Electronic Simulation and Hardware Implementation of Two Coupled Periodically Forced Duffing and Van der Pol oscillators and its Application to Secure Communication

Confirmation of the existence of complex behavior and synchronization of non-identical chaotic systems as reported in literature attracts much interest in secure communication, but practical implementation is still challenging. In this work, the dynamics of coupled non-identical circuits comprising periodically forced Duffing and Van der Pol oscillators is investigated via electronic simulation using Multism software and hardware implementation on electronic circuits board. After complete synchronization is achieved between the Duffing (Transmitter) and Van der Pol (receiver) circuits through the variation of the coupling resistor of the controller, its application to secure communication is therefore demonstrated experimentally and via multism. The results from the electronic simulation and hardware implementation on bread board using analog components are in good agreement with the numerical results in literature

Experimental Wireless Communication Using Chaotic Baseband Waveform

This work was supported by NSFC under Grants 61401354, 61172070, and 61502385, in part by the Key Basic Research Fund of Shaanxi Province under Grant 2016ZDJC0067, in part by the Natural Science Basic Research Plan in Shaanxi Province of China under Grant 2016JQ6015, in part by the Scientific and Technological Innovation Leading Talents Program of Shaanxi Province, and in part by the Foundation of Shaanxi Educational Committee under Grant 17JS086.Peer reviewedPostprin

Symmetric encryption relying on chaotic henon system for secure hardware-friendly wireless communication of implantable medical systems

Healthcare remote devices are recognized as a promising technology for treating health related issues. Among them are the wireless Implantable Medical Devices (IMDs): These electronic devices are manufactured to treat, monitor, support or replace defected vital organs while being implanted in the human body. Thus, they play a critical role in healing and even saving lives. Current IMDs research trends concentrate on their medical reliability. However, deploying wireless technology in such applications without considering security measures may offer adversaries an easy way to compromise them. With the aim to secure these devices, we explore a new scheme that creates symmetric encryption keys to encrypt the wireless communication portion. We will rely on chaotic systems to obtain a synchronized Pseudo-Random key. The latter will be generated separately in the system in such a way that avoids a wireless key exchange, thus protecting patients from the key theft. Once the key is defined, a simple encryption system that we propose in this paper will be used. We analyze the performance of this system from a cryptographic point of view to ensure that it offers a better safety and protection for patients. 2018 by the authors.Acknowledgments: This publication was made possible by NPRP grant #8-408-2-172 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors.Scopu

