CREATION OF PSEUDO-RANDOM SEQUENCES BASED ON CHAOS FOR FORMING OF WIDEBAND SIGNAL

Abstract

Background. Telecommunication systems with a broadband signal have improved noise immunity, the ability to receive a signal in multipath, as well as electromagnetic compatibility with neighboring radio electronic devices. The use of known pseudo-random sequences to create systems doesn’t ensure their high confidentiality due to the possibility of their selection when receiving a signal. A significant increase in the confidentiality of the system can be achieved by using pseudorandom sequences based on chaos.Objective. The aim of the paper is the development of a technique for creating pseudo-random sequences based on chaos, as well as the analysis of the correlation characteristics of pseudo-random sequences formed on the basis of a chaotic signal.Methods. Chaotic signals are inherently pseudo-random, but they are generated by deterministic systems. All computer models of chaos are approximations of mathematical chaos. Any analysis of these sequences doesn’t allow them to bereproduced and they can’t be intercepted, so they have significant advantages when used for spreading the signal spectrum and creating a pseudo noise broadband signal. Sequence selection with an acceptable level of side lobes of the autocorrelation function is carried out by using the developed graphical interface method.Results. It is shown that, based on the chaos of pseudo-random sequences, it is possible to select sequences with side lobe level up to 0.3, suitable for practical use after analysis of their autocorrelation functions.Conclusions. Using created chaos based pseudo-random sequences is effective for building broadband single-channel telecommunication systems that have a high degree of confidentiality in the information transmission.Keywords: broadband signal; chaos; pseudorandom sequence; autocorrelation function; confidentiality of information transmission.