| 摘要 |
<p>A method of data transmission for a cable television system comprises the steps of transmitting data via a plurality of signals including, but not limited to, in-band audio, in-band video and out-of-band signals. The in-band data signals are transmitted on scrambled or non-scrambled channels. In in-band video data transmission, the method comprises the further steps of selecting certain lines of the vertical blanking interval for in-band video data transmission, omitting certain equalizing pulses during the selected lines and inserting in-band video data during the selected lines. The several data signals, in-band and out-of-band, have compatible transaction formats to facilitate decoding and data storage processes at a subscriber terminal (300) of the cable television system. Data transmission apparatus (100) comprises a data inserter (107a) for inserting in-band data in non-scrambled channels, an addressable data transmitter (140) for transmitting out-of-band and a scrambler (104) for inserting data in scrambled channels.</p> |
