Patent · US Expired

Audio scrambling system for scrambling and descrambling audio signals

US5617476A · kind A · utility

9Cited by
10References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 12, 1994
Grant dateApr 1, 1997
Priority date
Expiry dateOct 12, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04K1/02
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A scrambling system has a scrambling apparatus and a descrambling apparatus for scrambling and descrambling a digital audio signal having a plurality of 16-bit long sample data units. The scrambling apparatus has a detector for detecting, in each sample data unit, a meaningless portion which is a portion including the MSB and a meaningful portion which is a portion including the LSB, and applying scrambling only to the meaningful portion. Since the meaningless portion is not scrambled, no error data will appear in the meaningless portion. Thus, an unexpected abrupt change in sound caused by a bit error in the meaningless portion which has bits with greater weighted value can be avoided.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.