| 摘要 |
<p>PURPOSE:To provide a device capable of furthermore reducing hardware scale and cost in respect of a device for executing the fast Fourier transformation(FFT) of input data for many points in parallel. CONSTITUTION:This FFT device has a prestage part 12 constituted of arranging the plural number of FFT circuits 10 (the power of cardinal number 2) each of which consists of a serial type of a cardinal number '2' and a post stage part 16 provided with a pair of parallel extended FFT circuits 14 connected so that both of two wide outputs obtained from the circuits 10 are respectively supplied to both the circuits 14, and each of circuits 14 includes plural butterfly operation circuits 18 arranged as a matrix and supplied with outputs from the circuits 10 to the heads of respective rows, twist coefficient multiplying circuits 20 incorporated in respective circuits 18 and twist coefficient supplying circuits 22 each of which supplies a series of twist coefficients determined by the matrix position of the corresponding circuit 18, the number of pieces of data applied to respective circuits 10 and the number of circuits 10 to its corresponding circuit 20.</p> |
