| 摘要 |
PROBLEM TO BE SOLVED: To digitally generate a sine wave with a small ROM capacity. SOLUTION: This sine wave generation circuit is provided with: a coefficient ROM 1 which stores coefficients expressing an angular frequency according to a desired frequency and a sampling frequency and two kinds of coefficients to one desired frequency; an accumulation operation part 2 which obtains the angular frequency at each sample point by sequentially adding coefficient values stored in the coefficient ROM 1 at each sampling frequency using one coefficient while an accumulated value does not exceed a threshold and using the other coefficient when the accumulated value exceeds the threshold; and a CORDIC 3 which generates a sine wave signal with the desired frequency by calculating an amplitude of the sine wave corresponding to the angular frequency at each sample point obtained by the accumulation operation part 2 and generates the sine wave signal with the desired frequency by a digital operation only by the two kinds of coefficients. COPYRIGHT: (C)2008,JPO&INPIT
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