Hyperchaotic system‐based pseudorandom number generator

Pseudorandom sequences are very important in the field of cryptography. The characteristics such as non‐linearity and random‐like behaviours make chaotic systems suited to generate pseudorandom sequences. However, most of chaos‐based pseudorandom number generators have a typical shortcoming. That is, the finite precision in all processors may cause the chaotic systems to degenerate into a periodic function or a fixed point. To overcome this shortcoming, a hyperchaos‐based generator is proposed. First, a new hyperchaotic system with bigger Lyapunov exponent is constructed. Then the self‐shrinking generator, which is superior to many other linear feedback shift register‐based generators, is used to perturb the hyperchaotic sequences to decrease the period degeneration and improve the performance of the sequences. The proposed generator is named as hyperchaos with self‐shrinking perturbance generator (H‐SSP generator). The analysis results show that the H‐SSP generator has better performance.