Abstract: A parametervarying chaotic encryption scheme based on spatiotemporal twodimensional chaos sequence is proposed in this paper. Oneway coupled mapping lattice model was first used to generate spatiotemporal chaos binary sequence and each performance of the sequence was analyzed, which proves that the chaos sequence has a good pseudorandomicity. On the basis of this, a new parametervarying chaotic encryption algorithm was adopted, with the generated spatiotemporal chaos binary sequence as the original encryption key, to realize the parametervarying chaotic encryption through randomly changing the original parameter, iteration times and system parameter of the chaotic encryption system. Experimental results prove that the random varying of parameters in the chaotic encryption system can increase the complexity and long periodicity of the chaos sequence, so that it has the advantage of fastspeed encryption and high security.

Key words: spatiotemporal chaos, binary sequence, pseudorandomicity, secret key