{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T00:41:11Z","timestamp":1774312871152,"version":"3.50.1"},"reference-count":69,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,5,22]],"date-time":"2021-05-22T00:00:00Z","timestamp":1621641600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007161","name":"Secretar\u00eda de Investigaci\u00f3n y Posgrado, Instituto Polit\u00e9cnico Nacional","doi-asserted-by":"publisher","award":["SIP-20210345"],"award-info":[{"award-number":["SIP-20210345"]}],"id":[{"id":"10.13039\/501100007161","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In this paper, the parameter-switching technique was applied to control chaos in the Chen oscillator and as a decryption mechanism in a secure transmission system, to transmit RGB and grayscale images. In the past few decades, considerable efforts have been put into the study of the stabilization of chaotic dynamical systems. Most of the well-known chaos control methods, such as Ott, Grebogi, and Yorke (OGY), Pyragas, and open-loop methods, force an unstable periodic orbit into a stable one while distorting the original attractor. On the other hand, the parameter-switching technique is an elegant method that can synthesize an already-existing stable orbit, thereby preserving the underlying attractor. Consequently, the main contributions of this work were the FPGA realizations of the parameter-switching method and a secure image transmission system using a synchronized master and slave topology. The results of the parameter-switching technique and synchronization were verified using phase plots and time series. The chaos-encrypted image from the image transmission system, verified using correlation, showed no relativity with the original image, while the recovery of the decrypted image has no loss of quality. The encryption and decryption system was symmetric, whereby the key was private. In this work, co-simulations were performed in Active-HDL with MATLAB\/Simulink, while the target FPGA board was the Xilinx\u2019s Artix-7 AC701.<\/jats:p>","DOI":"10.3390\/sym13060923","type":"journal-article","created":{"date-parts":[[2021,5,24]],"date-time":"2021-05-24T02:32:43Z","timestamp":1621823563000},"page":"923","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["FPGA Realization of the Parameter-Switching Method in the Chen Oscillator and Application in Image Transmission"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1897-5992","authenticated-orcid":false,"given":"Vincent-Ademola","family":"Adeyemi","sequence":"first","affiliation":[{"name":"Instituto Polit\u00e9cnico Nacional, IPN-CITEDI, Tijuana 22435, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8912-8822","authenticated-orcid":false,"given":"Jose-Cruz","family":"Nu\u00f1ez-Perez","sequence":"additional","affiliation":[{"name":"Instituto Polit\u00e9cnico Nacional, IPN-CITEDI, Tijuana 22435, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9258-6595","authenticated-orcid":false,"given":"Yuma","family":"Sandoval Ibarra","sequence":"additional","affiliation":[{"name":"Departamento de Posgrado, Universidad Polit\u00e9cnica de L\u00e1zaro C\u00e1rdenas (UPLC), L\u00e1zaro C\u00e1rdenas 60950, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6116-6464","authenticated-orcid":false,"given":"Francisco-Javier","family":"Perez-Pinal","sequence":"additional","affiliation":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico, Instituto Tecnol\u00f3gico de Celaya, Celaya 38010, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7187-4686","authenticated-orcid":false,"given":"Esteban","family":"Tlelo-Cuautle","sequence":"additional","affiliation":[{"name":"Instituto Nacional de Astrof\u00edsica, \u00d3ptica y Electr\u00f3nica, INAOE, San Andres Cholula 72840, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Peletier, M.A., van Santen, R.A., and Steur, E. (2019). Chapter 1\u2014The many facets of complexity. Complexity Science: An Introduction, World Scientific Publishing Co.","DOI":"10.1142\/10973"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1485759","DOI":"10.1155\/2016\/1485759","article-title":"A new method to solve numeric solution of nonlinear dynamic system","volume":"2016","author":"Hu","year":"2016","journal-title":"Math. Probl. Eng."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1529","DOI":"10.1007\/s10483-018-2383-6","article-title":"Clean numerical simulation: A new strategy to obtain reliable solutions of chaotic dynamics","volume":"39","author":"Li","year":"2018","journal-title":"Appl. Math. Mech. Engl. Ed."