TRANSMITTER, RECEIVER, TRANSMITTING METHOD AND RECEIVING METHOD

摘要

PROBLEM TO BE SOLVED: To improve the safety in a restricted receiving system and a restricted reproducing system.

SOLUTION: A transmitter scrambles a program signal by using a scramble key to allow a viewer previously set to view the program signal, and multiplexes the scrambled signal with the scramble key and transmits them. This transmitter has a divider for dividing the scramble key used for scramble of the program signal on the basis of the previously set number of bits, an ECM encrypting section for adding the scramble key divided by the divider to a different ECM and encrypting it, and a multiplexer for multiplexing the scrambled program signal with the ECM encrypted by the ECM encrypting section and transmitting them. Thus, the above problem is solved.

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