Offset value determination in a check node processing unit for message-passing decoding of non-binary codes

Abstract

Embodiments of the invention provide an elementary check node processing unit () implemented in a check node processing unit of a non-binary error correcting code decoder, the elementary check node processing unit () being linked to a variable node processing unit () and being configured to receive a first message and a second message, each message comprising at least two components. The elementary check node processing unit () comprises a calculation unit () which determines two or more auxiliary components from the components comprised in the first message and from the components comprised in the second message, an auxiliary component comprising an auxiliary reliability metrics. The calculation unit () also determines, in association with each of the two or more auxiliary components, decoding performance values. The elementary check node processing unit () also comprises a selection unit () which selects, among the two or more auxiliary components, the auxiliary component that is associated with the optimal decoding performance values and determines an offset value from the auxiliary reliability metrics comprised in the selected auxiliary component. The elementary check node processing unit () then transmits the offset value and a selected set of auxiliary components among the two or more auxiliary components to the variable node processing unit ().