Systems and methods for burst demodulation

1. A data processing circuit comprising:

a burst integration circuit operable to calculate burst integration results for a servo data burst field;

a comparison circuit operable to determine whether an absolute value of the burst integration results falls outside a window; and

an error indicating circuit operable to indicate that a media flaw has been detected when the absolute value of the burst integration results fall outside the window.

2. The data processing circuit of claim 1 , wherein the burst integration circuit is operable to calculate the burst integration results for every half-cycle of data from the servo data burst field.

3. The data processing circuit of claim 1 , wherein the servo data burst field comprises burst information read from a servo wedge on a magnetic storage disk.

4. The data processing circuit of claim 1 , wherein the burst integration circuit is operable to perform a dot product operation on a data input derived from the servo data burst field and at least one discrete Fourier transform coefficient.

5. The data processing circuit of claim 1 , wherein the burst integration circuit is operable to perform a match filter operation on a data input derived from the servo data burst field with at least one discrete Fourier transform coefficient.

6. The data processing circuit of claim 1 , further comprising an accumulator operable to sum the burst integration results from the burst integration circuit over a particular burst and to produce a position error signal based on a value in the accumulator.

7. The data processing circuit of claim 1 , further comprising an ideal estimation circuit operable to calculate an estimated ideal result based on absolute values of the burst integration results, wherein the estimated ideal results comprises a value selected from a group consisting of: a mean and a median.

8. The data processing circuit of claim 1 , further comprising a plurality of registers operable to store each half-cycle burst integration result from the burst integration circuit.

9. The data processing circuit of claim 8 , further comprising a correction circuit operable to replace each half-cycle burst integration result in the plurality of registers, for which the absolute value of the burst integration result falls outside the window, with an ideal estimated half-cycle burst integration result.

10. The data processing circuit of claim 9 , wherein the correction circuit is further operable to calculate a corrected position error signal based on the half-cycle burst integration results in the plurality of registers.

11. The data processing circuit of claim 1 , wherein the circuit is implemented as an integrated circuit.

12. The data processing circuit of claim 1 , wherein the data processing circuit is implemented as part of a data storage device.

13. A method for demodulating a servo data burst field, comprising:

calculating a burst integration result for each half-cycle of the burst field;

accumulating the burst integration results for each half-cycle of the burst field to produce a position error signal;

determining whether an absolute value of the burst integration result for each half-cycle of the burst field is outside a window; and

flagging a media flaw when an absolute value of the burst integration result for any half-cycle of the burst field is outside the window.

14. The method of claim 13 , further comprising calculating an estimated ideal result for the absolute values of the burst integration result for each half-cycle of the burst field as a function of the absolute values of the burst integration result for each half-cycle of the burst field, wherein the function is selected from a group consisting of: a mean and a median.

15. The method of claim 14 , further comprising calculating the window based on the estimated ideal result and a threshold, wherein the threshold is expressed as a percentage of the estimated ideal result.

16. The method of claim 15 , wherein a lower boundary of the window is calculated as the threshold multiplied by the estimated ideal result, and an upper boundary of the window is calculated as two minus the threshold, multiplied by the estimated ideal result.

17. The method of claim 13 , further comprising producing a corrected position error signal by replacing any of the burst integration results for each half-cycle of the burst field for which the absolute value falls outside the window, with an estimated ideal result for the absolute value of each half-cycle of the burst integration result, and re-accumulating.

18. The method of claim 13 , further comprising disabling the determining and the flagging for the burst field if an estimated ideal result for the absolute value of each half-cycle of the burst integration result is below a threshold.

19. The method of claim 13 , wherein calculating a burst integration result for each half-cycle of the burst field comprises finding a dot product of data samples for the half-cycle and at least one discrete Fourier transform coefficient.

20. A 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 a data set on the storage medium; and

a read channel circuit including a burst demodulator, comprising:

a burst integration circuit operable to calculate burst integration results for a servo data burst field in the data set;

a comparison circuit operable to determine whether an absolute value of the burst integration results falls outside a window; and

an error indicating circuit operable to indicate that a media flaw has been detected when the absolute value of the burst integration results fall outside the window.