Patent ID: 8621293

Claim:
A system for decision directed channel estimation, comprising: an interface configured to: receive a read-back value which is read back from storage; and receive a set of bins, wherein each bin in the set of bins has a bin range; a processor configured to: select, from the set of bins, a bin corresponding to the read-back value; adjust, based at least in part on the read-back value, the bin range of the selected bin so that the read-back value is more centered within the selected bin after adjustment; update a variance associated with the selected bin, in order to produce an updated variance, based at least in part on the read-back value and the bin range of the selected bin prior to the adjustment; and normalize the updated variance in order to produce a normalized variance associated with the selected bin; and a low-density parity-check (LDPC) decoder which is configured to input the normalized variance associated with the selected bin.