Systems and methods for efficient parameter modification
View Patent ↗Various embodiments of the present invention provide systems and methods for data processing.
1. A data processing system, the data processing system comprising:
a data detector circuit operable to apply a data detection algorithm to a first data set guided by a decoded output to yield a detected output;
a data decoder circuit operable to apply a data decode algorithm to a second data set to yield the decoded output, wherein the second data set is derived from the first data set;
a reliability monitor circuit operable to calculate an error rate based at least in part on an output selected from a group consisting of: a third data set derived from the decoded output, and the first data set;
a parameter modification control circuit operable to:
select a first value for a parameter and to store a first instance of the error rate corresponding to the first value;
select a second value for the parameter and to store a second instance of error count corresponding to the second value, wherein selecting the second value includes: determining a search direction based at least in part on the first value; and using the search direction and a step size to calculate the second value; and
select one of the first value and the second value based at least in part on a comparison of the first instance of the error rate and the second instance of the error rate.
2. The data processing system of claim 1 , wherein calculating the error rate includes comparing the third data set against a known data set.
3. The data processing system of claim 2 , wherein the third data set is a set of hard decision outputs.
4. The data processing system of claim 1 , wherein the data detection algorithm is selected from a group consisting of: a maximum a posteriori data detection algorithm and a Viterbi detection algorithm.
5. The data processing system of claim 3 , wherein the data decode algorithm is a low density parity check algorithm.
6. The data processing system of claim 1 , wherein the output is the third data set derived from the decoded output, and wherein the reliability monitor circuit comprises:
a comparator circuit operable to compare instances of the third data set against a known data set; and
a counter circuit operable to increment when an instance of the third data set is not equal to a corresponding instance of the known data set to yield the error rate.
7. The data processing circuit of claim 1 , wherein the output is the first data set, wherein the first data set includes soft data, and wherein the reliability monitor circuit comprises:
a comparator circuit operable to compare instances of the soft data against a threshold value; and
a counter circuit operable to increment when an instance of the soft data is less than the threshold value to yield the error rate.
8. The data processing system of claim 7 , wherein the threshold value is programmable.
9. The data processing system of claim 1 , wherein the steps size is programmable.
10. The data processing circuit of claim 1 , wherein the data processing system is implemented as part of a device selected from a group consisting of: a storage device and a receiving device.
11. The data processing system of claim 1 , wherein the data processing system is implemented as part of an integrated circuit.
12. A method for data processing, the method comprising:
performing a data detection algorithm using a data detector circuit on a first data set to yield a detected output;
performing a data decode algorithm using a data decoder circuit on a second data set derived from the first data set to yield a decoded output;
calculating an error rate based at least in part on an output selected from a group consisting of: a third data set derived from the decoded output, and the first data set;
selecting a first value for a parameter and storing a first instance of the error rate corresponding to the first value;
selecting a second value for the parameter and storing a second instance of error count corresponding to the second value, wherein selecting the second value includes: determining a search direction based at least in part on the first value; and using the search direction and a step size to calculate the second value; and
selecting one of the first value and the second value based at least in part on a comparison of the first instance of the error rate and the second instance of the error rate.
13. The method of claim 12 , wherein the output is the third data set derived from the decoded output, and wherein calculating the error rate comprises:
comparing instances of the third data set against a known data set; and
counting the number of instances of the third data set that are not equal to a corresponding instance of the known data set to yield the error rate.
14. The method of claim 12 , wherein the output is the first data set, wherein the first data set includes soft data, and wherein calculating the error rate comprises:
comparing instances of the soft data against a threshold value; and
counting the number of instances of the soft data that are less than the threshold value to yield the error rate.
15. The method of claim 14 , wherein the threshold value is programmable.
16. The method of claim 12 , wherein the third data set is a set of hard decision outputs.
17. The method of claim 12 , wherein the steps size is programmable.
18. A storage device, the storage device comprising:
a storage medium;
a head assembly disposed in relation to the storage medium and operable to provide a sensed signal corresponding to information on the storage medium;
a read channel circuit including:
an analog to digital converter circuit operable to sample an analog signal derived from the sensed signal to yield a series of digital samples;
an equalizer circuit operable to equalize the digital samples to yield a first data set;
a data detector circuit operable to apply a data detection algorithm to the first data set;
a data decoder circuit operable to apply a data decode algorithm to a second data set to yield a decoded output, wherein the second data set is derived from the first data set;
a reliability monitor circuit operable to calculate an error rate based at least in part on an output selected from a group consisting of: a third data set derived from the decoded output, and the first data set;
a parameter modification control circuit operable to:
select a first value for a parameter and to store a first instance of the error rate corresponding to the first value;
select a second value for the parameter and to store a second instance of error count corresponding to the second value, wherein selecting the second value includes: determining a search direction based at least in part on the first value; and using the search direction and a step size to calculate the second value; and
select one of the first value and the second value based at least in part on a comparison of the first instance of the error rate and the second instance of the error rate.
19. The storage device of claim 18 , wherein the output is the third data set derived from the decoded output, and wherein the reliability monitor circuit comprises:
a comparator circuit operable to compare instances of the third data set against a known data set; and
a counter circuit operable to increment when an instance of the third data set is not equal to a corresponding instance of the known data set to yield the error rate.
20. The storage device of claim 18 , wherein the output is the first data set, wherein the first data set includes soft data, and wherein the reliability monitor circuit comprises:
a comparator circuit operable to compare instances of the soft data against a threshold value; and
a counter circuit operable to increment when an instance of the soft data is less than the threshold value to yield the error rate.