Chaotic Synchronization and Secure Communication Using Contraction Theory

  • Bharat Bhushan Sharma
  • Indra Narayan Kar
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5909)


Here, observer based synchronization and secure communication scheme is presented for chaotic systems. In proposed scheme, extended Kalman filter based receiver is selected for given transmitter system. The stability results are derived using virtual system concept. Observer gains for synchronization are obtained as a solution of matrix Riccati equation. For secure communication, n-shift ciphering algorithm is used with one of the chaotic state chosen as key. Numerical simulations are presented in the end to verify the efficacy of proposed scheme.


Synchronization Observer Secure Communication 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Bharat Bhushan Sharma
    • 1
  • Indra Narayan Kar
    • 1
  1. 1.Department of Electrical EngineeringIndian Institute of Technology, DelhiNew DelhiIndia

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