Pseudorandom number generator, stream encryption method, and stream encrypting communication method

摘要

A chaos-generating loop includes a one dimensional mapping circuit (13) with non-linear input-output characteristics for generating chaos, a linear or non-linear AD converter (15) for converting an analog output of the one dimensional mapping circuit (13) to digital form, a sample-and-hold circuit (17) for holding and outputting the digitally converted value from the AD converter (15), in response to an external clock (C), and a linear or non-linear DA converter (19) for converting an output of the sample-and-hold circuit (17) to analog form and outputting this analog signal to the one dimensional mapping circuit (13), and a decoder for outputting a chaos stream in response to the output of the sample-and-hold circuit (17).