Lindquist: The inverse problem of analytic interpolation with degree constraint.
    IEEE Conference on Decision and Control, 2006.
  5. J. Karlsson and A. Lindquist: Stable rational approximation in the context of interpolation and convex optimization.
    IEEE Conference on Decision and Control, 2007.
  6. X. Jiang, J. Karlsson, and T. Georgiou: Phoneme segmentation based on spectral metrics.
    International Symposium on the Mathematical Theory of Networks and Systems, 2008.
  7. P. Enqvist and J. Karlsson: Minimal Itakura-Saito distance and covariance interpolation.
    International Symposium on the Mathematical Theory of Networks and Systems, 2008.
  8. J. Karlsson, T. Georgiou, and A. Lindquist: Weight selection for control synthesis with degree-constrained controllers.
    International Symposium on the Mathematical Theory of Networks and Systems, 2008.
  9. P. Enqvist and J. Karlsson: Minimal Itakura-Saito distance and covariance interpolation.
    IEEE Conference on Decision and Control, 2008.
  10. J. Karlsson, S. Takyar, and T. Georgiou: Transport metrics for power spectra.
    IEEE Conference on Decision and Control, 2008.
  11. J. Karlsson, T. Georgiou, and A. Lindquist: Weight selection for gap robustness with degree-constrained controllers.
    IEEE Conference on Decision and Control, 2008.
  12. W. Rowe, J. Karlsson, L. Xu, and J. Li: Untangling multipath returns in MIMO radar via waveform diversity.
    IEEE Sensor Array and Multichannel Signal Processing Workshop, 2012.
  13. J. Karlsson and P. Enqvist: Input-to-state covariances for spectral analysis: The biased estimate.
    International Symposium on the Mathematical Theory of Networks and Systems, 2012.
  14. J. Karlsson and T. Georgiou: Metric uncertainty for spectral estimation based on Nevanlinna-Pick interpolation.
    International Symposium on the Mathematical Theory of Networks and Systems, 2012.
  15. W. Rowe, J. Karlsson. Xu, G. Glentis, and J. Li: SAR imaging in the presence of spectrum notches via fast missing data IAA.
    SPIE Defense, Security, and Sensing, 2013.
  16. K. Zhao, J. Liang, J. Karlsson, and J. Li: Enhanced multistatic active sonar signal processing.
    IEEE International Conference on Acoustics, Speech, and Signal Processing, 2013.
  17. J. Karlsson, W. Rowe, L. Xu, G. Glentis, and J. Li: Fast missing data IAA by low rank completion.
    IEEE International Conference on Acoustics, Speech, and Signal Processing, 2013.
  18. W. Rowe, J. Karlsson, and J. Li: Error analysis of MIMO monopulse for tracking radar.
    International Radar Symposium, 2013.
  19. Y. Chen, J. Karlsson, and T. Georgiou: The role of past and future in estimation and the reversibility of stochastic processes.
    International Symposium on the Mathematical Theory of Networks and Systems, 2014.
  20. J. Karlsson, J. Li, and P. Stoica: Filter design with hard spectral constraints.
    European Signal Processing Conference, 2014.
  21. G.O. Glentis, J. Karlsson, A. Jakobsson, and J. Li: Efficient spectral analysis in the missing data case using sparse ML methods.
    European Signal Processing Conference, 2014.
  22. J. Karlsson and L. Ning: On robustness of L1-regularization methods for spectral estimation.
    IEEE Conference on Decision and Control, 2014.
  23. A. Sadeghian D. Lim, J. Karlsson, and J. Li: Automatic target recognition using discrimination based on optimal transport.
    IEEE International Conference on Acoustics, Speech, and Signal Processing, 2015.
  24. A. Ringh and J. Karlsson: A fast solver for the circulant rational covariance extension problem.
    IEEE European Control Conference, 2015.
  25. A. Gattami, E. Ringh, and J. Karlsson: Time localization and capacity of faster-than-Nyquist signaling.
    IEEE Globecom, 2015.
  26. A. Ringh, J. Karlsson, and A. Lindquist: The multidimensional circulant rational covariance extension problem: solutions and applications in image compression.
    IEEE Conference on Decision and Control, 2015.
  27. J. Karlsson, P. Enqvist, and A. Gattami: Confidence Assessment for Spectral Estimation based on Estimated Covariances.
    IEEE International Conference on Acoustics, Speech, and Signal Processing, 2016.
  28. A. Ringh, J. Karlsson, and A. Lindquist: Multidimensional Rational Covariance Extension with Approximate Covariance Matching.
    International Symposium on the Mathematical Theory of Networks and Systems, 2016.
  29. J. Karlsson and L. Ning: Super-Resolution methods and Metric Uncertainty via Optimal Transport.
    International Symposium on the Mathematical Theory of Networks and Systems, 2016.
  30. F. Elvander, S. Adalbjörnsson, J. Karlsson, and A. Jakobsson: Using optimal transport for estimating inharmonic pitch signals.
    IEEE International Conference on Acoustics, Speech, and Signal Processing, 2017.
  31. A. Ringh, J. Karlsson, and A. Lindquist: Further results on multidimensional rational covariance extension with application to texture generation.
    IEEE Conference on Decision and Control, 2017.

Theses: