PROTECTING METHOD FOR PSEUDO-RANDOM SIGNAL

摘要

PURPOSE: To make the decoding of a person decoding a cipher against a pseudo random(PN) signal 309 to be difficult by guiding non-linearity to a linear feedback shift register(LFSR). CONSTITUTION: The method is to protect the PN signal 303 generated in a PN signal generator from a cipher attack. Non-linearity is guided into the PN signal in terms of determinism, a bit pattern in terms of determinism 305 is generated and the bit pattern in terms of determinism is substituted for the PN signal 303.