| 摘要 |
<p>A signal access mode control method for wanted signals such as image signals (IMAGE), whereby a user remotely selects a wanted signal access mode. A first access mode comprises providing the user with an original wanted signal (IMAGE), and a second access mode comprises alternately and periodically transmitting to the user the wanted signal and a distortion signal (MIRE, IT) in a distorted signal. The distorted signal is still intelligible so that the user can ascertain the contents of the wanted signal and optionally select the first access mode. Different charging modes are provided for the two access modes. Physical embodiments for implementing the method are provided for switching node switching matrices (GC) in a centralised architecture, and digital distribution networks in a more futuristic distributed architecture.</p> |
