| 摘要 |
PROBLEM TO BE SOLVED: To obtain a scrambling system capable of preventing the generated pattern of a pseudo random signal required for scrambling form being estimated. SOLUTION: A payload 1st byte extract section 15 extracts a 1st byte of a payload. A key outputted from a key generating section 17, the 1st byte of a payload extracted by the payload 1st byte extract section 15 and a count extracted by a cyclic counter extract section 13 are fed respectively to a key correction section 18, and a key loaded to a PN signal generating section 19 is corrected based on the signals to change a key loaded to the PN signal generating section 19 for each TS packet. Thus, the security is enhanced. A PN signal passing through an AND gate 20 and the TS are exclusively ORed in an adder 21, from which the TS scrambled by the PN signal is outputted. |
