Method and apparatus for encoding and decoding error correction codes in a radio communication system

A communication device (140) for receiving and decoding a codeword of predetermined length, wherein the codeword includes information and parity bits, comprises a memory (315) for storing the codeword in the form of segments, wherein each segment comprises multiple bits forming bit combinations. A first look-up table (326, 327, 328, 329) included in the communication device (140) stores parity vectors corresponding to the bit combinations, and a second look-up table (325) stores values corresponding to syndrome vectors. A processing unit (310) coupled to the memory (315) and the first and second look-up tables (325-329) uses the bit combinations of the segments as indices into the first look-up table (326-329) to locate corresponding parity vectors, adds the corresponding parity vectors using modulo 2 arithmetic to form a resulting syndrome, and uses the resulting syndrome as an index into the second look-up table (325) to locate an erroneous bit included in the codeword. In similar manner, the communication device (140) can encode parity bits into the codeword using the reduced-processing method.