Global Patent Index - EP 0750821 A4

EP 0750821 A4 19970723 - DATA DECRYPTION APPARATUS IN A SUBSCRIPTION TELEVISION SIGNAL RECEIVING SYSTEM

Title (en)

DATA DECRYPTION APPARATUS IN A SUBSCRIPTION TELEVISION SIGNAL RECEIVING SYSTEM

Title (de)

DATENENTSCHLÜSSELUNGSVORRICHTUNG IN EINEM ABONNEMENT-FERNSEHEMPFANGSSYSTEM

Title (fr)

APPAREIL DE DECRYPTAGE DE DONNEES DANS UN SYSTEME RECEVANT DES SIGNAUX TELEVISUELS CHEZ UN ABONNE

Publication

EP 0750821 A4 19970723 (EN)

Application

EP 94914715 A 19940318

Priority

  • BR 9408551 A 19940318
  • US 9402979 W 19940318

Abstract (en)

[origin: WO9526107A1] A receiver of satellite-broadcast signals including high definition television signals includes apparatus (12-26) for decrypting encrypted signals. When unencrypted "plaintext" signal information which is not to be decrypted is received, the plaintext information is applied to the decrypting apparatus. Normal decrypting operation is modified so that the input plaintext information appears as unaltered plaintext information at the output of the decrypting apparatus. A bit selection network (628; S1, ... S8) associated with a decipher function (f(R,K)) of the decryption apparatus employs a combinational logic network (18, 628) rather than Look up Tables.

IPC 1-7

H04N 7/167

IPC 8 full level

H04H 20/76 (2008.01); H04L 9/06 (2006.01); H04N 7/167 (2011.01)

CPC (source: EP)

H04L 9/0625 (2013.01); H04N 7/1675 (2013.01); H04L 2209/125 (2013.01); H04L 2209/24 (2013.01); H04L 2209/34 (2013.01); H04L 2209/601 (2013.01)

Citation (search report)

  • [X] WO 9013207 A1 19901101 - SCIENTIFIC ATLANTA [US]
  • [A] WO 9311638 A1 19930610 - SCIENTIFIC ATLANTA [US]
  • [X] PATENT ABSTRACTS OF JAPAN vol. 017, no. 511 (E - 1432) 14 September 1993 (1993-09-14) & US 5414456 A 19950509 - ODA OSAMU [JP], et al
  • [A] MATSUMOTO H ET AL: "ENCRYPTION BOARD FOR ITU-T STANDARD AUDIOVISUAL SERVICES", NTT REVIEW, vol. 6, no. 2, 1 March 1994 (1994-03-01), pages 32 - 38, XP000446891
  • See references of WO 9526107A1

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

WO 9526107 A1 19950928; AU 6696994 A 19951009; BR 9408551 A 19970819; EP 0750821 A1 19970102; EP 0750821 A4 19970723; JP H09510593 A 19971021

DOCDB simple family (application)

US 9402979 W 19940318; AU 6696994 A 19940318; BR 9408551 A 19940318; EP 94914715 A 19940318; JP 52461095 A 19940318