Data pattern dependent amplitude adjustment
Data is processed by receiving data having a value. The amplitude of the received data is adjusted using the processor based at least in part on the value of the received data to obtain modified data.
1. A method for processing data, comprising:
receiving a digital signal associated with data stored in a first storage location, wherein the digital signal includes noise associated with a second storage location;
processing the digital signal using a detector to obtain a decision;
selecting a gain from a plurality of gain values based at least in part on the decision, wherein in the event the decision is associated with low-frequency data, an amplifying gain value is selected and in the event the decision is associated with high-frequency data, an attenuating gain value is selected; and
using a processor to remove the noise associated with the second storage location from the digital signal based at least in part on the decision, including by:
in the event the decision is associated with low-frequency data, amplifying the digital signal using the amplifying gain value; and
in the event the decision is associated with high-frequency data, attenuating the digital signal using the attenuating gain value.
2. The method of claim 1 , wherein the digital signal has been processed by one or more of the following: a continuous timing filter (CTF), an analog to digital converter (ADC), an equalized filter, or a finite impulse response (FIR) filter.
3. The method of claim 1 , wherein the digital signal includes data that has been stored in Flash storage or magnetic disk storage.
4. The method of claim 1 , wherein the detector includes at least one of the following: a threshold slicer, a decision feed-back equalizer (DFE), a maximum-likelihood (ML) detector, or a maximum a priori (MAP) detector.
5. The method of claim 1 , wherein:
selecting further includes in the event the decision is associated with medium-frequency data, selecting a third gain value which is greater than the attenuating gain value and less than the amplifying gain value; and
using the processor to remove noise further includes in the event the decision is associated with medium-frequency data, adjusting the digital signal using the third gain value.
6. The method of claim 1 , wherein:
the amplifying gain value is adjustable; and
the method further includes:
determining an ideal signal based at least in part on the decision;
determining an error corresponding to a difference between the ideal signal and the digital signal; and
adjusting the amplifying gain value based at least in part on the error.
7. The method of claim 1 , wherein:
the attenuating gain value is adjustable; and
the method further includes:
determining an ideal signal based at least in part on the decision;
determining an error corresponding to a difference between the ideal signal and the digital signal; and
adjusting the attenuating gain value based at least in part on the error.
8. A system for processing data, comprising:
an interface configured to receive a digital signal associated with data stored in a first storage location, wherein the digital signal includes noise associated with a second storage location;
a detector configured to process the digital signal to obtain a decision;
a selector configured to select a gain from a plurality of gain values based at least in part on the decision, wherein in the event the decision is associated with low-frequency data, an amplifying gain value is selected and in the event the decision is associated with high-frequency data, an attenuating gain value is selected; and
a processor configured to remove the noise associated with the second storage location from the digital signal based at least in part on the decision;
in the event the decision is associated with low-frequency data, amplifying the digital signal using the amplifying gain value; and
in the event the decision is associated with high-frequency data, attenuating the digital signal using the attenuating gain value.
9. The system of claim 8 , wherein the digital signal has been processed by one or more of the following: a continuous timing filter (CTF), an analog to digital converter (ADC), an equalized filter, or a finite impulse response (FIR) filter.
10. The system of claim 8 , wherein the digital signal includes data that has been stored in Flash storage or magnetic disk storage.
11. The system of claim 8 , wherein the detector includes at least one of the following: a threshold slicer, a decision feed-back equalizer (DFE), a maximum-likelihood (ML) detector, or a maximum a priori (MAP) detector.
12. The system of claim 8 , wherein:
the selector is further configured to: in the event the decision is associated with medium-frequency data, select a third gain value which is greater than the attenuating gain value and less than the amplifying gain value; and
the processor is further configured to remove noise by: in the event the decision is associated with medium-frequency data, adjust the digital signal using the third gain value.
13. The system of claim 8 , wherein:
the amplifying gain value is adjustable; and
the system further includes:
a processor configured to:
determine an ideal signal based at least in part on the decision; and
determine an error corresponding to a difference between the ideal signal and the digital signal; and
a gain adjustor configured to adjust the amplifying gain value based at least in part on the error.
14. The system of claim 8 , wherein:
the attenuating gain value is adjustable; and
the system further includes:
a processor configured to:
determine an ideal signal based at least in part on the decision; and
determine an error corresponding to a difference between the ideal signal and the digital signal; and
a gain adjustor configured to adjust the attenuating gain value based at least in part on the error.
15. A computer program product for processing data, the computer program product being embodied in a non-transitory computer readable storage medium and comprising computer instructions for:
receiving a digital signal associated with data stored in a first storage location, wherein the digital signal includes noise associated with a second storage location;
processing the digital signal using a detector to obtain a decision;
selecting a gain from a plurality of gain values based at least in part on the decision, wherein in the event the decision is associated with low-frequency data, an amplifying gain value is selected and in the event the decision is associated with high-frequency data, an attenuating gain value is selected; and
removing the noise associated with the second storage location from the digital signal based at least in part on the decision, including by:
in the event the decision is associated with low-frequency data, amplifying the digital signal using the amplifying gain value; and
in the event the decision is associated with high-frequency data, attenuating the digital signal using the attenuating gain value.
16. The computer program product of claim 15 , wherein:
the computer instructions for selecting further include computer instructions for: in the event the decision is associated with medium-frequency data, selecting a third gain value which is greater than the attenuating gain value and less than the amplifying gain value; and
the computer instructions for removing noise further include computer instructions for: in the event the decision is associated with medium-frequency data, adjusting the digital signal using the third gain value.
17. The computer program product of claim 15 , wherein:
the amplifying gain value is adjustable; and
the computer program product further includes computer instructions for:
determining an ideal signal based at least in part on the decision;
determining an error corresponding to a difference between the ideal signal and the digital signal; and
adjusting the amplifying gain value based at least in part on the error.
18. The computer program product of claim 15 , wherein:
the attenuating gain value is adjustable; and
the computer program product further includes computer instructions for:
determining an ideal signal based at least in part on the decision;
determining an error corresponding to a difference between the ideal signal and the digital signal; and
adjusting the attenuating gain value based at least in part on the error.