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Title:
SCRAMBLER DEVICE
Document Type and Number:
Japanese Patent JP3120579
Kind Code:
B2
Abstract:

PURPOSE: To provide the scrambler device applying the effective control of signal mixing to a signal including data subjected to variable length coding and fixed length coding with respect to the scrambler to a digital signal.
CONSTITUTION: A code detector 1 has a capability discriminating the entire code in an input signal to discriminate which order bit signal of which data a signal received at present corresponds, and detects a code word subject to fixed length coding and outputs its timing to a control circuit 2. The control circuit 2 decides whether or not the bit is to be scrambled according to the setting mode and adds a random number from a random number generator 3 to the input signal when the signal is scrambled. Thus, only specific data are scrambled.


Inventors:
Noboru Katsuta
Hironori Murakami
Seiji Nakamura
Susumu Ibaraki
Application Number:
JP19939292A
Publication Date:
December 25, 2000
Filing Date:
July 27, 1992
Export Citation:
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Assignee:
Matsushita Electric Industrial Co., Ltd
International Classes:
G11B20/10; G09C5/00; H04L9/00; H04L9/10; H04L9/12; H04L9/20; H04N5/92; H04N7/167; H04N21/2347; (IPC1-7): H04L9/20; G09C5/00; G11B20/10; H04N5/92; H04N7/167
Domestic Patent References:
JP690451A
Other References:
中村高雄 他;“暗号化レベル可変なMPEG向きスクランブル方式の一考察”電子情報通信学会技術研究報告 IT95−45〜49 Vol.95,No.474(1996.1.20)p.19−24
勝田昇 他;“MPEG映像に適したスクランブル効果制御方式”テレビジョン学会技術報告 Vol.19,No.10(1995.2.16)p.7−12
勝田昇 他;“圧縮画像に適したディジタルスクランブルの一方式”電子情報通信学会技術研究報告 ISEC92−57〜63 Vol.92,No.355(1992.12.7)p.19−28
勝田昇 他;“映像信号のディジタルスクランブルの一方式”電子情報通信学会技術研究報告 ISEC90−33〜37 Vol.90,No.364(1990.12.18)p.1−6
橋間明生 他;“衛星通信M方式スクランブルシステム”National Technical Report 第36巻,第6号(平成2.12.18)p.676−684
Attorney, Agent or Firm:
Fumio Iwahashi (2 others)



 
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