Patent · US Expired

Method and apparatus for verifying CRC codes

US5778013A · kind A · utility

77Cited by
7References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 11, 1996
Grant dateJul 7, 1998
Priority date
Expiry dateJan 11, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M13/091
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

Apparatus for verifying a CRC code of a message transmitted as a succession of sub-blocks comprises dedicated hardware including a linear feedback shift register for deriving a `partial` CRC code for each individual sub-block. These partial CRC codes are held in a store for subsequent combination under software program control. The combination is performed in a iterative manner, each partial CRC code being added modulo 2 to values selected from look-up tables in accordance with the result of the previous step of the iteration. The division of the CRC verification into two operations and the use of precalculated look-up tables facilitate the efficient, simultaneous reception of many messages having interleaved sub-blocks without incurring serious time penalties.

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