| 摘要 |
<p>Data to be recorded on a magnetic disk is binary encoded including standard error control coding. The data is divided into contiguous blocks and mapped into a sequence of complex numbers according to a predetermined set of coding rules. The mapped data is then recorded on the odd and even tracks on the disk in substantially orthogonal assignments. The orthogonalization technique is used to reduce if not avoid entirely off track interference. Where it is desired to read data from an even track but the head infringes on one of its odd neighbors, the head reads a slightly weaker signal from the desired even track, because the head is not completely over it, and a weak signal from the neighboring odd track. The interfering signal from the odd track does not appear as noise in the even entries of the post inverse Fourier transform sequence, which is used for decoding.</p> |
