# US 8,570,879 B2 · Obtaining parameters for minimizing an error event probability

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,570,879 B2
- Document ID: US8570879B2
- Status: Granted
- Kind: B2
- Application number: 12/962,226
- Filed: 2010-12-07
- Published: 2011-03-31
- Granted: 2013-10-29
- Earliest claimed: 2008-04-18
- Assignees: SK hynix memory solutions inc.
- Applicants: Marcus Marrow; Jason Bellorado
- Inventors: Marcus Marrow; Jason Bellorado
- Web page: https://patentgrep.com/patent/US8570879B2

## CPC

- H04L 43/00: Arrangements for monitoring or testing data switching networks
- H04L 1/0019: {in which mode-switching is based on a statistical approach}
- H04L 1/0054: {Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms}
- H04L 1/24: Testing correct operation
- H04L 25/03038: {with a non-recursive structure (H04L25/03031 takes precedence)}
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)

## Abstract

A set of one or more receiver parameters is adjusted. It is determined whether to adjust the set of receiver parameters. In the event it is determined to adjust the set of receiver parameters, a new set of values is generated for the set of receiver parameters using a cost function (where the cost function does not assume a noise signal in a receive signal to have a particular statistical distribution) and the set of receiver parameters is changed to have the new set of values.

## Claims

### Claim 1

A method for adjusting a set of one or more receiver parameters, comprising:
determining whether to adjust the set of one or more receiver parameters, including by:
obtaining, from a Viterbi detector, a metric having a sign and a magnitude, wherein an error is indicated by the Viterbi detector if the sign of the metric is a first sign value and no error is indicated by the Viterbi detector if the sign of the metric is a second sign value;
determining to adjust the set of one or more receiver parameters if the sign of the metric is the first sign value;
determining to adjust the set of one or more receiver parameters if the sign of the metric is the second sign value and the magnitude of the metric is less than a predefined magnitude; and
determining not to adjust the set of one or more receiver parameters if the sign of the metric is the second sign value and the magnitude of the metric is greater than the predefined magnitude; and
if it is determined to adjust the set of one or more receiver parameters:
using a processor to generate a new set of values for the set of one or more receiver parameters using a cost function, wherein the cost function does not assume a noise signal in a receive signal to have a particular statistical distribution; and
using the processor to change the set of one or more receiver parameters to have the new set of values.

### Claim 2 (depends on 1)

The method of claim 1, wherein the set of one or more receiver parameters are associated with a read channel of a disk storage system.

### Claim 3 (depends on 1)

The method of claim 1, wherein changing the set of one or more receiver parameters includes adjusting one or more settings of a disk storage system.

### Claim 4 (depends on 1)

The method of claim 1, wherein the new set of values corresponds to a subset of the set of one or more receiver parameters.

### Claim 5 (depends on 1)

The method of claim 1, wherein the set of one or more receiver parameters includes at least one of the following: a parameter associated with an equalizer, a parameter associated with a pattern dependent finite impulse response (FIR) filter, a parameter associated with the Viterbi Detector.

### Claim 6 (depends on 1)

The method of claim 1 further comprising determining the cost function using a function of Ũ(x), wherein Ũ(x)=−α for x<−α, Ũ(x)=x for |x|<α, and Ũ(x)=α if x>α where x is an input to Ũ(x) and is a real-number and α is a parameter of Ũ(x) and is a positive real-number.

### Claim 7 (depends on 1)

The method of claim 1 further comprising determining the cost function using a stochastic gradient descent.

