Apparatus and method for carrying out a complex multiplication for special values amounts

摘要

The appts. carries out a complex multiplication using one adder, one subtractor, two negation units and one output unit, with the negation units and output unit controlled by a second multiplier. The complex multipliers consist of an adder (14) and a subtractor. The adder creates a sum and the subtractor (15) creates a difference of the real part and the imaginary part of the first multiplier. A first negation unit (16) performs negation of the sum according to the real part of the second multiplier. A second negation unit (17) performs random negation of the difference depending on an imaginary part of the second multiplier. A result selector (18,19) selects the result from the two negation units either as the imaginary part and real part or as real part and imaginary part of a complex multiplication result. The selection is made dependent on the real part and imaginary part of the second multiplier. The output signals of the two negations units (16,17) are cross-fed as the inputs of the two multipliers (18,19). EX-OR gates (20) create a selection control signal (SA) It corresponds to the XOR connection of the real part and the imaginary part of the second multiplier, where the selection control signals control the result selection unit (18,19).