Design of the nonlinear look-up table in the chaotic pseudorandom number generator based on augmented Lorenz map

Abstract

A chaos-based stream cipher using an augmented Lorenz map has been proposed. It was shown through numerical simulations that this chaotic map can generate statistically secure pseudorandom numbers, although high-speed hardware is necessary for practical use. One of the problems in digital hardware realization is implementation of the nonlinearities included in the map. In this paper, we propose a nonlinear look-up table (LUT) technique to implement the sine function considering the distribution of the argument variable. We experimentally demonstrate through field programmable gate array(FPGA) prototyping, high-speed and small-sized digital hardware implementation of the pseudorandom number generator based on the augmented Lorenz map using the proposed nonlinear LUT method.