LDPC Decoder With Targeted Symbol Flipping

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 analog to digital converter operable to sample a continuous signal to yield a digital output;
• and
• a non-binary low density parity check data decoder operable to decode data in the digital output, comprising:
• a variable node processor operable to update variable node symbol values according to a plurality of elements in a non-binary Galois Field;
• a check node processor connected to the variable node processor and operable to perform parity check calculations;
• and
• a controller operable to perform symbol flipping and to control decoding iterations in the variable node processor and the check node processor.