### Claim 8

A system for adjusting a set of one or more receiver parameters, comprising:
a controller configured to determine whether to adjust the set of one or more receiver parameters, including by:
obtaining, from a Viterbi detector, a metric having a sign and a magnitude, wherein an error is indicated by the Viterbi detector if the sign of the metric is a first sign value and no error is indicated by the Viterbi detector if the sign of the metric is a second sign value;
determining to adjust the set of one or more receiver parameters if the sign of the metric is the first sign value;
determining to adjust the set of one or more receiver parameters if the sign of the metric is the second sign value and the magnitude of the metric is less than a predefined magnitude; and
determining not to adjust the set of one or more receiver parameters if the sign of the metric is the second sign value and the magnitude of the metric is greater than the predefined magnitude;
a parameter generator configured to generate a new set of values for the set of one or more receiver parameters using a cost function if it is determined to adjust the set of one or more receiver parameters, wherein the cost function does not assume a noise signal in a receive signal to have a particular statistical distribution; and
an interface configured to change the set of one or more receiver parameters to have the new set of values if it is determined to adjust the set of one or more receiver parameters.

### Claim 9 (depends on 8)

The system of claim 8, wherein the new set of values corresponds to a subset of the set of one or more receiver parameters.

### Claim 10 (depends on 8)

The system of claim 8, wherein the set of one or more receiver parameters includes at least one of the following: a parameter associated with an equalizer, a parameter associated with a pattern dependent finite impulse response (FIR) filter, a parameter associated with the Viterbi Detector.

### Claim 11 (depends on 8)

The system of claim 8, wherein the controller is further configured to determine the cost function using a function of Ũ(x), wherein Ũ(x)=−α for x<−α, Ũ(x)=x for |x|<α, and Ũ(x)=α if x>α where x is an input to Ũ(x) and is a real-number and α is a parameter of Ũ(x) and is a positive real-number.

### Claim 12 (depends on 8)

The system of claim 8, wherein the controller is further configured to determine the cost function using a stochastic gradient descent.

### Claim 13

A computer program product for adjusting a set of one or more receiver parameters, the computer program product being embodied in a non-transitory computer readable storage medium and comprising computer instructions for:
determining whether to adjust the set of one or more receiver parameters, including by:
obtaining, from a Viterbi detector, a metric having a sign and a magnitude, wherein an error is indicated by the Viterbi detector if the sign of the metric is a first sign value and no error is indicated by the Viterbi detector if the sign of the metric is a second sign value;
determining to adjust the set of one or more receiver parameters if the sign of the metric is the first sign value;
determining to adjust the set of one or more receiver parameters if the sign of the metric is the second sign value and the magnitude of the metric is less than a predefined magnitude; and
determining not to adjust the set of one or more receiver parameters if the sign of the metric is the second sign value and the magnitude of the metric is greater than the predefined magnitude; and
if it is determined to adjust the set of one or more receiver parameters:
generating a new set of values for the set of one or more receiver parameters using a cost function, wherein the cost function does not assume a noise signal in a receive signal to have a particular statistical distribution; and
changing the set of one or more receiver parameters to have the new set of values.

### Claim 14 (depends on 13)

The computer program product of claim 13, wherein the set of one or more receiver parameters are associated with a read channel of a disk storage system.

### Claim 15 (depends on 13)

The computer program product of claim 13, wherein the computer instructions for changing the set of one or more receiver parameters include computer instructions for adjusting one or more settings of a disk storage system.

### Claim 16 (depends on 13)

The computer program product of claim 13, wherein the new set of values corresponds to a subset of the set of one or more receiver parameters.

### Claim 17 (depends on 13)

The computer program product of claim 13, wherein the set of one or more receiver parameters includes at least one of the following: a parameter associated with an equalizer, a parameter associated with a pattern dependent finite impulse response (FIR) filter, a parameter associated with the Viterbi Detector.

### Claim 18 (depends on 13)

The computer program product of claim 13 further comprising computer instructions for determining the cost function using a function of Ũ(x), wherein Ũ(x)=−α for x<−α, Ũ(x)=x for |x|<α, and Ũ(x)=α if x>α where x is an input to Ũ(x) and is a real-number and α is a parameter of Ũ(x) and is a positive real-number.

### Claim 19 (depends on 13)

The computer program product of claim 13 further comprising computer instructions for determining the cost function using a stochastic gradient descent.