Patent ID: 6421394
Filing Date: 2002-07-16
Classification: H04L

Abstract:
A computer method of point slicing in digital communication systems employing Quadrature Amplitude Modulation (QAM) having a defined number of bits per symbol, wherein said number of bits per symbol defines a QAM hard point constellation, the method comprising the steps of:providing an infinite lattice, wherein said infinite lattice is spatially defined by a coordinate system having an origin located at the intersection of two or more axes, said infinite lattice comprising at least one subset of said QAM constellation hard points; receiving at least one subset of soft points, said soft points spatially mapping into said infinite lattice; defining at least one valid constellation boundary, said valid constellation boundary defining a set of valid constellation hard points, wherein said set of valid constellation hard points is a subset of said QAM hard point constellation, said valid constellation boundary having a constellation origin; determining a closest valid constellation hard point for each soft point in said subsets of soft points; and reporting said closest valid constellation hard point.