Short Bio

Diego Napp received a Ph.D. degree in Mathematics from the University of Groningen, the Netherlands in 2008. He was a postdoctoral researcher at University of Aveiro, Portugal, from 2008 to 2011. Between 2011 and 2013, he stayed at the Universities of Valladolid and Jaume I, Spain, supported by a Spanish Research contract Juan de la Cierva. From 2014 to 2018 he enjoyed an FCT Research grant at the University of Aveiro. In 2018 he moved to the Department of Mathematics, University of Alicante (Spain) and became full Professor in 2024. His research interests are in the areas of algebraic coding theory and code-based cryptography.  

Research Interests

• Algebraic Coding Theory

• Code-based Cryptography

• Systems Theory

• Convolutional Codes

• Polynomial Matrices and Matrices over Finite fields

PhD Students

• • • Marisa Lapa Toste, Title: Distance properties of convolutional codes over Z_p^r, (with Prof. Raquel Pinto)  Sept. 2016  (“Cum laude”). 

    • Maria da Conceiçao Santos Rocha, Title: Convolutional encoders over Z_p^r (with Prof. Raquel Pinto), 22 Nov.  2019. 

    • Filipa Vanessa de Sousa Santana, Title: Convolutional codes for multi-shot network coding (with Prof. Raquel Pinto) 21 Jan. 2022. 

    • Cláudia Ferreira Sebastiao, Title: Smaller keys for McEliece cryptosystems using convolutional encoders (with Prof. Paulo Almeida) 21 Jan. 2022. 

    • Miguel Beltra Vidal, Title: Variants of the McEliece cryptosystem, (with Prof. Paulo Almeida) 11 June 2025.

Master Students

• • • Jorge Brandao, Title: Quantum computation and cryptography, 27/07/2018, Mark: 19 out of 20 (with Prof. P. Almeida and Prof. M. Falcao)

Editorial board

• • • Associate editor:  IEEE transactions on information theory

Books

• • • Criptografia e segurança (in Portuguese), with Prof. P. Almeida, 2017, Publindústria, ISBN 9897232109. 

Articles (read them in ResearchGate)

In Coding Theory 

1. On the existence of non-catastrophic p -encoders of (2,1) convolutional codes over Zp2, with R. Pinto and C. Rocha, in Journal of Algebra and Its Applications, https://doi.org/10.1142/S0219498825500690 , 2023.

2. Weighted Reed-Solomon convolutional codes, with Alfarano, Gianira ;Neri, Alessandro ;Requena, Veronica in Linear and Multilinear algebra, DOI: 10.1080/03081087.2023.2169232 , 2023.

3. State representations of convolutional codes over a finite ring, with R. Pinto and C. Rocha in Linear Algebra and its Applications, vol. 640, Pages 48-66, 2022. 

4. Weight-2 input sequences of 1/n convolutional codes from linear systems point of view, with M.V. Herranz and C. Perea in AIMS Mathematics, Vol 8 - 1, pp. 713 - 732, 2023.

5. State Realizations of Periodic Convolutional Codes, with E. Fornasini, R. Pereira, P. Pinto and P. Rocha, in SIAM Journal on Control and Optimization, 60 - 5, pp. 2927 - 2946. SIAM, 2022.

6. Noncatastrophic convolutional codes over a finite ring, with R. Pinto and C. Rocha, in Journal of Algebra and Its Applications,  https://doi.org/10.1142/S0219498823500299  2023

7. List decoding of Convolutional Codes over integer residue rings, with J. Lieb, and R. Pinto, in Finite Fields and their Applications, Vol. 72, 2021. https://doi.org/10.1016/j.ffa.2021.101815 

8.  State Realizations of 2-Periodic Convolutional Codes: a switching system approach, with E. Fornasini, R. Pereira, P. Pinto and P.Rocha, in IFAC-PapersOnLine, vol 54, Issue 9, Pages 114-118, 2021.

9. A matrix based list decoding algorithm for linear codes over integer residue rings with R Pinto, E Saçıkara and M Toste Linear Algebra and its Applications, Volume 614, Pages 376-393, 2021.

10. A new rank metric for convolutional codes, with  P Almeida, Designs, Codes and Cryptography, vol. 89, pages 53–73, 2021.

11. Minimal State-Space Representation of Convolutional Product Codes, with J.J. Climent, R. Pinto and V. Requena, Mathematics. 9 - 12, pp. 1 - 21. MDPI, 2021.

