| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an MDCT arithmetic circuit realizing a plurality of types of arithmetic processing necessary for MDCT arithmetic operations by a smaller circuit scale than the conventional manner. <P>SOLUTION: Data stored in digital registers 11 to 18 or arithmetic units 50 to 54 are controlled by using selectors 30 to 41 according to flag registers 22 to 29 or a control signal so that MDCT arithmetic processing including butterfly arithmetic operations can be realized by a smaller circuit scale than the conventional manner. Also, the arithmetic operations for executing an addition theorem is realized by using a portion of the same circuit, so that it is possible to calculate the value of a rotary factor necessary for the butterfly arithmetic operations by the arithmetic operations. Thus, it is not necessary to preliminarily store those values in the storage device. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
