Publications

R. Smarandache and D. G. M. Mitchell, “The Number of Cycles of Bi-regular Tanner Graphs in Terms of the Eigenvalues of the Adjacency Matrix,” Submitted to IEEE Transactions on Information Theory, Dec. 2025.

R. Smarandache, D. G. M. Mitchell, and A. Gomez-Fonseca, “Structural Analysis of Generalized Quasi-Cyclic LDPC Codes: Rank, Design, and Generator Matrices,” IEEE Transactions on Information Theory, vol. 72, no. 1, pp. 253–267; online Oct. 2025, physical volume Jan. 2026.

A. Gomez-Fonseca, R. Smarandache, and D. G. M. Mitchell, “An Efficient Strategy to Count Cycles in the Tanner Graph of Quasi-Cyclic LDPC Codes,” IEEE Journal on Selected Areas in Information Theory, vol. 4, pp. 499–513, 2023.

R. Smarandache and D. G. M. Mitchell, “A Unifying Framework to Construct QC-LDPC Tanner Graphs of Desired Girth,” IEEE Transactions on Information Theory, vol. 68, no. 9, pp. 5802–5822, Sept. 2022.

S. Mo, L. Chen, D. J. Costello, Jr., D. G. M. Mitchell, and R. Smarandache, “Designing Protograph-Based Quasi-Cyclic Spatially Coupled LDPC Codes With Large Girth,” IEEE Transactions on Communications, vol. 68, no. 9, pp. 5326–5337, Sept. 2020.

D. Napp and R. Smarandache, “Constructing Strongly-MDS Convolutional Codes with Maximum Distance Profile,” Advances in Mathematics of Communications, vol. 10, no. 2, pp. 275–290, 2016.

D. G. M. Mitchell, R. Smarandache, and D. J. Costello, Jr., “Quasi-Cyclic LDPC Codes Based on Pre-lifted Protographs,” IEEE Transactions on Information Theory, vol. 60, no. 10, pp. 5856–5874, Oct. 2014.

D. J. Costello, Jr., L. Dolecek, T. E. Fuja, J. Kliewer, D. G. M. Mitchell, and R. Smarandache, “Spatially Coupled Sparse Codes on Graphs — Theory and Practice,” IEEE Communications Magazine, vol. 52, no. 7, pp. 168–176, July 2014.

M. Haenggi and R. Smarandache, “Diversity Polynomials for the Analysis of Temporal Correlations in Wireless Networks,” IEEE Transactions on Wireless Communications, vol. 12, no. 11, pp. 5940–5951, Nov. 2013.

A. G. Dimakis, R. Smarandache, and P. O. Vontobel, “LDPC Codes for Compressed Sensing,” IEEE Transactions on Information Theory, vol. 58, no. 5, pp. 3093–3114, May 2012.

R. Smarandache and P. O. Vontobel, “Quasi-Cyclic LDPC Codes: Influence of Proto- and Tanner-Graph Structure on Minimum Hamming Distance Upper Bounds,” IEEE Transactions on Information Theory, vol. 58, no. 2, pp. 585–607, Feb. 2012.

V. Tomas, J. Rosenthal, and R. Smarandache, “Decoding of Convolutional Codes over the Erasure Channel,” IEEE Transactions on Information Theory, vol. 58, no. 1, pp. 90–108, 2012.

A. E. Pusane, R. Smarandache, P. O. Vontobel, and D. J. Costello, Jr., “Deriving Good LDPC Convolutional Codes from LDPC Block Codes,” IEEE Transactions on Information Theory, vol. 57, no. 2, pp. 835–857, 2011.

R. Smarandache, A. Pusane, P. O. Vontobel, and D. J. Costello, Jr., “Pseudo-Codeword Performance Analysis for LDPC Convolutional Codes,” IEEE Transactions on Information Theory, vol. 55, no. 6, pp. 2577–2598, 2009.