12. Generalized Column Distances, with S. Cardell and M. Firer, IEEE Transactions on Information Theory,   https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9110618   2020, IF: 3.215.

13. 1/n Turbo Codes from linear system point of view , with  V. Herranz and C. Perea, in Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas. Springer, https://doi.org/10.1007/s13398-020-00850-2  2020. IF: 1.028.

14. Systematic Maximum Sum Rank Codes, with P. Almeida and U. Martinez-Peñas, in Finite Fields and their Applications, vol 65, 2020, https://doi.org/10.1016/j.ffa.2020.101677,  IF: 1.254.

15. Locally Repairable Convolutional Codes with Sliding Window Repair, with Umberto Martínez-Peñas, IEEE Transactions on Information Theory, vol. 66 (8), 2020, https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9020074  IF: 3.215.

16.  Block Toeplitz matrices for burst-correcting convolutional codes, Climent, J.-J.; Napp, D. and Requena, V.  Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas. Springer, vol. 114 (38), 2020. IF: 1.028.

17.  Column Distances of Convolutional Codes Over Z p r , Napp, D.; Pinto, R. and Toste, M. IEEE Transactions on Information theory vol. 65 (2) P. 1063-1071, 2019, IF: 3.215.

18.  Serial concatenation of a block code and a 2D convolutional code, Herranz, V.; Napp, D. and Perea, C. Multidimensional systems and signal processing vol. 30 (3) P. 1113-1127 , 2019, IF: 2.338.

19.  On duals and parity-checks of convolutional codes over Z p r , El Oued, M.; Napp, D.; Pinto, R. and Toste, M. Finite Fields and their Applications vol. 55 P. 1-20, 2019. IF: 1.254.

20.  Realization of 2D (2,2)-periodic encoders by means of 2D periodic separable Roesser models, Ricardo Pereira, Diego Napp ; Raquel Pinto and Paula Rocha Journal of Applied Mathematics and Computer Science, 19 - 3, p. 527 - 539, 2019. IF:1.504.

21.  Periodic state-space representations of periodic convolutional codes, Napp, D.; Pereira, R.; Pinto, R. and Rocha, P. Cryptography and communications-discrete-structures boolean functions and sequences Volume: 11 (4) P. 585-595, 2019. IF: 1.099.

22. Concatenation of convolutional codes and rank metric codes for multi-shot network coding, Napp, D.; Pinto, R. and Sidorenko, V. Designs Codes and Cryptography Volume: 86 (2) p. 303-318, 2018, IF: 1,224.

23.  MDS 2D convolutional codes with optimal 1D horizontal projections, Almeida, P.; Napp, D. and Pinto, R. Designs Codes and Cryptography Volume: 86 (2) p.285- 302, 2018, IF: 1,224.

24.  Series concatenation of 2D convolutional codes by means of input-state-output representations, Climent, J.-J.; Napp, D.; Pinto, R. and Simoes, R. International Journal of Control Volume: 91 (12) P. 2682-2691, 2018. IF: 2.93.

25.  A State Space Approach to Periodic Convolutional Codes, Napp, D.; Pereira, R. and Rocha, P. Lecture Notes in Computer Science Volume: 10495 P. 238-247, 2017, IF: 0.402.

26.  On MDS convolutional codes over Z p r , Napp, D.; Pinto, R. and Toste, M. Designs Codes and Cryptography Volume: 83 (1) P. 101-114, 2017, IF: 1,224.

27.  Column Rank Distances of Rank Metric Convolutional Codes, Napp, D.; Pinto, R.; Rosenthal, J. and Vettori, P. Lecture Notes in Computer Science Volume: 10495 P. 248-256, 2017, IF: 0.402.

28.  Construting strongly- MDS convolutional codes with maximum distance profile, Napp, D. and Smarandache, R. Adv. in Mathematics of Communications Volume: 10 (2) P. 275-290, 2016, IF: 0.879.

29.  Decoding of 2D convolutional codes over the erasure channel, Climent, J.-J.; Napp, D.; Pinto, R. and Simoes, R. Adv. in Mathematics of Communications Volume: 10 (1) p. 179-193. 2016, IF: 0.879.

