th memory address of the buffer section of the m th data item for example for the 57th input to calculate the buffer address of the 14th data item the remainder w 14 57 0 is derived from 57 14 u00d7 4 1 first hence the 14th data item of the 57th data cluster is to be buffered in the 57th memory address of the 14th buffer section derived by 14 u00d7 4 1 57 for the 100th input and the 14th data item the remainder w 14 100 43 is derived from 100 14 u00d7 4 1 hence the 14th data item of the 100th data cluster should be buffered in the 43 th memory address of the 14 th data buffer section moreover when the interleaver 22 outputs data the access control unit 204 provides a reading address sequence to allow the interleaver 22 to interleave and read the buffered data in the memory 24 the reading address sequence is based on the remainder r m l derived by the output sequence l plus 1 and divided by m u00d7 dm pm namely the m th data item of the l th output data is read from the r m l memory address of the m th buffer section when the remainder r m l is zero the reading address is the m u00d7 dm pm th memory address of the buffer section of the m th data item as previously discussed for the 57 th output to calculate the reading address of the buffer address of the 14 th data item the remainder r 14 57 1 is derived from 57 1 14 u00d7 4 1 hence during the 57 th output data buffered in the first memory address.