<Publications>

Research

List of publications

Journal Papers and Book Chapters

Under Review
52. R. Balan, E. Tsoukanis, M. Wellershoff, Stability of sorting based embeddings, arXiv:2410.05446 [math.FA] [cs.LG]
51. R. Balan, F. Jiang, Factorization of positive-semidefinite operators with absolutely summable entries, arXiv:2409.20372 [math.FA]
50. K. Linehan, R. Balan, Approximation of the Proximal Operator of the linf Norm using a Neural Network, arXiv:2408.11211 [math.NA, cs.LG]
49. R. Balan, E. Tsoukanis, G-Invariant Representations using Coorbits: Injectivity Properties, arXiv:2310.16365 [math.RT]
48. R. Balan, E. Tsoukanis, G-Invariant Representations using Coorbits: Bi-Lipschitz Properties, arXiv:2308.11784 [ math.RT]
47. R. Balan, N. Haghani, M. Singh, Permutation Invariant Representations with Applications to Graph Deep Learning, arXiv:2203.07546 [math.FA]
Published
46. B. Li, N. Li, Z. Wang, R. Balan, T. Ernst, Simultaneous multislice EPI prospective motion correction by real-time receiver phase correction and coil sensitivity map interpolation, Magnetic Resonance in Medicine, DOI: 10.1002/mrm.29789, 13 July 2023 Wiley Library, .pdf.
45. A. Lauziere, R. Christensen, H. Shroff, R. Balan, An Exact Hypergraph Matching Algorithm for Posture Identification in Embryonic C. elegans, PLOS ONE 17(11), (2022) open access.
44. R. Balan, C.B. Dock, Lipschitz Analysis of Generalized Phase Retrievable Matrix Frames, .pdf; SIAM Journal on Matrix Analysis and Applications (SIMAX), vol. 43(3), 1518 - 1571 (2022), doi: 10.1137/21M1435446
43. R. Balan, K.A. Okoudjou, M. Rawson, Y. Wang, R. Zhang, Optimal l1 Rank One Matrix Decomposition, .pdf; in "Harmonic Analysis and Applications", Rassias M., Ed. Springer (2021)
42. R. Balan, D. Dutkay, D. Han, D. LArson, F. Luef, A Duality Principle for Groups II: Multi-frames Meet Super-frames, JFAA vol. 26, 83 (2020) doi: 10.1007/s00041-020-09792-0, Open source
41. A.W. Bohannon, V.J. Lawhern, N.R. Waytowich, R.V. Balan, The Autoregressive Linear Mixture Model: a Time-Series Model for an Instantaneous Mixture of Network Processes, IEEE Trans. on Sig.Proc., vol. 68, 4481 - 4496 (2020) doi: 10.1109/TSP.2020.3012946 .pdf
40. D. Zou, R. Balan, M. Singh, On Lipschitz Bounds of General Convolutional Neural Networks, IEEE Trans.on Info.Theory, vol. 66(3), 1738--1759 (2020) doi: 10.1109/TIT.2019.2961812 .pdf
39. A.W. Bohannon, B.M. Sadler, R.V. Balan, A Filtering Framework for Time-Varying Graph signals, .pdf in "Vertex-Frequency Analysis of Graph Signals", L.Stankovic and E.Sejdic Eds., Springer Signals and Communication Technology series (2019) https://doi.org/10.1007/978-3-030-03574-7
38. R. Balan, K. Okoudjou, A. Poria, On a Feichtinger Problem, Operators and Matrices vol. 12(3), 881-891 (2018) http://dx.doi.org/10.7153/oam-2018-12-53 , .pdf
37. R. Balan, M. Singh, D. Zou, Lipschitz Properties for Deep Convolutional Networks, .pdf, available online arXiv:1701.05217 [cs.LG], Contemporary Mathematics 706, 129-151 (2018) http://dx.doi.org/10.1090/conm/706/14205
