Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
78 words
A method for coding input strings for a binary (1 + D) or (1 + D)² partial response channel that requires at least two consecutive signals of one state in order to record or transmit data to a receiving device, which includes the step of encoding an input string into a binary code string according to an EMM constraint in which all one-state signals are in pairs, and signals of an opposite state need not be in pairs.
Claim 2
Independent Claim
78 words
A method for coding input strings for a binary (1 + D) or (1 + D)² partial response channel that requires at least two consecutive signals of one state in order to record or transmit data to a receiving device, which includes the step of encoding an input string into a binary code string according to an EMM constraint in which all one-state signals are in pairs, and signals of an opposite state need not be in pairs.
Claim 3
Dependent Claim
20 words
A method as claimed in claim 1, wherein the one-state signals are in runs of one or more contiguous pairs.
Claim 4
Independent Claim
43 words
A method as claimed in either preceding claim, wherein the maximum run of consecutive one-state state signals is limited to eliminate EMM sequences that produce worst-case performance by improving timing and gain control by limiting the maximum run of consecutive channel output values.
Claim 5
Dependent Claim
18 words
A method as claimed in claim 3, wherein the maximum run of one-state signals is six consecutive pairs.
Claim 6
Independent Claim
45 words
A method as claimed in any of claims 1 to 3, including the further steps of: supplying to the channel the binary code string satisfying the EMM constraint; generating a channel output sequence; and detecting a most probable EMM sequence from the channel output sequence.
Claim 7
Dependent Claim
43 words
A method as claimed in claim 5, including the further step of decoding the most probable EMM sequence for generating EMM code output data and wherein there are no more than eight consecutive signals of the opposite state in the channel output sequence.
Claim 8
Independent Claim
42 words
A method as claimed in any preceding claim for a (1 + D) partial response channel, wherein a maximum likelihood algorithm based upon a three-state trellis structure incorporating a difference metric calculation is used to obviate the need for re-normalisation of metrics.
Claim 9
Independent Claim
45 words
A method as claimed in any of claims 1 to 6 for a (1 + D)² partial response channel, wherein a maximum likelihood algorithm based upon a five-state trellis structure incorporating a difference metric calculation is used to obviate the need for re-normalisation of metrics.
Claim 10
Independent Claim
28 words
A method as claimed in any preceding claim, wherein the binary code has an un-normalised coding gain of at least 3 dB with respect to the uncoded channel.
Claim 11
Independent Claim
18 words
A method as claimed in any preceding claim, wherein the binary code has a coding rate of 2/3.