| 摘要 |
<p>An independant scrambling unit (1) for a digital audiovisual transmission system, the scrambling unit (1) comprising an input for receiving an assembled transport packet stream from a physically seperate multiplexer (4), a scrambling device for scrambling the received transport stream according to a randomising control word and an output for sending the scrambled transport stream to a transmitter means for subsequent transmission. The scrambling unit (1) may also be used to introduce other packet data in the data stream.</p> |