R. Hutchinson, R. Smarandache, and J. Trumpf, “Superregular Matrices and the Construction of Convolutional Codes Having a Maximum Distance Profile,” Linear Algebra and Its Applications, vol. 428, nos. 11–12, pp. 2585–2596, 2008.

R. Smarandache and P. O. Vontobel, “Pseudo-codeword Analysis of Tanner Graphs from Projective and Euclidean Planes,” IEEE Transactions on Information Theory, vol. 53, no. 7, pp. 2376–2393, 2007.

R. Smarandache and M. Wauer, “Bounds on the Pseudo-weight of Minimal Pseudo-codewords of Projective Geometry Codes,” Contemporary Mathematics, Algebra and Its Applications, vol. 419, pp. 285–296, 2006.

H. Glüsing-Lüerßen, J. Rosenthal, and R. Smarandache, “Strongly MDS Convolutional Codes,” IEEE Transactions on Information Theory, vol. 52, no. 2, pp. 584–598, 2006.

R. Hutchinson, J. Rosenthal, and R. Smarandache, “Convolutional Codes with Maximum Distance Profile,” Systems & Control Letters, vol. 54, no. 1, pp. 53–63, 2005.

R. Smarandache, H. Glüsing-Lüerßen, and J. Rosenthal, “Constructions for MDS-Convolutional Codes,” IEEE Transactions on Information Theory, vol. 47, no. 5, pp. 2045–2049, 2001.

R. Smarandache, “Unit Memory Convolutional Codes with Maximum Distance,” Codes, Systems and Graphical Models, IMA Volumes in Mathematics and its Applications, vol. 123, pp. 381–396, 2001.

J. Rosenthal and R. Smarandache, “Maximum Distance Separable Convolutional Codes,” Applicable Algebra in Engineering, Communication and Computing, vol. 10, no. 1, pp. 15–32, 1999.

R. Smarandache, A. Gomez-Fonseca, and D. G. M. Mitchell, “Generalized Quasi-Cyclic LDPC Codes: Design and Efficient Encoding,” 2024 IEEE International Symposium on Information Theory (ISIT), Athens, Greece, pp. 434–439, 2024.

A. Gomez-Fonseca, R. Smarandache, and D. G. M. Mitchell, “A Low Complexity PEG-like Algorithm to Construct Quasi-Cyclic LDPC Codes,” 2023 12th International Symposium on Topics in Coding (ISTC), Brest, France, pp. 1–5, 2023.

A. Gomez-Fonseca, R. Smarandache, and D. G. M. Mitchell, “On the Tanner Cycle Distribution of QC-LDPC Codes from Polynomial Parity-Check Matrices,” 2023 IEEE International Symposium on Information Theory (ISIT), Taipei, Taiwan, pp. 2356–2361, 2023.

H. Chimal-Dzul and A. Gomez-Fonseca, “Using Partial Orthomorphisms to Construct Short Quasi-Cyclic LDPC Codes with Girth at Least 6,” 2023 12th International Symposium on Topics in Coding (ISTC), Brest, France, pp. 1–5, 2023.

R. Smarandache, A. Gomez-Fonseca, and D. G. M. Mitchell, “Using Minors to Construct Generator Matrices for Quasi-Cyclic LDPC Codes,” 2022 IEEE International Symposium on Information Theory (ISIT), Espoo, Finland, pp. 548–553, 2022.

A. Gomez-Fonseca, R. Smarandache, and D. G. M. Mitchell, “Necessary and Sufficient Girth Conditions for LDPC Tanner Graphs with Denser Protographs,” 2021 11th International Symposium on Topics in Coding (ISTC), Montreal, QC, Canada, pp. 1–5, 2021.

R. Smarandache and D. G. M. Mitchell, “Necessary and Sufficient Girth Conditions for Tanner Graphs of Quasi-Cyclic LDPC Codes,” 2021 IEEE International Symposium on Information Theory (ISIT), Melbourne, Australia, pp. 380–385, 2021.

