NAVIGATION SYSTEM FOR A MULTICHANNEL DIGITAL TELEVISION SYSTEM

VIEWED FROM ONE ASPECT, THE PRESENT INVENTION PROVIDES A DIGITAL TELEVISION SYSTEM COMPRISING A TRANSMISSION MEANS FOR TRANSMITTING A PLURALITY OF TELEVISION CHANNELS AND A DECODER FOR RECEIVING THE PLURALITY OF CHANNELS AND CHARACTERISED IN THAT ONE CHANNEL IS USED TO CARRY AUDIOVISUAL INFORMATION (100) REGARDING PROGRAMMES OR SERVICES AVAILABLE ON SOME OR ALL OF THE OTHER CHANNELS, THE DECODER BEING ADAPTED TO GENERATE AND DISPLAY INTERACTIVE MESSAGES (101) SUPERIMPOSED OVER AND SYNCHRONISED WITH THE INFORMATION REGARDING SOME OR ALL OF THE OTHER CHANNELS.FROM ANOTHER ASPECT THE SYSTEM IS CHARACTERISED IN THAT THE DECODER IS ADAPTED TO DISPLAY A SERVICE MENU (61) PROVIDING ACCESS TO ONE OR MORE CHANNELS OR SERVICES CHANNEL, ACCESS TO ONE OR MORE OF SAID CHANNELS OR SERVICE CHANNELS PROCEEDING VIA AT LEAST ONE SUBSIDIARY MENU ACCESSED BY THE SERVICE MENU.FIGURE 10