36. R. Balan, M. Begue, C. Clark, K. Okoudjou, Optimization methods for frame conditioning and application to graph Laplacian scaling, .pdf, available online arXiv:1609.02233 [math.FA], "Novel methods in harmonic analysis with applications to numerical analysis and data processing", Lecture Notes ANHA Series, I.Pesenson and all Eds., Birkhauser 2017.
35. R. Balan, D. Zou, On Lipschitz Analysis and Lipschitz Synthesis for the Phase Retrieval Problem, .pdf, available online arXiv:1506.02092 [math.FA],Linear Algebra and Applications 496, 152-181 (2016).
34. R. Balan, Frames and Phaseless Reconstruction, .pdf file and online 1601.0345v1 [math.FA], AMS Short Course at the Joint Mathematics Meetings, San Antonio, January 2015. Proceedings of Symposia in Applied Mathematics 73 175-199 (2016) http://dx.doi.org/10.1090/psapm/073/00632
33. R. Balan, D. Zou, On Lipschitz Inversion of Nonlinear Redundant Representations, .pdf file, Contemporary Mathematics 650, "Trends in Harmonic Analysis and Its Applications", 15-22, 2015.
32. R. Balan, Stability of Frames Which Give Phase Retrieval, .pdf , Houston Journal of Mathematics 43(3), 905-918 (2017).
31. R. Balan, Reconstruction of Signals from Magnitudes of Redundant Representation: The Complex Case, available online arXiv:1304.1839v1 [math.FA] , Apr. 2013, Foundations of Computational Mathematics, vol. 16(3), (2016) 677-721.
30. R. Balan, Y. Wang, Invertibility and Robustness of Phaseless Reconstruction, available online arXiv:1308.4718 [math.FA] , 21 Aug 2013, Appl. Comp. Harm. Anal. vol. 38, no. 3, (2015) 469-488.
29. R. Balan, J.G. Christensen, I.A. Krishtal, K.A. Okoudjou, J.L. Romero, Multi-window Gabor frames in amalgam space, Math. Res. Lett., vol. 21, no. 1, (2014) 55-69 link
28. R.Balan, P.Casazza, Z.Landau, Redundancy of Localized Frames, Israel Journal of Mathematics vol. 185 (2011) 445-476 .pdf ref
27. R.Balan, I.Krishtal, An Almost Periodic Noncommutative Wiener's Lemma, Journal of Mathematical Analysis and Applications, vol. 370, no. 2 (2010) 339-349 .pdf ref
26. R.Balan, B.G.Bodmann, P.G.Casazza, D.Edidin, Painless Reconstruction from Magnitudes of Frame Coefficients, J.Fourier Anal..Appl., vol. 15, no. 4 (2009) 488-501 .pdf ref,
25. F.Meshkati, V.Poor, S.Schwartz, R.Balan, Energy-Efficient Resource Allocation in Wireless Networks with Quality-of-Service Contraints, IEEE Trans. on Communications vol. 57, no. 11 (2009) .pdf
24. R. Balan, An Extension of Barbashin-Krasovskii-LaSalle Theorem to a Class of Nonautonomous Systems, Nonlinear Dynamics and Systems Theory, 8(3), 255-268 (2008) .pdf
23. R.Balan, A Noncommutative Wiener Lemma and A Faithful Tracial State on Banach Algebra of Time-Frequency Operators, Trans.Amer.Math.Soc., vol. 360, no. 7, (2008) 3921-3941 TAMS site, .pdf or .pdf (ESI preprint)
22. R.Balan, Z.Landau, Measure Functions for Frames, Journal of Functional Analysis, 252 (2007), 630-676, .pdf, DOI
21. R.Balan, P.Casazza, D.Edidin, Equivalence of Reconstruction from the Absolute Value of the Frame Coefficients to a Sparse Representation Problem, IEEE Sig. Proc. Letters vol.14, no.5 (2007), 341-343 .pdf
20. R.Balan, P.Casazza, D.Edidin, G.Kutyniok, A New Identity for Parseval Frames, Proc. Amer. Math. Soc., 135 (2007), 1007-1015 .pdf ref