Kaotik simulasyon labaratuvarı uygulaması

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Kaotik Simulasyon Laboratuvarı tez çalışmasında ,Mühendislik problemlerin çözümünde bugüne kadar kullanılana gelen kaotik yaklaşım modellerini sayısal ortam aracılığıyla daha etkin ve gözlemlenebilir bir araç olarak kullanılması amaçlanmıştır.Kaotik Simulasyon Laboratuvarı Uygulamasında, Kaos Teorisi ile ilgili tanımlamalar, Kaotik Analiz Metodları, Kaotik Bileşenler, Kaos Teorisi hakkındaki yayınlanan kitaplar ve makaleler, Kaotik Denklem Modelleri ve Kaotik Uygulama örnekleri yer almaktadır. Kaotik Simulasyon Laboratuvarı Uygulamasında bulunan gerek görsel içerik, gerekse de yazılı zengin içeriklerle Kaos Teorisini ve mühendislik alanlarındaki uygulamalarının etkin olarak tanıtılması amaçlanmıştır.Belirli başlangıç koşulları altında Chua, Vanderpol, Rossler,Lorenz,Duffing, ve Colpitts gibi Kaos Yöntemleri ile MATLAB Ortamında yapılan Simulasyonların Eksenel Çıkış Diyagramları alınarak uygulamaya zengin görsel içerik kazandırılmıştır.Bundan başka Simulasyon Uygulamasında ,arka planda MATLAB Hesaplama Motoru kabiliyetleri kullanılarak, bir mühendislik problemine MATLAB Hesaplama Motoruna ,Simulasyon Aracı üzerinden ilgili Kaotik Analiz Yöntemi Denklem Takımlarına gerçek zamanlı parameter geçilerek kaotik hesaplama sonuçlarını hem grafiksel hem sayısal büyüklüklerle gösterme ve bu sonuçları analiz etme imkanı vardır.Anahtar Kelimeler: Kaotik Simulasyon Laboratuvarı, Sayısal Ortam, MATLAB Hesaplama Motoru, Kaos YöntemleriIn this thesis, It is aimed to use Chaotic Model Approaches for solving engineering problems by using digital medium tools, more efficiently and observably.In Chaotic Simulation Labratory Application, it is embodied with Definitions of Chaos Theory, Chaotic Analysis Methods, Chaos Theory Components,publised books and essays, Chaotic Equation Models, Chaotic Application Samples.Both visual contents and rich writtens ,it is targeted accomplishing a coprehensive training method in Chaos Theory and its application fields. Under certain initial conditions, Chua,Vanderpol,Rossler,Lorenz,Duffing, and Colpitts Methods are analyzed in MATLAB Medium. Figurative results are included in Application.Furthermore,using efficient aptitude of MATLAB Calculation Engine it is simulated with passing real time parameters to Chaotic Equation Sets. Thus ,both calculated numeric results and figurative results are supplied for visitors.Keywords: Chaotic Simulation Labratory, Digital Medium,MATLAB Calculation Engine,Chaotic Method

Synchronization of Unified Chaotic Systems Using Sliding Mode Controller

This paper presents a method for synchronizing the unified chaotic systems via a sliding mode controller (SMC). The unified chaotic system and problem formulation are described. Two identical unified chaotic systems can be synchronized using the SMC technique. The switching surface and its controller design are developed in detail. Simulation results show the feasibility of a chaotic secure communication system based on the synchronization of the Lorenz circuits via the proposed SMC

Design and Implementation of Secure Chaotic Communication Systems

Chaotic systems have properties such as ergodicity, sensitivity to initial conditions/parameter mismatches, mixing property, deterministic dynamics, structure complexity, to mention a few, that map nicely with cryptographic requirements such as confusion, diffusion, deterministic pseudorandomness, algorithm complexity. Furthermore, the possibility of chaotic synchronization, where the master system (transmitter) is driving the slave system (receiver) by its output signal, made it probable for the possible utilization of chaotic systems to implement security in the communication systems. Many methods like chaotic masking, chaotic modulation, inclusion, chaotic shift keying (CSK) had been proposed however, many attack methods later showed them to be insecure. Different modifications of these methods also exist in the literature to improve the security, but almost all suffer from the same drawback. Therefore, the implementation of chaotic systems in security still remains a challenge. In this work, different possibilities on how it might be possible to improve the security of the existing methods are explored. The main problem with the existing methods is that the message imprint could be found in the dynamics of the transmitted signal, therefore by some signal processing or pattern classification techniques, etc, allow the exposition of the hidden message. Therefore, the challenge is to remove any pattern or change in dynamics that the message might bring in the transmitted signal

Observer-based chaos synchronization for secure communications

Chaos, with reference to chaos theory, refers to an apparent lack of order in a system that, nevertheless, obeys particular laws or rules. The chaotic signals generated by chaotic systems have some properties such as randomness, complexity and sensitive dependence on initial conditions, which make them particularly suitable for secure communications. Since the 1990s, the problem of secure communication, based on chaos synchronization, has been thoroughly investigated and many methods, for instance, robust and adaptive control approaches, have been proposed to realize the chaos synchronization. However, from systems theory perspective, it may seem obvious that many robust and adaptive control methods could be considered for possible attacks against secure communication. In this thesis, we introduce the concept of secure chaos synchronization from the control theoretic view point. A new secure communication system, based on the chaos synchronization, is proposed and its security is analyzed, both theoretically and numerically