C. Zhou, D. G. M. Mitchell, and R. Smarandache, “Free Pseudodistance Growth Rates for Spatially Coupled LDPC Codes over the BEC,” 2018 IEEE Information Theory Workshop (ITW), Guangzhou, China, pp. 1–5, 2018.

L. Chen, S. Mo, D. J. Costello, Jr., D. G. M. Mitchell, and R. Smarandache, “A Protograph-Based Design of Quasi-Cyclic Spatially Coupled LDPC Codes,” 2017 IEEE International Symposium on Information Theory (ISIT), Aachen, Germany, pp. 1683–1687, 2017.

R. Smarandache and M. Haenggi, “Bethe and M-Bethe Permanent Inequalities,” 2015 IEEE Global Communications Conference (GLOBECOM), San Diego, CA, USA, pp. 1–6, 2015.

R. Smarandache, “Pseudocodewords from Bethe Permanents,” 2013 IEEE International Symposium on Information Theory (ISIT), Istanbul, Turkey, pp. 2059–2063, 2013.

D. G. M. Mitchell, R. Smarandache, and D. J. Costello, Jr., “Constructing Good QC-LDPC Codes by Pre-lifting Protographs,” 2012 IEEE Information Theory Workshop (ITW), Lausanne, Switzerland, pp. 202–206, 2012.

D. G. M. Mitchell, R. Smarandache, and D. J. Costello, Jr., “Quasi-Cyclic LDPC Codes Based on Pre-Lifted Protographs,” IEEE Information Theory Workshop (ITW), Paraty, Brazil, Oct. 2011.

R. Smarandache, D. G. M. Mitchell, and D. J. Costello, Jr., “Partially Quasi-Cyclic Protograph-Based LDPC Codes,” IEEE International Conference on Communications (ICC), Kyoto, Japan, June 2011.

D. G. M. Mitchell, R. Smarandache, M. Lentmaier, and D. J. Costello, Jr., “Quasi-Cyclic Asymptotically Regular LDPC Codes,” IEEE Information Theory Workshop (ITW), Dublin, Ireland, Aug.–Sept. 2010.

V. Tomas, J. Rosenthal, and R. Smarandache, “Reverse Maximum Distance Profile Convolutional Codes over the Erasure Channel,” 19th International Symposium on Mathematical Theory of Networks and Systems, Budapest, Hungary, July 2010.

R. Smarandache, “On Minimal Pseudo-Codewords,” IEEE International Symposium on Information Theory, Austin, Texas, June 2010.

A. E. Pusane, R. Smarandache, P. O. Vontobel, and D. J. Costello, Jr., “On the Iterative Decoding of LDPC Convolutional Codes,” 18th IEEE Signal Processing and Communications Applications Conference, Diyarbakir, Turkey, Apr. 2010.

A. G. Dimakis, R. Smarandache, and P. O. Vontobel, “Channel Coding LP Decoding and Compressed Sensing LP Decoding: Further Connections,” International Zurich Seminar on Communications, Zurich, Switzerland, Mar. 2010.

R. Smarandache and M. F. Flanagan, “Spectral Graph Analysis of Quasi-Cyclic Codes,” IEEE Global Communications Conference, Honolulu, Hawaii, Dec. 2009.

R. Smarandache and P. O. Vontobel, “Absdet-Pseudo-Codewords and Perm-Pseudo-Codewords: Definitions and Properties,” IEEE International Symposium on Information Theory, Seoul, South Korea, July 2009.

V. Tomas, J. Rosenthal, and R. Smarandache, “Decoding of MDP Convolutional Codes over the Erasure Channel,” IEEE International Symposium on Information Theory, Seoul, South Korea, July 2009.

A. E. Pusane, R. Smarandache, P. O. Vontobel, and D. J. Costello, Jr., “On Deriving Good LDPC Convolutional Codes from QC LDPC Block Codes,” IEEE International Symposium on Information Theory, Nice, France, June 2007.