19. R.Balan, P.Casazza, C.Heil, Z.Landau, Density, Overcompleteness, and Localization of Frames. II Gabor Frames, J.Fourier Anal. Applic., Vol.12, No.3, (2006) 309-344 .pdf ref
18. R.Balan, P.Casazza, C.Heil, Z.Landau, Density, Overcompleteness, and Localization of Frames. I Theory, J.Fourier Anal. Applic., Vol.12, No.2, (2006) 105-143, .pdf ref
17. R.Balan, P.Casazza, D.Edidin, On Signal Reconstruction without Noisy Phase, Appl. Comp. Harm. Anal., 20 (2006) 345-356 .pdf ref
16. S.Rickard, R.Balan, V.Poor, S.Verdu, Canonical time-frequency, time-scale, and frequency-scale representations of time-varying channels, J. Comm. Infor. Syst. vol.5, no.5 (2005) 1-30 .pdf
15. R.Balan, J.Rosca, S.Rickard, Equivalence Principle for Optimization of Sparse versus Low-Spread Representations for Signal estimation in Noise, International Journal in Imaging Systems and Technology vol.15, no.1, (2005) 10-17 .pdf
14. R.Balan, P.Casazza, C.Heil, Z.Landau, Excesses of Gabor Frames, Appl. and Comp. Harm. Anal., vol. 14, (2003) 87-106 .pdf ref
13. R.Balan, P.Casazza, C.Heil, Z.Landau, Deficits and Excesses of Frames, Advances and Computational Mathematics, vol. 18, (2003) 93-116 .pdf
12. R.Balan, I.Daubechies, Optimal Stochastic Approximations and Encoding Schemes using Weyl-Heisenberg Sets, chapter in "Gabor Analysis: Theory and Applications", Eds. H.Feichtinger and T.Strohmer, Birkhauser 2002 .pdf
11. R.Balan, I.Daubechies, V.Vaishampayan, The Analysis and Design of Windowed Fourier Frame based Multiple Description Source Coding Schemes, in IEEE Trans.on IT, vol.46, no.7, (2000) 2491-2537 .pdf
10. R.Balan, G.Taubin, 3D Mesh Geometry Filtering Algorithms for Progressive Transmission Schemes, Computer-Aided Design, vol.32, no.13, (2000) 825-846 .pdf ref
9. R.Balan, Density and Redundancy of the Noncoherent Weyl-Heisenberg Superframes, Contemporary Mathematics , AMS Providence R.I. (1999) .pdf
8. R.Balan, Equivalence Relations and Distances between Hilbert Frames, Proceedings of the AMS, vol.127 no.8, (1999) 2353-2366 .pdf
7. R.Balan, Extensions of No-Go Theorems to Many Signal Systems, Contemporary Mathematics 216, AMS Providence R.I. (1998), 3-14 .pdf
6. R.Balan, An Uncertainty Inequality for Wavelet Sets, Applied and Computational Harmonic Analysis, Vol.5, no.1, (1998) 106-108 .pdf ref
5. R.Balan, Stability Theorems for Fourier Frames and Wavelet Riesz Bases, Journal of Fourier Analysis and Applications, Vol.3, no.5, (1997), 499-504 .pdf
4. R.Balan, Horseshoe and Analytic Nonintegrability of a Spinless Axialsymmetric Rigid Body in Central Newtonian Field, Celestial Mechanics and Dynamics Astronomy, vol.63 (1995), 59-79 .pdf
3. R.Balan, D.Aur, An On-Line Robust Stabilizer, Journal in Guidance, Control and Dynamics, (18) no.3, (1995), 642-644 .pdf
2. R.Balan, Homogeneous Polynomial Approximations of Nonlinear Control Systems, Revue Roumaine de Science Techniques, serie Electrotechnique et Energetique, (39) no.4, (1994), 503-511 .pdf
1. R.Balan, A Note about Integrability of Distributions with Singularities, Bollettino U.M.I. (7) 8-A (1994), 335-344 .pdf

