Patent ID: 6898757

Claim:
A method for efficient decoding of block product code format signals, the method comprising: providing signal values r I,i and r Q,i (i=1, . . . , J; J≧1) representing J signal values expressed in a 64QAM configuration in which each of the I coordinate and the Q coordinate is associated with one of eight selected non-zero, monotonically increasing values that are approximately equal to −v1, −v2, −v3, −v4, v4, v3, v2 and v1; providing average values a1=(v1+v2+v3+v4)/4, a2=(v1+v2)/2−a1 and a3=v1−a1−a2 for the I and Q coordinate values in a first quadrant in the (I,Q) array; computing first and second triples of values defined by r xi,2 =r x,i /a 1( x=I, Q ), r xi,0 ={r xi,1 −(2· B 1x,i −1)}·( a 2/ a 3), and determining a triple of values (B 2x,i B 1x,i B 0x,i ), each value equal to 0 or 1, representing the signal value r x,i in the 64QAM configuration, according to a selected decoding process; and interpreting the triple (B 2x,i ,B 1x,i ,B 0x,i ) as a decoded sequence representing the numerical value r x,i .