BER performance improvement for secure wireless communication systems based on CSK- STBC techniques

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 very low bit error rates (BER) along with information security. This paper investigates the feasibility of using chaotic communications over Multiple-Input Multiple-Output (MIMO) channels by combining chaos modulation with a suitable Space Time Block Code (STBC). It is well known that the use of Chaotic Modulation techniques can enhance communication security. However, the performance of systems using Chaos modulation has been observed to be inferior in BER performance as compared to conventional communication schemes. In order to overcome this limitation, we have proposed the use of a combination of Chaotic modulation and Alamouti Space Time Block Code. We have studied the performance of Chaos Shift Keying (CSK) with 2×1 Alamouti scheme for different chaotic maps over Additive White Gaussian Noise (AWGN) and Rayleigh fading channels. Our simulations indicate that the use of the Alamouti schemes can allow service providers to enhance security without degrading the BER performance while communicating over these channels.