Peer Reviewed Conference Proceedings

59. R. Balan, E. Tsoukanis, Relationships between the Phase Retrieval Problem and Permutation Invariant Embeddings, SampTA 2023 paper
58. X. Xiao, D. Cao, R. Yang, G. Gupta, G. Liu, C. Yin, R. Balan, P. Bogdan, Coupled Multiwavelet Neural Operator learning for coupled PDEs, accepted at ICLR 2023 paper
57. S. Sadheekh, C.B. Dock, T. Jain, R. Balan, M. Singh, VQ-FLOWS: VECTOR QUANTIZED LOCAL NORMALIZING FLOWS, Proceedings of UAI 2022, August 2022 paper, poster, spotlight presentation
56. G. Gupta, X. Xiao, R. Balan, P. Bogdan, NON-LINEAR OPERATOR APPROXIMATIONS FOR INITIAL VALUE PROBLEMS, Proceedings of ICLR 2022, paper,
55. N. Haghani, M. Singh, R. Balan, Graph Regressing and Classification using Permutation Invariant Representations, AAAI-GCLR March 2022, paper, Poster
54. ISMRS 2022 Extended Abstract: CRLB in DNN
52.53. ISMRM 2021 Extended Abstracts: MGRAPPA , MC-NET
51. R. Balan, N. Haghani, Discrete optimizations using graph convolutional networks, Proc. SPIE 11138 Wavelets and Sparsity XVIII, San Diego, August 2019 .pdf
50. R. Balan, D. Bekkerman, The Cramer-Rao Lower Bound in the Phase Retreival Problem, SampTA 2019, Bordeaux, France, July 2019 .pdf
49. R. Balan, The Fisher Information Matrix and the CRLB in a Non-AWGN Model for the Phase Retrieval Problem, SampTA 2015, Washington DC, May 2015 .pdf
48. Yenming M. Lai, R. Balan, H. Claussen, J. Rosca, Optimal Beampattern Design For Very Large Sensor Arrays With Sparse Sampling, 47th Asilomar Conference on Signals, Systems and Computers, Pacific Grove, CA, Nov. 2013 .pdf
47. Yenming M. Lai, R. Balan, H. Claussen, J. Rosca, Broadband Sensor Location Selection using Convex Optimization In Very Large Scale Arrays, WASPAA 2013 Workshop, New Paltz, NY, Oct. 2013 .pdf
46. R. Balan, Stability of Phase Retrievable Frames, SPIE Wavelets Applications in Signal and Image Processing XII, San Diego Aug. 2013 .pdf
45. M.Scharrenbroich, M.Zatman, R.Balan, Performance of a Practical Two-Step Detector for Non-fluctuating Targets, Proceedings SAM 2012, .pdf
44. M.Scharrenbroich, M.Zatman, R.Balan, Cooperative Networked Radar: The Two-Step Detector", 45th Asilomar Conference on Signals, Systems and Computers, November 9 2011, .pdf
43. R.Balan, On Signal Reconstruction from Its Spectrogram, CISS 2010, Princeton, NJ, March 2010 .pdf
42. R.Balan, A Nonlinear Reconstruction Algorithm from Absolute Value of Frame Coefficients for Low Redundancy Frames, SampTA, Marseille, France, May 2009 .pdf
41. R.Balan, Information Theory based Estimator of the Number of Sources in a Sparse Linear Mixing Model, CISS 2008, Princeton, NJ, March 2008 .pdf
40. B.G.Bodmann, P.Casazza, R.Balan, Frames for Linear Reconstruction without Phase, CISS 2008, Princeton, NJ, March 2008 .pdf
39. R.Balan, Estimator for Number of Sources using a Minimum Description Length Criterion for Blind Sparse Source Mixtures, ICA 2007, London, UK, September 2007 .pdf
38. R.Balan, B.G.Bodmann, P.G.Casazza, D.Edidin, Fast Algorithms for Signal Reconstruction without Phase, SPIE Wavelets Applications in Signal and Image Processing XII, San Diego Aug. 2007 .pdf
37. R.Balan, B.G.Bodmann, P.G.Casazza, D.Edidin, Painless Reconstruction from Magnitudes of Frame Coefficients, SPIE Wavelets Applications in Signal and Image Processing XII, San Diego Aug. 2007 .pdf
