The table headings are:
Block inner | outer code | outer | inner code # code | erasures | code | changes changes|1st 2nd 3rd 4th | changes | 0 1 2 3 4 ---- ------ |--- --- --- --- | --- | --- --- --- --- ---
Below is a list of each of the above column headings, from left to right, and an explanation of what is meant by each column heading.
This is an index, starting with 0, used to internally number the outer code blocks.
This is a total of how many of the sub-carriers had their phase changed by the inner decoder, in its attempt to correct as many errors as it could.
An "erasure" means that an error has probably been detected, but not corrected. The sub-headings "1st, 2nd, 3rd, and 4th" show how four different categories of erasures, detected by the inner decoder, are to be used by the outer decoder.
All those in the "1st" column are to be used 1st, followed by those in the "2nd" column, followed by those in the "3rd" column, followed by those in the "4th" column. The erasures in the "1st" column result from the received combination of phases being too far away from all code words, even when 4 of the 8 sub-carriers are ignored. The erasures in the 4th column are close enough to the same code word when both 3 and 4, of the 8 sub-carriers, are ignored.
This is a count of the number of symbols corrected by the outer decoder. A negative number means that the outer decoder recognized that it could NOT decode the block correctly.
The five sub-headings, "0, 1, 2, 3, and 4" indicate how many of the 8 sub-carriers were changed by the inner decoder. The numbers in the table are how many of the symbols (in each block) had the respective number of sub-carriers changed by the inner decoder.
Thus, the sub-heading "0" is for the case of error free symbols (0 of the 8 sub-carriers were changed by the inner decoder.)
The last column has no heading. The possible symbols in this column are:
which means all errors were corrected
which means not all errors were corrected
which means an illegal symbol was present in the decoded output
All "+" symbols in the last column means all errors were successfully corrected. Anything else, means not all errors were corrected.