Patent ID: 8705662

Claim:
A soft decision method for determining a soft decision coordinate associated with a constellation, the soft decision coordinate comprising a first soft decision sub-coordinate and a second soft decision sub-coordinate, the soft decision method comprising: a signal retriever, for receiving an input signal comprising a coordinate value; defining a first coordinate range on a coordinate axis in the constellation, the first coordinate range having a first limit and a second limit; obtaining the first soft decision sub-coordinate according to the first coordinate range; defining a second coordinate range on the coordinate axis in the constellation, the second coordinate range having a third limit and a fourth limit; and obtaining the second soft decision sub-coordinate according to the second coordinate range, wherein, the first limit and the third limit do not simultaneously equal to the second limit and the fourth limit, and wherein the coordinate value has a fifth limit and a sixth limit, the first limit and the second limit are generated from multiplying a first coefficient by the fifth limit and the sixth limit respectively, and the third limit and the fourth limit are generated from multiplying a second coefficient by the fifth limit and the sixth limit respectively, wherein the second coefficient and the first coefficient are not equal.