Time-varying maximum-transition-run codes for data channels

Claim 2

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein the block code has a state transition matrix of: ##EQU8##

Claim 3

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein the block code has a state transition matrix of:

Claim 4

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein the block code has a state transition matrix of:

Claim 5

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein code has a state transition matrix of:

Claim 6

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein code has a state transition matrix of:

Claim 7

The data channel set forth in claim 3 wherein the code is a rate 8/9 block code with a (d=0, k=11) constraint.

Claim 8

The data channel set forth in claim 4 wherein within the block code there are at most: five consecutive zeros at the start of a nine-bit code word, six consecutive zeros at the end of a nine-bit code word, seven consecutive zeros within a nine-bit code word, a single one at the start of a nine-bit code word, and two consecutive ones at the end at the end of a nine-bit code word, wherein a zero represents absence of a flux transition within a bit cell, and a one represents presence of a flux transition within a bit cell.

Claim 9

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein the block code has a state transition matrix of: ##EQU9##

Claim 10

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein the block code has a state transition matrix of: ##EQU9##

Claim 11

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein the block code has a state transition matrix of:

Claim 12

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein the block code has a state transition matrix of:

Claim 13

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein the code has a state transition matrix of:

Claim 14

A data channel implementing a time-varying maximal-transition-run code that allows up to three consecutive transitions while removing a plus-minus-plus error-event and which does not permit four or more consecutive transitions wherein the code has a state transition matrix of:

Claim 15

The data channel set forth in claim 8 wherein the code is a rate 8/9 code with constraint (d=0, G=13, I=9).

Claim 16

A magnetic recording channel including: an encoder for encoding a binary data block to be recorded into encoded data code words in accordance with a predetermined time-varying maximal-transition-run code that allows up to three consecutive magnetic flux transitions while removing a plus-minus-plus error-event and which does not allow four or more consecutive magnetic flux transitions, a write driver for converting encoded data code words into a write current, and a write element for converting the write current into a flux pattern on a magnetic storage medium moving relatively to the write element.

Claim 17

A magnetic recording channel including: an encoder for encoding a binary data block to be recorded into encoded data code words in accordance with a predetermined time-varying maximal-transition-run code that allows up to three consecutive magnetic flux transitions while removing a plus-minus-plus error-event and which does not allow four or more consecutive magnetic flux transitions, a write driver for converting encoded data code words into a write current, and a write element for converting the write current into a flux pattern on a magnetic storage medium moving relatively to the write element.

Claim 18

The magnetic recording channel set forth in claim 10 further comprising: a playback element for detecting the flux pattern on the magnetic storage medium as a minute electrical signal, an analog read channel for amplifying an equalizing to a desired spectrum the minute electrical signal to provide an amplified electrical signal, a sampler for synchronously sampling the amplified electrical signal to produce discrete data samples, a time varying detector for detecting maximum likelihood code sequences from the discrete data samples in accordance with an inverse of the predetermined time-varying maximal-transition-run code, and a decoder for decoding the sequences into a play back sequence of the binary data block.

Claim 19

The magnetic recording channel set forth in claim 10 wherein the predetermined time-varying maximal-transition-run code is a rate 8/9 block code.

Claim 20

The magnetic recording channel set forth in claim 12 wherein the rate 8/9 block code has constraint (d=0, k=11).

Claim 21

The magnetic recording channel set forth in claim 12 wherein the rate 8/9 block code has constraint (d=0, G=13, I=9).

Claim 22

The data channel set forth in claim 1 wherein the channel comprises a magnetic data storage and retrieval channel.

Claim 23

The data channel set forth in claim 2 wherein the channel comprises a magnetic data storage and retrieval channel.

Claim 24

The data channel set forth in claim 3 wherein the channel comprises a magnetic data storage and retrieval channel.

Claim 25

The data channel set forth in claim 6 wherein the channel comprises a magnetic data storage and retrieval channel.

Claim 26

The data channel set forth in claim 7 wherein the channel comprises a magnetic data storage and retrieval channel.

Claim 27

The data channel set forth in claim 8 wherein the channel comprises a magnetic data storage and retrieval channel.