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Machine translation
1. (WO1980002901) TELEVISION SYSTEM WITH ACCESS CONTROL USING A VARIABLE ELECTRONIC KEY
Latest bibliographic data on file with the International Bureau   

Pub. No.:    WO/1980/002901    International Application No.:    PCT/FR1980/000090
Publication Date: 24.12.1980 International Filing Date: 06.06.1980
IPC:
H04N 7/16 (2011.01)
Applicants:
Inventors:
Priority Data:
7915400 15.06.1979 FR
Title (EN) TELEVISION SYSTEM WITH ACCESS CONTROL USING A VARIABLE ELECTRONIC KEY
(FR) SYSTEME DE TELEVISION A CONTROLE D"ACCES UTILISANT UNE CLE ELECTRONIQUE VARIABLE
Abstract: front page image
(EN)Television system with a double key: a service key (K) is used for scrambling the transmission and a key (Ci) defines the subscription. For each key (K) corresponds as many messages (Mi) as there are keys (Ci) and these messages are transmitted by a DIDON process to the receivers. The receivers return the service key (K) and unscramble the signals. Application to toll television.
(FR)Systeme de television a controle d"acces. Le systeme de l"invention est a double cle: une cle de service K sert a brouiller l"emission et une cle Ci definit l"abonnement. A chaque cle K on fait correspondre autant de messages Mi qu"il y a de cles Ci et on transmet ces messages par une procedure DIDON vers les recepteurs. Ceux-ci restituent la cle de service K et debrouillent le signal. Application a la television a peage.
Designated States:
Publication Language: French (FR)
Filing Language: French (FR)