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1550187","DOI":"10.1142\/S0218127415501874","article-title":"A new reliable numerical method for computing chaotic solutions of dynamical systems: The Chen attractor case","volume":"25","author":"Lozi","year":"2015","journal-title":"Int. J. Bifurc. Chaos"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1747","DOI":"10.1007\/s11071-018-4657-4","article-title":"First integrals and analytical solutions of some dynamical systems","volume":"95","author":"Haq","year":"2019","journal-title":"Nonlinear Dyn."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Mellodge, P. (2016). Chapter 4\u2014Characteristics of Nonlinear Systems. A Practical Approach to Dynamical Systems for Engineers, Woodhead Publishing.","DOI":"10.1016\/B978-0-08-100202-5.00004-8"},{"key":"ref_7","unstructured":"Ling, W.K. (2010). Nonlinear Digital Filters: Analysis and Applications, Academic Press."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"105588","DOI":"10.1016\/j.cnsns.2020.105588","article-title":"A test for fractal boundaries based on the basin entropy","volume":"95","author":"Puy","year":"2021","journal-title":"Commun. Nonlinear Sci. Numer. Simul."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"105709","DOI":"10.1016\/j.cnsns.2021.105709","article-title":"A new auto-replication in systems of attractors with two and three merged basins of attraction via control","volume":"96","author":"Goufo","year":"2021","journal-title":"Commun. Nonlinear Sci. Numer. Simul."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"132779","DOI":"10.1016\/j.physd.2020.132779","article-title":"Statistical basin of attraction in time-delayed cutting dynamics: Modelling and computation","volume":"416","author":"Yan","year":"2021","journal-title":"Phys. D Nonlinear Phenom."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Lee, M.Y., and Kim, Y.I. (2020). Development of a Family of Jarratt-Like Sixth-Order Iterative Methods for Solving Nonlinear Systems with their basins of attraction. Algorithms, 13.","DOI":"10.3390\/a13110303"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"033502","DOI":"10.1063\/5.0007446","article-title":"Functionalization of electrostatic nonlinearities to overcome mode aliasing limitations in the sensitivity of mass microsensors based on energy localization editors-pick","volume":"117","author":"Rabenimananaa","year":"2020","journal-title":"Appl. Phys. Lett."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"e2003826","DOI":"10.1002\/adma.202003826","article-title":"Scalable functionalization of optical fibers using atomically thin semiconductors","volume":"32","author":"Ngo","year":"2020","journal-title":"Adv. Mater."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"7469","DOI":"10.1007\/s00500-019-04373-w","article-title":"An exponential jerk system, its fractional-order form with dynamical analysis and engineering application","volume":"24","author":"Rajagopal","year":"2020","journal-title":"Soft Comput."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"138745","DOI":"10.1016\/j.msea.2019.138745","article-title":"Separation of dynamic recrystallization parameter domains from a chaotic system for Ti\u20136Al\u20134V alloy and its application in parameter loading path design","volume":"772","author":"Quan","year":"2020","journal-title":"Mater. Sci. Eng. A"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1750215","DOI":"10.1142\/S0218127417502157","article-title":"Chaotic Traversal (CHAT): Very Large Graphs Traversal Using Chaotic Dynamics","volume":"27","author":"Changaival","year":"2017","journal-title":"Int. J. Bifurc. Chaos"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1007\/s10916-016-0586-2","article-title":"A Secure Dynamic Identity and Chaotic Maps Based User Authentication and Key Agreement Scheme for e-Healthcare Systems","volume":"40","author":"Li","year":"2016","journal-title":"J. Med. Syst."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Zang, X., Iqbal, S., Zhu, Y., Liu, X., and Zhao, J. (2016). Applications of Chaotic Dynamics in Robotics. Int. J. Adv. Robot. Syst., 13.","DOI":"10.5772\/62796"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5491","DOI":"10.1016\/j.ijleo.2016.02.066","article-title":"A new four-scroll chaotic attractor and its engineering applications","volume":"127","author":"Akgul","year":"2016","journal-title":"Optik"},{"key":"ref_20","unstructured":"Ott, E. (1993). Chaos in Dynamical Systems, Cambridge University Press."