Patent ID: 7072382

Claim:
A digital system for digitally modulating a datastream of digitally-represented complex values with a complex code, comprising: a first register for storing a data in-phase component value of the datastream and a corresponding data quadrature component value of the datastream; a second register for storing a code in-phase component value and a corresponding code quadrature component value; split adder circuitry for adding, for each of a plurality of bits, a digital data word including a bit of the data in-phase component value and a corresponding bit of the data quadrature component value with a digital code word including corresponding bit of the code in-phase component value arid a corresponding bit of the code quadrature component value; an output register, coupled to the adder circuitry, for storing results of the adding as a combined in-phase component value and a combined quadrature component value; and wherein the adder circuitry comprises a plurality of Gray Code adders, each Gray Code adder associated with one bit position of the respective data and code in-phase and quadrature component values, and having first and second data outputs coupled to corresponding bit positions of the output register.