R. Smarandache, A. Pusane, D. J. Costello, Jr., and P. O. Vontobel, “Pseudo-codewords in LDPC Convolutional Codes,” IEEE International Symposium on Information Theory, Seattle, Washington, July 2006.

P. O. Vontobel and R. Smarandache, “On Minimal Pseudo-Codewords of Tanner Graphs from Projective Planes,” 43rd Allerton Conference on Communications, Control, and Computing, Monticello, Illinois, Oct. 2005.

P. Vontobel, R. Smarandache, N. Kiyavash, J. Teutsch, and D. Vukobratović, “On the Minimal Pseudo-Codewords of Codes from Finite Geometries,” IEEE International Symposium on Information Theory, Adelaide, Australia, Sept. 2005.

R. Smarandache and P. O. Vontobel, “On Regular Quasi-Cyclic LDPC Codes from Binomials,” IEEE International Symposium on Information Theory, Chicago, Illinois, July 2004.

M. Greferath, M. O’Sullivan, and R. Smarandache, “Construction of Good LDPC Codes Using Dilation Matrices,” IEEE International Symposium on Information Theory, Chicago, Illinois, July 2004.

H. Glüsing-Lüerßen, R. Hutchinson, J. Rosenthal, and R. Smarandache, “Convolutional Codes Which Are Maximum Distance Separable and Which Have a Maximum Distance Profile,” 41st Annual Allerton Conference on Communication, Control, and Computing, Monticello, Illinois, Oct. 2003.

M. O’Sullivan and R. Smarandache, “High-Rate, Short Length, (3, 3s)-Regular LDPC Codes of Girth 6 and 8,” IEEE International Symposium on Information Theory, Yokohama, Japan, July 2003.

M. O’Sullivan, M. Greferath, and R. Smarandache, “Construction of LDPC Codes from Affine Permutation Matrices,” 40th Annual Allerton Conference on Communication, Control, and Computing, Monticello, Illinois, Oct. 2002.

M. O’Sullivan, M. Greferath, and R. Smarandache, “Analysis of Iterative Decoding Algorithms,” 15th International Symposium on the Mathematical Theory of Networks and Systems, Notre Dame, Indiana, Aug. 2002.

R. Smarandache, H. Glüsing-Lüerßen, and J. Rosenthal, “Construction and Decoding of Strongly MDS Convolutional Codes,” 15th International Symposium on the Mathematical Theory of Networks and Systems, Notre Dame, Indiana, Aug. 2002.

R. Smarandache, H. Glüsing-Lüerßen, and J. Rosenthal, “Strongly MDS Convolutional Codes with Maximal Decoding Capability,” IEEE International Symposium on Information Theory, Lausanne, Switzerland, July 2002.

R. Smarandache and J. Rosenthal, “Construction Results for MDS-Convolutional Codes,” IEEE International Symposium on Information Theory, Sorrento, Italy, July 2000.

J. Rosenthal and R. Smarandache, “On the Dual of MDS Convolutional Codes,” 36th Annual Allerton Conference on Communication, Control, and Computing, Monticello, Illinois, Oct. 1998.

R. Smarandache and J. Rosenthal, “Convolutional Code Constructions Resulting in Maximal or Near Maximal Free Distance,” IEEE International Symposium on Information Theory, Boston, Massachusetts, July 1998.

R. Smarandache, H. Glüsing-Lüerßen, and J. Rosenthal, “Generalized First Order Descriptions and Canonical Forms for Convolutional Codes,” 13th International Symposium on Mathematical Theory of Networks and Systems, Padova, Italy, July 1998.

R. Smarandache and J. Rosenthal, “A State Space Approach for Constructing MDS Rate 1/n Convolutional Codes,” IEEE Information Theory Workshop, Killarney, Ireland, June 1998.

J. Rosenthal and R. Smarandache, “Construction of Convolutional Codes Using Methods from Linear System Theory,” 35th Annual Allerton Conference on Communication, Control, and Computing, Monticello, Illinois, Oct. 1997.