| 摘要 |
PROBLEM TO BE SOLVED: To provide an angle detection device which reduces circuit scale and is capable of performing high-speed operation.SOLUTION: An angle detection device 10 includes: a conversion section 100 for calculating a sine value (sin&thetas;) and a cosine value (cos&thetas;) corresponding to a phase angle &thetas; of an inputted baseband signal; a comparison section 110 which outputs a result of comparing magnitudes of an absolute value of the sine wave and a predetermined fixed value; a ROM 130 which outputs an inverse sine value &thetas;(in) to the inputted value; and a multiplexer 120 which outputs an absolute value of the sine value, a code of the sine value and a code of the cosine value and further outputs not-greater one of the absolute value of the sine value and the absolute value of the cosine value to the ROM on the basis of a comparison result. On the basis of the absolute value of the sine value, the code of the sine value and the code of the cosine value, the inverse sine value &thetas;(in) inputted from the ROM is converted into a phase angle &thetas;(out) within a range of -&pgr;≤&thetas;(out)≤&pgr; and outputted. By making one of input of the comparison section 110 into the predetermined fixed value, a circuit scale is reduced and high-speed operation can be performed. |