36. N.Fan, J.Rosca, R.Balan, Speech Noise Estimation using Enhanced Minima Controlled Recursive Averaging, Proceedings ICASSP 2007, Hawaii USA, April 2007..pdf
35. R.Balan, J.Rosca, MAP Source Separation using Belief Propagation Networks, 40th Asilomar Conference on Signals, Systems and Computers, Pacific Grove, CA, October 2006 .pdf
34. F.Meshkati, H.V.Poor, S.C.Schwartz, R.Balan, Energy-Efficient Power and Rate Control with QoS Constraints: A Game-Theoretic Approach, Int. Wireless Comm. Mobile. Comp. (IWCMC) Conf. 2006 - Cross-Layer Design and Protocols, Vancouver, Canada, July 2006 .pdf
33. R.Balan, J.Rosca, Source Separation using Sparse Discrete Prior Models, ICASSP 2006, Toulouse, France, May 2006 .pdf
32. R.Balan, J.Rosca, Source Convolutive Demixing with Sparse Discrete Prior Models for Markov Sources, ICA 2006, Charleston SC USA, May 2006 .pdf
31. P.Bogdan, R.Balan, J.Rosca, Statistical Signal Processing for Novelty Detection, CSCS 2005, Bucharest, Romania, May 2005 .pdf
30. N.Fan, J.Rosca, R.Balan, Speaker Identification with Combined Threshold Identification Front-End & UBM, 4th IEEE Workshop on Automatic Identification Advanced Technology (AutoID 2005), Buffalo NY 2005 .pdf
29. P.Casazza, R.Balan, D.Edidin, G.Kutyniok, Decomposition of frames and a new frame identity in SPIE Wavelets Applications in Signal and Image Processing XI, vol.5914 , (2005)
28. R.Balan, P.Casazza, C.Heil, Z.Landau, Excess of Parseval frames in SPIE Wavelets Applications in Signal and Image Processing XI, vol.5914 , (2005) .pdf
27. R.Balan, P.Casazza, D.Edidin, On Signal Reconstruction from absolute value of frame coefficients in SPIE Wavelets Applications in Signal and Image Processing XI, vol.5914 , (2005).pdf
26. B.Grundlehner, J.Lecocq, R.Balan, J.Rosca, Performance Assessment Method for Speech Enhancement Systems, SPS-DARTS 2005, Antwerp, Belgium, April 2005 .pdf
25. N.Fan, R.Balan, J.Rosca, Comparison of Wavelet and FFT based Single Channel Speech Signal Noise Reduction Techniques, in Proceedings of SPIE Industrial Applications of Wavelets Conference 2004, Philadelphia, PA, October 2004 .pdf
24. R.Balan, H.V.Poor, S.Rickard, S.Verdu, Time-Frequency and Time-Scale Canonical Representations of Doubly Spread Channels, in Proceedings of EUSIPCO 2004, Vienna, Austria, September 2004 .pdf
23. L.Hong, J.Rosca, R.Balan, Bayesian Single Channel Speech Enhancement Exploiting Sparseness in the ICA Domain, in Proceedings of EUSIPCO 2004, Vienna, Austria, September 2004 .pdf
22. R.Balan, J.Rosca, C.Beaugeant, V.Gilg, T.Fingscheidt, Generalized Stochastic Principle for Microphone Array Speech Enhancement and Applications to Car Environments, in Proceedings of EUSIPCO 2004, Vienna, Austria, September 2004 .pdf
21. J.Rosca, C.Borss, R.Balan, Generalized Sparse Signal Mixing Model and Application to Noisy Blind Source Separation, in Proceedings of ICASSP 2004, Montreal, Canada, May 2004 .pdf
20. S.Rickard, C.Fearon, R.Balan, J.Rosca, MINUET: Musical Interference Unmixing estimation Technique, in Proceedings of CISS 2004, Princeton NJ, March 2004 .pdf
19. R. Balan, Z. Landau, Measure and Redundancy of Frames, in Proceedings of SPIE 2003, San Diego, CA 2003. .pdf