Yeni kaotik sistemler: Elektronik devre gerçeklemeleri, senkronizasyon ve güvenli haberleşme uygulamaları

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Anahtar Kelimeler: Kaos, Kaotik Sistemler, Tuhaf Çekici, Kaotik Devreler, Senkronizasyon, Kaotik Gizleme, Güvenli HaberleşmeKaos ve kaotik sistemler bir çok uygulama alanına sahiptir. Popüler ve pratik uygulama alanlarından biri de kaos ile güvenilir haberleşmedir. Kaotik işaretler, başlangıç şartlarına hassas bağımlıdırlar, tahmin edilemez özelliklere ve gürültü benzeri geniş yayılı spektruma sahiptirler. Bu yüzden, kaotik işaretlerin bilgi işaretini gizleme ve gürültüye bağışık kılma özelliğinden yararlanılarak değişik haberleşme uygulamalarında kullanılmaktadır. Kaos tabanlı güvenilir haberleşme sistemleri, iletilecek bilgi işaretlerinin spektrumunu geniş bir sahaya yayabilmeleri, eşzamanlı olarak bildiri işaretlerini kodlayabilmeleri ve bu işlemleri basit ve pahalı olmayan kaotik devre düzenekleriyle gerçekleştirebilmeleri sebebiyle, literatürdeki standart geniş spektrumlu haberleşme sistemlerine alternatif olmuşlardır. Güvenli haberleşmede Lorenz, Chua, Rossler, Duffing gibi klasik kaotik sistemler yaygın olarak kullanılmaktadır.Bu tezin amaçlarını; Klasik kaotik sistemlere alternatif olarak kullanılabilecek yeni kaotik sistemlerin bulunup tanıtılması, elektronik devrelerinin tasarlanması, Pecora-Carroll yöntemiyle senkronizasyon devrelerinin tasarlanması, kaotik gizleme yöntemiyle güvenli haberleşme devrelerinin tasarlanması, ve bu yeni sistemlerin güvenli haberleşmede kullanılabileceğinin gösterilmesi olarak sayabiliriz.Bu amaçlar için, önce değişik bilim dallarında mevcut olan farklı kaotik sistemler araştırılmıştır. Topolojik olarak basit fakat dinamik yapıları zengin olan ve literatürde elektronik devre gerçeklemesi, senkronizasyon ve güvenli haberleşme uygulamaları görülmeyen Yayınımsız Lorenz, Rikitake, Rucklidge, Arneodo ve Hoover(Sprott94A) sistemleri seçilmiştir. Bu sistemlerin Matlab ve Orcad programları ile, sayısal ve elektronik devre olarak, sırasıyla modellemeleri, elektronik devre gerçeklemeleri, senkronizasyon ve güvenli haberleşme uygulamaları yapılmıştır.Yine, bilgisayar programları ile yapılan sayısal simülasyonlar ve araştırmalar sonucunda hiçbir bilim dalında mevcut olmayan yeni kaotik sistemler keşfedilmiş, bunlardan yedi tanesi tanıtılmış, yedinci sistemin Matlab ve Orcad programları ile, sayısal ve elektronik devre olarak, sırasıyla modellemesi, elektronik devre gerçeklemesi ve senkronizasyon uygulaması yapılmıştır.Ayrıca, yeni keşfedilen kaotik G sistemi ile Rikitake sisteminin deneysel olarak da elektronik devreleri kurulmuş, osiloskop çıktıları verilmiştir. Son bölümde bu çalışmadan elde edilen sonuçlar tartışılmış ve değerlendirilmiştir.Key Words: Chaos, Chaotic Systems, Strange Attractor, Chaotic Circuits, Synchronization, Chaotic Masking, Secure CommunicationChaos and chaotic systems have many fields of applications. One of the popular practical application is secure communication. Chaotic signals depend very sensitively on initial conditions, have unpredictable features and noise like wideband spread spectrum. So, it can be used in various communication applications because of their features of masking and immunizing information against noise. Chaos-based secure communication systems have been alternative of the standard spread-spectrum systems, since they are able to spread the spectrum of the information signals and simultaneously encrypt the information signals with chaotic circuitry which is simple and inexpensive. In secure communication field, like Lorenz, Chua, Rossler, Duffing etc., classical systems are widely used.This thesis` aims are; finding and introducing new chaotic systems which could be used alternatively to classical chaotic systems; designing their electronic circuits, their synchronization circuits using Pecora-Carroll method, their chaotic masking communication circuits, and showing that these chaotic systems could be used in secure communication area.Towards these aims, firstly chaotic systems from different science disciplines were investigated. From these investigated systems, Diffussionless Lorenz, Rikitake, Rucklidge, Arneodo and Hoover(Sprott94A) systems were choosen. These chaotic systems are topologicaly simple but their dynamical behaviours are very rich and their synchronization and secure communication applications were not seen in literature. Using Matlab-Simulink and Orcad-Pspice programs, their modelings, electronic circuit implementations, synchronization and secure communication applications were realized, both numerically and as electronic circuit, respectively.Also, by performing simulations and researches using computer programs, new chaotic systems which didn?t exist in any science disciplines, were discovered. Seven of these were introduced. Using Matlab-Simulink and Orcad-Pspice programs, seventh system?s modeling, electronic circuit implementation, synchronization and secure communication application were realized, both numerically and as electronic circuit, respectively.Furthermore, experimental electronic circuits of the newly discovered chaotic G system, and Rikitake system were implemented and their oscilloscope outputs were given.Results obtained in this study have been discussed and evaluated in the last chapter

