Patent ID: 6917559

Claim:
A constellation mapping apparatus comprising: a memory, in which constellation values in one of four quadrants of each constellation are stored; an address generation block which receives constellation point data, bits-per-symbol information, and valid symbol information indicating whether or not the bits-per-symbol information is valid, and generates address information of the memory where the constellation values corresponding to the constellation point data are stored and quadrant information indicating a quadrant where the constellation point data are placed; a complementation logic block which complements, based on the quadrant information for the constellation point data, or does not complement the constellation values read from the memory following the address information; and a scaling block which outputs an output of the complementation logic block or a value obtained by multiplying the output of the complementation logic block by a predetermined gain obtained based on a baud rate, which indicates a speed of transmitting the bits-per-symbol information.