18. J.Rosca, R.Balan, C.Beaugeant, Multi-Channel Psychoacoustically Motivated Speech Enhancement, in Proceedings of ICASSP 2003, Hong Kong China, April 2003 .pdf
17. R.Balan, J.Rosca, S.Rickard, Scalable Non-Square BSS in the Presence of Noise, in Proceedings of ICASSP 2003, Hong Kong China, April 2003 .pdf
16. J.Rosca, R.Balan, S.Rickard, Scalable Audio Source Separation in the Presence of Noise, in Proceedings of DAGA 2003, Aachen, Germany, June 2003
15. R.Balan, J.Rosca, S.Rickard, Non-square BSS under Coherent Noise by Beamforming and Time-Frequency Masking, in Proceedings of ICA 2003, Nara Japan, April 2003 .pdf
14. S.Rickard, R.Balan, J.Rosca, Blind Source Separation based on Space-Time-Frequency Diversity, in Proceedings of ICA 2003, Nara Japan, April 2003 .pdf
13. R.Balan, J.Rosca, S.Rickard, A Stochastic Speech Model Supporting W-Disjoint Orthogonality, in Proceedings of 2003 CISS, Baltimore MD, March 2003 .pdf
12. J.Rosca, R.Balan, N.Fan, C.Beaugeant, V.Gilg, Multichannel Voice Detection in Adverse Environments, in Proceedings of EUSIPCO 2002, Toulouse FRANCE, September 2002 .pdf
11. R.Balan, J.Rosca, Microphone Array Speech Enhancement by Bayesian Estimation of Spectral Amplitude and Phase, in Proceedings of IEEE Sensor Array and Multichannel Signal Processing Workshop, Rosslyn VA, Aug. 2002 .pdf
10. S.Aalburg, C.Beaugeant, S.Stan, T.Fingscheidt, R.Balan, J.Rosca, Single- and Two-Channel Noise Reduction For Robust Speech Recognition in Car, in Proceedings of ISCA Workshop, GERMANY, June 2002 .pdf
9. R.Balan, J.Rosca, S.Rickard, Robustness of Parametric Source Demixing in Echoic Environments, in the Proceedings of the 3rd ICA and BSS Conference, San Diego, CA, December 2001 .pdf
8. J.Rosca, N.Fan, R.Balan, Real-Time Audio Source Separation by Delay and Attenuation Compensation in the Time Domain, in the Proceedings of the 3rd ICA and BSS Conference, San Diego, CA, December 2001 .pdf
7. S.Rickard, R.Balan, J.Rosca, Real-Time Time-Frequency Based Blind Source Separation, in the Proceedings of the 3rd ICA and BSS Conference, San Diego, CA, December 2001 .pdf
6. J.Rosca, S.Sudarsky, R.Balan, D.Comaniciu, Mobile Interaction with Remote Worlds: The Acoustic Periscope, in the Proceedings of IJCAI 2001 .pdf
5. R.Balan, J.Rosca, Statistical Properties of STFT Ratios for Two Channel Systems and Applications to Blind Source Separation, in the Proceedings of 2nd ICA and BSS Conference 2000, Helsinki, FINLAND, June 2000 .pdf
4. R.Balan, Topological Obstructions to Localization Results in SPIE Wavelets Applications in Signal and Image Processing VIII, vol. 4478, (2001) 184-192 .pdf
3. R.Balan, Multiplexing of Signals using Superframes in SPIE Wavelets Applications in Signal and Image Processing VIII, vol.4119 , (2000) 118-129 .pdf
2. R.Balan, J.Rosca, S.Rickard, J.O�Ruanaidh, The Influence of Windowing on Time Delay Estimates, in the Proceedings of the CISS 2000, Princeton NJ, March 15-17 2000 .pdf
1. R.Balan, A.Jourjine, J.Rosca, AR processes and sources can be reconstructed from degenerate mixtures, in the Proceedings of the First International Workshop on Independent Component Analysis and Signal Separation, Aussois France, January 11-15 1999, 467-472 .pdf (see also TR 703 below)