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"778","DOI":"10.1007\/s40435-017-0341-7","article-title":"Qualitative analysis and chaos control in a density-dependent host-parasitoid system","volume":"6","author":"Din","year":"2018","journal-title":"Int. J. Dyn. Control"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1550096","DOI":"10.1142\/S0218127415500960","article-title":"Control of multichaotic systems using the extended OGY method","volume":"25","author":"Nobakhti","year":"2015","journal-title":"Int. J. Bifurc. Chaos"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1515\/ijnsns-2017-0077","article-title":"Bifurcation analysis and chaos control in a second order rational difference equation","volume":"19","author":"Din","year":"2018","journal-title":"Int. J. Nonlinear Sci. Numer. Simul."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1016\/j.sysconle.2014.04.001","article-title":"Pyragas stabilizability via delayed feedback with periodic control gain","volume":"69","author":"Leonov","year":"2014","journal-title":"Syst. Control Lett."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1007\/s10665-014-9730-5","article-title":"On the chaos control of the Qi system","volume":"90","author":"Xu","year":"2015","journal-title":"J. Eng. Math."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2897","DOI":"10.1007\/s11538-018-0492-5","article-title":"Control of Pyragas applied to a coupled system with unstable periodic orbits","volume":"80","author":"Amster","year":"2018","journal-title":"Bull. Math. Biol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"026213","DOI":"10.1103\/PhysRevE.66.026213","article-title":"Open-loop sustained chaos and control: A manifold approach","volume":"66","author":"Schwartz","year":"2002","journal-title":"Phys. Rev. E"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1550065","DOI":"10.1142\/S0218126615500656","article-title":"Feed-forward slope compensated PFC for chaos control","volume":"25","author":"Li","year":"2015","journal-title":"J. Circuits Syst. Comput."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"043106","DOI":"10.1063\/1.4946811","article-title":"Chaos control of Hastings-Powell model by combining chaotic motions","volume":"26","author":"Danca","year":"2016","journal-title":"Chaos"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"702","DOI":"10.1016\/j.camwa.2013.01.028","article-title":"Sustaining stable dynamics of a fractional-order chaotic financial system by parameter switching","volume":"66","author":"Danca","year":"2013","journal-title":"Comput. Math. Appl."},{"key":"ref_31","first-page":"101","article-title":"Parameter switching in a generalized Duffing system: Finding the stable attractors","volume":"223","author":"Danca","year":"2013","journal-title":"Appl. Math. Comput."},{"key":"ref_32","first-page":"5532106","article-title":"FPGA Realization of Spherical Chaotic System with Application in Image Transmission","volume":"2021","author":"Adeyemi","year":"2021","journal-title":"Math. Probl. Eng."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1016\/j.micpro.2019.02.012","article-title":"High speed FPGA-based chaotic oscillator design","volume":"66","author":"Tuna","year":"2019","journal-title":"Microprocess. Microsystem."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"2444","DOI":"10.1002\/cta.2572","article-title":"Secure color image encryption algorithm based on chaotic signals and its FPGA realization","volume":"46","author":"Yang","year":"2018","journal-title":"Int. J. Circuit Theory Appl."},{"key":"ref_35","first-page":"365","article-title":"A novel high speed artifical neural network-based chaotic true random number generator on field programmable gate array","volume":"47","author":"Koyuncu","year":"2018","journal-title":"Int. J. Circuit Theory Appl."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1002\/cta.553","article-title":"FPGA implementation of a coupled-map-lattice-based cryptosystem","volume":"38","author":"Li","year":"2010","journal-title":"Int. J. Circuit Theory Appl."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1129","DOI":"10.1007\/s11071-017-3505-2","article-title":"Quintas-Valles, A.J. Dynamics, FPGA realization and application of a chaotic system with an infinite number of equilibrium points","volume":"89","author":"Volos","year":"2017","journal-title":"Nonlinear Dyn."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"4047957","DOI":"10.1155\/2019\/4047957","article-title":"Analysis and FPGA realization of a novel 5D hyperchaotic four-wing memristive system, active control synchronization, and secure communication application","volume":"2019","author":"Yu","year":"2019","journal-title":"Complexity"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"e4211","DOI":"10.1002\/dac.4211","article-title":"An efficient and lightweight multi-scroll chaos-based hardware solution for protecting fingerprint biometric templates","volume":"33","author":"Azzaz","year":"2019","journal-title":"Int. J. Commun. Syst."