SIGNAL GENERATOR

PROBLEM TO BE SOLVED: To generate and output a sine wave signal and a cosine wave signal as full angle data with a required angular resolution without the need for increasing a capacity of a ROM or a RAM even when a finer output resolution of the sine wave and the cosine wave is a requirement without the need for full angle data of the sine wave and the cosine wave in a form of a table. SOLUTION: An output angle θ is divided into two angular components, in which the one angle θ1 is selected to be an integral multiple of the angle θT and the other angle θ2 is selected to be an angle less than the angle θT, by respectively referring to a sine wave table 1 and a cosine wave table 2 that are tabulated in the unit of a multiple of an angle θT below an angular resolution of an output requirement and a sine wave table 3 and a cosine wave table 4 that have an angular resolution being an output requirement in the unit of an angle equal to and less than the θT. Then, the sinθ1 is multiplied (8) by cosθ2, the cosθ1 is multiplied (8) by sinθ2, an adder 9 sums the respective products, the sum is normalized 10 with the amplitude of an output signal, a latch 11 latches the normalized signal for each sampling clock, a D/A converter 18 applies D/A conversion to the latched data and provides an output of a sine wave.