CIRCUIT FOR CHECKING BIT ERRORS IN A RECEIVED BCH CODE SUCCESSION BY THE USE OF PRIMITIVE AND NON-PRIMITIVE POLYNOMIALS

摘要

PURPOSE:To reduce considerably the capacity of an ROM and to improve a decoder, by using the quotient remainder of a primitive polynomial as the address information of the ROM and then comparing the output of the ROM with the quotient remainder of another polynomial. CONSTITUTION:A feedback register 5 divides a receiving data with a polynomial having a primitive root of a polynomial g1(x) of a BCH (Bose-Chaudhuri-Hocquenghem) code and delivers the quotient remainder. While a feedback register 6 divides the receiving data with the 2nd polynomial containing the factors other than those contained at least in the 1st polynomial among the factors of a grown polynomial g3(x) of the BCH code and delivers the quotient remainder. The quotient remainder, i.e., the output of the register 5 is used as an address input for an ROM3. Then the coincidence is detected by a coincidence detecting circuit 7 between the output of the ROM3 and the quotient remainder, i.e., the output of the register 6.