Patent ID: 6519737
Filing Date: 2003-02-11
Classification: H03M

Abstract:
A method for computing a cyclic redundancy code (CRC) for use in a communication data stream M bits at a time for an input sequence u(n) whose length is not a multiple of M, comprising:(i) representing a frame of data to be protected as the input sequence; (ii) determining a CRC for said input sequence M bits at a time from a state vector, until a last block of said input sequence is reached; (iii) if said last block of said input sequence is full, then determining said CRC to be a completed CRC; and (iv) if said last block of said input sequence is not full, then: (a) setting a number of the last bits of said last block equal to zero; (b) processing said last block, padded with said number of last bits equal to zero, according to steps (i) and (ii) to determine a new CRC (yCRC); and (c) running said state vector backwards in time to determine a completed CRC.