Books and Edited Volumes

1. Excursions in Harmonic Analysis , vol.1, T.D. Andrews, R. Balan, J.J. Benedetto, W. Czaja, K.A. Okoudjou Eds., Birkhauser 2013.
2. Excursions in Harmonic Analysis , vol.2, T.D. Andrews, R. Balan, J.J. Benedetto, W. Czaja, K.A. Okoudjou Eds., Birkhauser 2013.
3. Excursions in Harmonic Analysis , vol.3, R. Balan, M. Begue, J.J. Benedetto, W. Czaja, K.A. Okoudjou Eds., Birkhauser 2015.
4. Excursions in Harmonic Analysis , vol.4, R. Balan, M. Begue, J.J. Benedetto, W. Czaja, K.A. Okoudjou Eds., Birkhauser 2015.
5. Excursions in Harmonic Analysis , vol.5, R. Balan, J.J. Benedetto, W. Czaja, M. Dellatorre, K.A. Okoudjou Eds., Birkhauser 2017.

Patents

1. Separation of AR Sources from their Single Channel Measurement, US Patent # 6,343,268, January 29, 2002
2,3.Optimal ratio estimator for multisensor systems, US Patent # 6,577,966, June 10, 2003, and US Patent # 6,868,365, Mar 15, 2005
4. Method of denoising signal mixtures, US Patent # 6,901,363, May 31, 2005
5. Online Blind Source Separation�, US Patent # 6,954,494, October 11, 2005
6,7. Method and Apparatus for Noise Filtering, US Patent # 6,952,482, October 4, 2005, and US Patent # 7,110,944, September 19, 2006
8. Apparatus and Method for Estimating the Direction of Arrival of a Source Signal using a Microphone Array, US Patent # 7,084,801, August 1, 2006
9. Real-Time Audio Source Separation by Delay and Attenuation Compensation in the Time Domain, US Patent # 7,088,831, August 8, 2006
10. Multichannel voice detection in adverse environments, US Patent# 7,146,315, December 5, 2006
11. System and method for remotely experiencing a virtual environment, US Patent# 7,149,691, December 12, 2006
12. Multi-channel speech enhancement system and method based on psychoacoustic masking effects, US Patent# 7,158,933, January 2, 2007
13. System and Method for Adaptive Multi-Sensor Arrays, US Patent# 7,218,741, May 15, 2007
14. Method for eliminating an unwanted signal from a mixture via time-frequency masking, US Patent# 7,302,066, November 27, 2007
15. System and method for nonlinear signal enhancement that bypasses a noisy phase of a signal, US Patent# 7,392,181, June 24, 2008
16. System and method for non-square blind source separation under coherent noise by beamforming and time-frequency masking, US Patent# 7,474,756, January 6, 2009
17. Method and Apparatus to Inspect Wireless Traffic and Mitigate Packet Elimination for Wireless Saturation Avoidance, World Patent WO 2010/002729 A1, January 7, 2010
18. Methods and apparatus for estimating collision probability in a wireless network, US Patent# 7,839,793, November 23, 2010
19. Method and apparatus to inspect wireless traffic and mitigate packet elimination for wireless saturation avoidance, US Patent# 8,045,471, October 25, 2011
20. Method for congestion detection in packet transmission networks, US Patent# 8,737,213 , May 27, 2014
21. Method and Apparatus for Acoustic Area Monitoring by Exploiting Ultra Large Scale Arrays of Microphones, US Patent #9,264,799, February 16, 2016
22. Broadband Sensor Location Selection Using Convex Optimizaton in Very Large Scale Arrays, US Patent#9,615,172, April 4, 2017
23. Simultaneous solution for sparsity and filter responses for a microphone network, US Patent#10,206,035, February 12, 2019
24. Systems and methods for optimized computer vision using deep neural networks and Litpschitz analysis, US Patent#10,839,253, November 17, 2020
25. Systems and Methods for Generating Permutation Invariant Representations for Graph Convolutional Networks, US Patent#TBD, TBD

