Patent ID: 6208697
Filing Date: 2001-03-27
Classification: H04L

Abstract:
A channel code converter including table means storing the combinations of channel bits of a bit number larger than a predetermined bit number assigned from the combinations of data bits of said predetermined bit number, in order to convert the codes of data bits of said predetermined bit number into said channel bits using said table means and to record the data according to an NRZ (non-return to zero) rule, wherein said table means comprises:a first table for storing the data satisfying predetermined conditions, the data satisfying predetermined conditions being those data having a pattern in which the same bits are continuing by not less than 2 bits in the head portion and in the last portion among the patterns in which the same bits are necessarily continuing by not less than 2 bits except in the head portion and in the last portion of the data stored in the table means among the channel bits, the same bits are necessarily continuing by not more than k bits (k is a positive integer) except in the head portion and in the last portion, and the same bits are continuing by not more than (k-1) bits in the head portion and in the last portion;a second table for storing the data of a pattern in which the head portion starts with either ""01"" or ""10"" and the same bits are continuing by not less than 2 bits in the last portion among the patterns in which the bits are continuing by not more than (k-1) bits;a third table for storing the data in which the same bits are continuing by not less than 2 bits in the head portion, and the last portion ends with ""01"" and ""10"" among the patterns in which the bits are continuing by not more than (k-1) bits; anda fourth table for storing the data of a pattern in which the head portion starts with either ""01"" or ""10"" and the last portion ends with either ""01"" or ""10"" among the patterns in which the bits are continuing by not more than (k-1) bits;said channel code converter further including:selection means for selecting any one of said first table to said fourth table so as to start with a channel bit data same as the final bit of one channel bit before and so as to end with a channel bit data same as the start bit of one channel bit after, so that the continuing data bits of a data stream converted inclusive of a connection portion between said channel bits are not smaller than 2 bits but are not larger than k bits.