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"23203","DOI":"10.1007\/s11042-019-08517-w","article-title":"Low power and high-speed FPGA implementation for 4D memristor chaotic system for image encryption","volume":"79","author":"Hagras","year":"2020","journal-title":"Multimed. Tools Appl."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Guill\u00e9n-Fern\u00e1ndez, O., Mel\u00e9ndez-Cano, A., Tlelo-Cuautle, E., N\u00fa\u00f1ez-P\u00e9rez, J.C., and Rangel-Magdaleno, J.J. (2019). On the synchronization techniques of chaotic oscillators and their FPGA-based implementation for secure image transmission. PLoS ONE, 14.","DOI":"10.1371\/journal.pone.0209618"},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Tlelo-Cuautle, E., D\u00edaz-Mu\u00f1oz, J.D., Gonz\u00e1lez-Zapata, A.M., Li, R., Le\u00f3n-Salas, W.D., Fern\u00e1ndez, F.V., Guill\u00e9n-Fern\u00e1ndez, O., and Cruz-Vega, I. (2020). Chaotic Image Encryption Using Hopfield and Hindmarsh\u2013Rose Neurons Implemented on FPGA. Sensors, 20.","DOI":"10.3390\/s20051326"},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Tlelo-Cuautle, E., Pano-Azucena, A.D., Guill\u00e9n-Fern\u00e1ndez, O., and Silva-Ju\u00e1rez, A. (2019). Synchronization and Applications of Fractional-Order Chaotic Systems. Analog\/Digital Implementation of Fractional Order Chaotic Circuits and Applications, Springer.","DOI":"10.1007\/978-3-030-31250-3"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"13841","DOI":"10.1007\/s11042-019-08592-z","article-title":"FPGA based generic RO TRNG architecture for image confusion","volume":"79","author":"Sivaraman","year":"2020","journal-title":"Multimed. Tools Appl."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"6675565","DOI":"10.1155\/2021\/6675565","article-title":"A Novel Hyperchaotic Image Encryption System Based on Particle Swarm Optimization Algorithm and Cellular Automata","volume":"2021","author":"Zeng","year":"2021","journal-title":"Secur. Commun. Netw."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"110102","DOI":"10.1016\/j.chaos.2020.110102","article-title":"A new one-dimensional chaotic system with applications in image encryption","volume":"139","author":"Wang","year":"2020","journal-title":"Chaos Solitons Fractals"},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Li, Z., Peng, C., Tan, W., and Li, L. (2021). An Efficient Plaintext-Related Chaotic Image Encryption Scheme Based on Compressive Sensing. Sensors, 21.","DOI":"10.3390\/s21030758"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"14284","DOI":"10.1109\/ACCESS.2021.3052161","article-title":"New DNA Coded Fuzzy Based (DNAFZ) S-Boxes: Application to Robust Image Encryption Using Hyper Chaotic Maps","volume":"9","author":"Mohamed","year":"2021","journal-title":"IEEE Access"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"386","DOI":"10.1007\/s40435-019-00573-2","article-title":"Mathematical and numerical analysis of the dynamical behavior of Chen oscillator","volume":"8","author":"Adeyemi","year":"2020","journal-title":"Int. J. Dyn. Control"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"1850018","DOI":"10.1142\/S0218127418500189","article-title":"On the Lorenz and Chen Systems","volume":"28","author":"Barboza","year":"2018","journal-title":"Int. J. Bifurc. Chaos"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"1465","DOI":"10.1142\/S0218127499001024","article-title":"Yet another chaotic attractor","volume":"9","author":"Chen","year":"1999","journal-title":"Int. J. Bifurc. Chaos"},{"key":"ref_52","first-page":"1","article-title":"Generating Lorenz-like and Chen-like attractors from a simple algebraic structure","volume":"57","author":"Wang","year":"2014","journal-title":"Sci. China Inf. Sci."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"439","DOI":"10.1515\/ms-2015-0148","article-title":"Note on a parameter-switching method for nonlinear ODEs","volume":"66","author":"Danca","year":"2016","journal-title":"Math. Slovaca"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"1650096","DOI":"10.1142\/S0218127416500966","article-title":"Emulating \u201cChaos + Chaos = Order\u201d in Chen\u2019s circuit of fractional order by parameter switching","volume":"26","author":"Tang","year":"2016","journal-title":"Int. J. Bifurc. Chaos"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1016\/j.cnsns.2012.08.019","article-title":"Convergence of a parameter switching algorithm for a class of nonlinear continuous systems and a generalization of Parrondo\u2019s paradox","volume":"18","author":"Danca","year":"2013","journal-title":"Commun. Nonlinear Sci. Numer. Simul."