Other Publications

13. A.W. Bohannon, J.O. Garcia, J.M. Vettel, R.V. Balan, Estimating Functional Connectivity from fMRI Data Using a Frequency-Sparse Multivariate Autoregressive Model, .pdf, Poster 2018.
12. A.W. Bohannon, B.M. Sadler, R.V. Balan, Learning Flexible Representations of Stochastic Processes on Graphs, .pdf Poster 2018.
11. R. Balan, The Cramer-Rao Lower Bound in the Phase Retrieval Problem, .pdf
10. R. Balan, Nonlinear Frame Analysis and Phaseless Reconstruction, Lecture Notes for the Summer Graduate Program "Harmonic Analysis and Applications", at UMD, July 20-August 7, 2015 .pdf
9. L.Driskell, Y.Gong, X.Hu, R.Jain, M.Nkengla, 802.11 WLAN MAC Layer Modeling, IMA 2007 Modeling Workshop .pdf
8. Bogdan Alexandru Vasile, Audio-Video Sensor Fusion based Person Recognition System, Universitatea "Politehnica" Bucharest, 2006 .pdf
7. Matei-Eugen Vasile, WLAN-based Wireless Medium Surveillance System for Location Estimation, University "Politehnica" Bucharest, 2006 .pdf
6. R.Balan, J.Rosca, A Spectral Power Factorization, Siemens Corporate Research TR 703 2001 .pdf
5. R.Balan, Multiframes and Multi Riesz Bases: I. The General Theory and Weyl-Heisenberg Case, Princeton University 1997 .ps
4. R.Balan, V.Ionescu, Absolute Stability Criteria for Nonlinear Affine Systems: A Kalman-Yakubovick-Popov Type Approach, University "Politechnica" of Bucharest 1996 .pdf
3. R.Balan, Robustness Properties of Nonlinear Systems: Absolute Stability of Linear Systems, University "Politehnica" of Bucharest, 1996 .pdf
2. R.Balan, An Extension of Barbashin-Krasovski-LaSalle Theorem to a Class of Nonautonomous Systems, Princeton University, 1995 .pdf
1. R.Balan, Codistributions with Singularities, Polytechnic Institute of Bucharest, 1992 .pdf

Preprints available on Arxiv

1. R. Balan, Reconstruction of Signals from Magnitudes of Redundant Representations, available online arXiv:1207.1134[math.FA] , July 2012.

Acknowledgment and Disclaimer

This material is based upon work supported in part by the National Science Fundation under Grants No. DMS-0807896 , DMS-1109498 , DMS-1413249 , DMS-1816608 , DMS-2108900.
"Any opinion, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the viewes of the National Science Foundation (NSF)."

Some works have also been partially supported by ARO under contract no. W911NF-16-1-0008. Additional support provided by Simons Foundation, LTS, Siemens, and Verisk.