Digital Communication System with High Security and High Immunity

Today, security issues are increased due to huge data transmissions over communication media such as mobile phones, TV cables, online games, Wi-Fi and satellite transmission etc. for uses such as medical, military or entertainment. This creates a challenge for government and commercial companies to keep these data transmissions secure. Traditional secure ciphers, either block ciphers such as Advanced Encryption Standard (AES) or stream ciphers, are not fast or completely secure. However, the unique properties of a chaotic system, such as structure complexity, deterministic dynamics, random output response and extreme sensitivity to the initial condition, make it motivating for researchers in the field of communication system security. These properties establish an increased relationship between chaos and cryptography that create strong and fast cipher compared to conventional algorithms, which are weak and slow ciphers. Additionally, chaotic synchronisation has sparked many studies on the application of chaos in communication security, for example, the chaotic synchronisation between two different systems in which the transmitter (master system) is driving the receiver (slave system) by its output signal. For this reason, it is essential to design a secure communication system for data transmission in noisy environments that robust to different types of attacks (such as a brute force attack). In this thesis, a digital communication system with high immunity and security, based on a Lorenz stream cipher chaotic signal, has been perfectly applied. A new cryptosystem approach based on Lorenz chaotic systems was designed for secure data transmission. The system uses a stream cipher, in which the encryption key varies continuously in a chaotic manner. Furthermore, one or more of the parameters of the Lorenz generator is controlled by an auxiliary chaotic generator for increased security. In this thesis, the two Lorenz chaotic systems are called the Main Lorenz Generator and the Auxiliary Lorenz Generator. The system was designed using the SIMULINK tool. The system performance in the presence of noise was tested, and the simulation results are provided. Then, the clock-recovery technique is presented, with real-time results of the clock recovery. The receiver demonstrated its ability to recover and lock the clock successfully. Furthermore, the technique for synchronisation between two separate FPGA boards (transmitter and receiver) is detailed, in which the master system transmits specific data to trigger a slave system in order to run synchronously. The real-time results are provided, which show the achieved synchronisation. The receiver was able to recover user data without error, and the real-time results are listed. The randomness test (NIST) results of the Lorenz chaotic signals are also given. Finally, the security analysis determined the system to have a high degree of security compared to other communication systems