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"1381","DOI":"10.1142\/S0218127401002778","article-title":"Synchronization of chaotic systems: A generalized Hamiltonian systems approach","volume":"11","year":"2001","journal-title":"Int. J. Bifurc. Chaos"},{"key":"ref_57","first-page":"415","article-title":"Application of generalized Hamiltonian systems to chaotic synchronization","volume":"9","author":"Pei","year":"2009","journal-title":"Nonlinear Dyn. Syst. Theory"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"010505","DOI":"10.1088\/1674-1056\/25\/1\/010505","article-title":"Parrondo\u2019s paradox for chaos control and anticontrol of fractional-order systems","volume":"25","author":"Danca","year":"2016","journal-title":"Chin. Phys. B"},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"R71","DOI":"10.1142\/S0219477502000701","article-title":"A review of Parrondo\u2019s paradox","volume":"2","author":"Harmer","year":"2002","journal-title":"Fluct. Noise Lett."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"101543","DOI":"10.1016\/j.newast.2020.101543","article-title":"Fractal basins of attraction in a binary quasar model","volume":"84","author":"Kumar","year":"2021","journal-title":"New Astron."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"887","DOI":"10.1002\/asna.202013822","article-title":"Convergence properties of equilibria in the restricted three-body problem with prolate primaries","volume":"341","author":"Saeed","year":"2020","journal-title":"Astron. Nachrichten"},{"key":"ref_62","first-page":"7470204","article-title":"A fast enhanced secure image chaotic cryptosystem based on hybrid chaotic magic transform","volume":"2017","author":"Koppu","year":"2017","journal-title":"Model. Simul. Eng."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1016\/j.aeue.2018.03.007","article-title":"A novel digital programmable multi-scroll chaotic system and its application in FPGA-based audio secure communication","volume":"88","author":"Chang","year":"2018","journal-title":"AEU Int. J. Electron. Commun."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"1879","DOI":"10.1007\/s11071-015-2284-x","article-title":"FPGA realization of a chaotic communication system applied to image processing","volume":"82","year":"2015","journal-title":"Nonlinear Dyn."},{"key":"ref_65","doi-asserted-by":"crossref","unstructured":"Sadoudi, S., Tanougast, C., Azzaz, M.S., and Dandache, A. (2013). Design and FPGA implementation of a wireless hyperchaotic communication system for secure real-time image transmission. EURASIP J. Image Video Process., 43.","DOI":"10.1186\/1687-5281-2013-43"},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"1838","DOI":"10.1109\/TMTT.2020.3041249","article-title":"An OOK chirp spread spectrum backscatter communication system for wireless power transfer applications","volume":"69","author":"Belo","year":"2021","journal-title":"IEEE Trans. Microw. Theory Tech."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"881","DOI":"10.1109\/JSYST.2020.2991078","article-title":"Modulation parameter estimation of LFM interference for direct sequence spread spectrum communication system in Alpha-Stable noise","volume":"15","author":"Liu","year":"2021","journal-title":"IEEE Syst. J."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"103740","DOI":"10.1016\/j.micpro.2020.103740","article-title":"Reliable advanced encryption standard hardware implementation: 32-bit and 64-bit data-paths","volume":"81","author":"Sheikhpour","year":"2021","journal-title":"Microprocess. Microsystem."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"012022","DOI":"10.1088\/1742-6596\/1755\/1\/012022","article-title":"Data Security Implementation using Data Encryption Standard Method for Student Values at the Faculty of Medicine, University of North Sumatra","volume":"1755","author":"Ikhwan","year":"2021","journal-title":"J. Phys. Conf. Ser."}],"container-title":["Symmetry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-8994\/13\/6\/923\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:05:53Z","timestamp":1760162753000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-8994\/13\/6\/923"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,5,22]]},"references-count":69,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2021,6]]}},"alternative-id":["sym13060923"],"URL":"https:\/\/doi.org\/10.3390\/sym13060923","relation":{},"ISSN":["2073-8994"],"issn-type":[{"value":"2073-8994","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,5,22]]}}}