Nyquist constrained digital finite impulse response filter

A method for filtering a signal, comprising:

• providing a digital finite impulse response filter having a plurality of tap weight inputs;
• providing a tap weight controller connected to the digital finite impulse response filter;
• using the tap weight controller, calculating a Nyquist response of the digital finite impulse response filter based on at least some of the plurality of tap weight inputs;
• determining whether a magnitude of the Nyquist response of the digital finite impulse response filter is outside of a Nyquist constraint range;
• and
• if the magnitude of the Nyquist response of the digital finite impulse response filter is outside of the Nyquist constraint range, calculating a tap weight offset and applying the tap weight offset to the at least some of the plurality of tap weight inputs.

A storage system comprising:

• a storage medium maintaining a data set;
• a read/write head assembly operable to sense the data set on the storage medium and to provide an analog output corresponding to the data set;
• an amplifier circuit operable to amplify the analog output to yield an amplified analog output;
• an analog to digital converter operable to sample the amplified analog output to yield a digital signal;
• a digital finite impulse response filter operable to filter the digital signal;
• and
• a tap weight controller operable to provide a tap weight to each of a plurality of tap weight inputs on the digital finite impulse response filter, wherein the tap weight controller is operable further operable to adjust the tap weights for each of a subset of the plurality of tap weight inputs such that a magnitude of a Nyquist response of the digital finite impulse response filter remains within a Nyquist constraint range.