| 摘要 |
PURPOSE:To allow correction at the time of wrong recording words due to two- dimensional dropout of a recording word by changing a parity generating string and adding double parity words. CONSTITUTION:A word W of 16 bits through an A/D convertor 1, register 2, etc., is delayed by the time multiplied by integers of word frame length by a RAM5 whose reading is controlled, an interleave and a scamble are controlled and 16 words, etc., are recorded in 16 tracks 16-1-16-16, etc. At the same time a parity generating circuit 4 calculates parity words PA and QB based on the specific expression and parity words PB and QA of a generating string based on the other expression, and these double words PA, QA, PB and QB are recorded in tracks 16-17-16-20. By these double parities and scrambles, correcting ability can be increased, and word errors due to two-dimensional dropout, etc. by correction of plural times can be corrected. |