30.  Maximum Distance Separable 2D Convolutional Codes, Climent, J.-J.; Napp, D. and Perea, C.; Pinto, R.  IEEE Trans. on Information theory Volume: 62 (2) p. 669-680, 2016, IF: 3.215.

31. Input-state-Output representations and constructions of Finite Support 2D convolutional codes, Napp, D.; Perea, C. and Pinto, R. Adv. in Mathematics of Communications Volume: 4 (4) P. 533-545, 2010, IF: 0.879.

In Algebra and Matrices 

1.  Superregular matrices and applications to convolutional codes, Almeida, P. J.; Napp, D. and Pinto, R. Linear Algebra and its Applications Volume: 499 P. 1-25, 2016, IF: 0,977.

2.  A new class of superregular matrices and MDP convolutional codes, Almeida, P.; Napp, D. and Pinto, R. Linear Algebra and its Applications Volume: 439 (7), P. 2145-2157, 2013, IF: 0,977.

3.  A construction of MDS 2D convolutional codes of rate 1/n based on superregular matrices, Climent, J.-J.; Napp, D.; Perea, C. and Pinto, R. Linear Algebra and its Applications Volume: 437 (3) P. 766-780, 2012, IF: 0,977.

4.  Linear-quadratic control and quadratic differential forms for multidimensional behaviors, Napp, D. and Trentelman, H. L. Linear Algebra and its Applications Volume: 434 (1) P. 117-130, 2011, IF: 0,977.

5. Periodic Behaviors, Napp, D.; van der Put, M. and Shankar, S. SIAM Journal of Control and Optimization Volume: 48 (7) P. 4652-4663, 2010, IF: 1.986. 

6. Almost direct sum decomposition and implementation of 2D behaviors, Napp, D. Mathematics of Control, Signals and Systems, Volume 21 (1), p. 1-19, 2009, IF: 0.8.

7. Algorithms for multidimensional spectral factorization and sum of squares, Diego Napp and H.L. Trentelman. Linear Algebra and its Applications, 429, 2008, p.1114-1134, IF: 0,977.

In Systems Theory

1. Discrete-Time Positive Periodic Systems With State and Control Constraints, Ait Rami, M. and Napp, D. IEEE Trans. Automatic control Volume: 61 (1) P. 234-239, 2016, IF: 5.093.

2.  Positivity of discrete singular systems and their stability: An LP-based approach, Ait Rami, M. and Napp, D. AUTOMATICA Volume: 50 (1) P. 84-91, 2014, IF: 6.355. 

3.  Time-relevant stability of 2D systems, Napp, D.; Rapisarda, P. and Rocha, P. AUTOMATICA Volume: 47 (11) P. 2373-2382, 2012, IF: 6.355. 

4.  Characterization and Stability of Autonomous Positive Descriptor Systems, Ait Rami, M. and Napp, D. IEEE Trans. Automatic control Volume: 57 (10) P. 2668-2673, 2012, IF: 5.093.

5.  Lyapunov stability of 2D finite-dimensional behaviours, Napp Avelli, D.; Rapisarda, P. and Rocha, P. International Journal of Control Volume: 84 (4) P. 737-745 P. 2011, IF: 2.93

6.  Stabilization of discrete 2D behaviors by regular partial interconnection, Napp, D. and Rocha, P. Mathematics of Control, Signals and Systems Volume: 22 (4) P. 295-316, 2011, IF: 0.8.

7.  Autonomous multidimensional systems and their implementation by behavioral control, Napp Avelli, D. and Rocha, P. Systems and control letters Volume: 59 (3-4) p. 203-208, 2010 IF: 2.624.

8.  Strongly Autonomous Interconnections and Stabilization of 2D, Napp, D. and Rocha, P. Asian Journal of Control, Volume: 12 (2) P. 127-135, 2010, IF 2.005.

9. Implementation of 2D Strongly Autonomous Behaviors by Full and Partial Interconnections, Napp Avelli, D. and Rocha, P. Lecture Notes in Control and Information Sciences Volume: 389 p. 369-379, 2009, IF: 0,269.

10.  Regular implementation in the space of compactly supported functions, Napp, D.; Shankar S. and Trentelman, H.L. Systems and control letters, Volume 57, P.851- 855, 2008, IF: 2.624.

11.  On regular implementability of nD behaviors, Trentelman , H.L. and Napp, D. Systems and control letters, Volume 56, (4), p. 265–271, 2007, IF: 2.624.