Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
3 results
Search Results
Item Hybrid LDPC-STBC communications system based on chaos(Association for Computing Machinery, 2019) Abdulameer, L.F.; Jignesh, J.D.; Sripati, U.; Kulkarni, M.This paper attempts to show a communication strategy of implementing a hybrid of Low-Density Parity Check (LDPC) and Multiple Input Multiple Output (MIMO) based on chaotic technique. Many chaotic techniques which consider a significant part in the information security schemes was proposed, but one of the greatest defy in chaotic communications is the limitation of the system performance due to realistic channel conditions. We have investigated the theory and carried out detailed analysis pertaining to encoding/decoding of chaotic modulation schemes, the use of suitable LDPC coded MIMO schemes for providing secure and reliable communication. The aim of the hybrid scheme is that a correctly designed coded Space Time Block Code (STBC) is used to mitigate the declination of the signal caused by multipath scattering. The Bit-Error Rate (BER) performance of this hybrid scheme with two transmit antennas and two receive antennas under Rayleigh fading model is evaluated. The results indicate that that implementing LDPC (regular and irregular) coded STBC system decrease BER as compared with systems without implementing LDPC code for chaotic communication systems. Mathematical analysis for the hybrid system has been derived and achieved using Matlab. © 2019 Association for Computing Machinery.Item BER performance enhancement for secure wireless optical communication systems based on chaotic MIMO techniques(2014) Abdulameer, L.F.; Jignesh, J.D.; Sripati, U.; Kulkarni, M.There has been a growing interest in the use of chaotic techniques for enabling secure communication in recent years. This need has been motivated by the emergence of a number of wireless services which require the channel to provide low bit error rates (BER) along with information security. The aim of such activity is to steal or distort the information being conveyed. Optical Wireless Systems (basically Free Space Optic Systems, FSO) are no exception to this trend. Thus, there is an urgent necessity to design techniques that can secure privileged information against unauthorized eavesdroppers while simultaneously protecting information against channel-induced perturbations and errors. Conventional cryptographic techniques are not designed for protecting information integrity when data is being transferred over a harsh communication medium. Hence, a separate channel coding protocol is often necessary to achieve this goal. Our work indicates that the use of a suitable Chaotic Shift Keying (CSK) map combined with an appropriate Space-Time Code (STC) can allow both requirements to be met. In this paper, we have concentrated on investigating the error rate performance of chaotic-wireless optical communication links operating over atmospheric channel, where the turbulence-induced fading is described by the Gamma-Gamma and log-normal distributions. The main aim of the paper is to assess the feasibility of employing Space-Time Coded chaotic communications over Multiple Input Multiple Output (MIMO) communication channels. Our simulations indicate that the combination of the STC and tent map provides the best BER performance in addition to security when compared to the choice of other maps. © 2013 Springer Science+Business Media Dordrecht.Item BER Performance Improvement of Dual Chaotic Maps Based on STBC Communication System(University of Baghdad, 2022) Abdulameer, L.F.; Sripati, U.; Kulkarni, M.Sensitive information of any multimedia must be encrypted before transmission. The dual chaotic algorithm is a good option to encrypt sensitive information by using different parameters and different initial conditions for two chaotic maps. A dual chaotic framework creates a complex chaotic trajectory to prevent the illegal use of information from eavesdroppers. Limited precisions of a single chaotic map cause a degradation in the dynamical behavior of the communication system. To overcome this degradation issue in, a novel form of dual chaos map algorithm is analyzed. To maintain the stability of the dynamical system, the Lyapunov Exponent (LE) is determined for the single and dual maps. In this paper, the LE of the single and dual maps have been computed numerically. Increasing the dynamical behavior of the system by using more complex chaotic maps leads to inferiority in the overall system performance. So, in this work, the BER performance for the dual and single chaotic maps by exploiting the benefits of a hybrid Chaos Shift Keying-Multiple-Input-Multiple-Output (CSK-MIMO) communication system has been investigated. The results show that the dual tent map has more randomness, whereas the single logistic map has the least randomness. As well as the CSK-MIMO gives an outstanding BER performance when it compared with the SISO system which helps in reducing the system’s inferiority. © 2022, University of Baghdad. All rights reserved.
