US 6,788,787 B1 · Pseudorandom number generator, stream encryption method, and stream encrypting communication method

Abstract

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).

Claims11

Dependent claims

A pseudorandom number generator comprising:

a one dimensional mapping circuit for generating chaos having non-linear input-output characteristics;
an AD converter for converting an analog output of the one dimensional mapping circuit;
a sample-and-hold circuit for holding and outputting a digitally converted value from the AD converter in response to an external clock;
and
a DA converter for outputting an analog converted value in response to the output of the sample-and-hold circuit as feedback to the one dimensional mapping circuit,
wherein quantizing divisions of at least one of the AD converter and the DA converter are made non-linear, and further wherein a binary stream is output responsive to the output of the sample-and-hold circuit.

3 more elements

A pseudorandom number generator comprising:

a chaos-generating loop comprising a pair of one dimensional mapping circuits for generating chaos having non-linear input-output characteristics, a pair of CMOS switches which alternately open and close an output side path of the one dimensional mapping circuits, in synchronization with an external clock, and a pair of feedback loops that cross-connect the analog outputs of each of the one dimensional mapping circuits, via the CMOS switches, as feedback to the inputs of the other of the one dimensional mapping circuits;
and
a pair of AD converters that perform digital conversion of the analog outputs of the one dimensional mapping circuits that are extracted via the CMOS switches,
wherein in the chaos-generating loop, according to the elapse of the discrete time established by an external clock, the outputs of the one dimensional mapping circuits are alternately mapped, so as to output, via each of the AD converters, a binary sequence that is a chaos stream.

1 more element

Dependencies are inferred from the claim text.

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

Life of this patent

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

Life of this patent

Abstract

Claims11