A Chaotic-Based Pseudo-Random Bit Generator for Navigation Applications

In this paper, we propose a novel method to generate pseudo-random-noise (PRN) bits for navigation applications. In the present method, the code sequence generator is constructed based on two chaotic logistic maps running parallel and starting from independent initial conditions. The logistic map is a simple mathematical model that shows bewildering complex behavior. By appro-priately setting the initial conditions, the PRN sequence is then generated by comparing the outputs of both logistic maps. Several simulations are set up to verify the correlation properties of the pseudo-random bit generator (PRBG). The result shows that the code sequences generated by the proposed PRBG have great auto- and cross-correlation properties, which are very similar to the PRN sequences used by GPS navigation system. The RPBG sequences are therefore suitable for signal ranging that is used comprehensively in the navigation system. On the other hand, the chaotic nature of the proposed PRBG codes can provide more secure communication than the traditional PRN sequences. The proposed PRN sequences are well suitable to be incorporated with the so-called chaotic shift keying (CSK) modulation.