Fast fourier transform processor
AssigneeIndustrial Technology Research Institute
InventorsJun-Xian Teng, Hsien-Yuan Hsu
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Abstract
A Fast Fourier Transform (FFT) processor is provided. It comprises a multiplexer, a first angle rotator, a second angle rotation and multiplexing unit, an adder, a twiddle factor storage, a multiplier, and a data storage. The FFT processor analyzes the input/output order of the Fast Fourier Transformation, separates the portions requiring complex computations, simplifies the hardware thereof, and adjusts the output order. It not only effectively saves the hardware area, but also reduces the computations and memory access count. Thereby, the power consumption is reduced.
Claims9
A Fast Fourier Transform (FFT) processor, comprising:
- a multiplexer for selecting an input set of N data items from a plurality of N-item sets and outputting a set of N data items, N being an M-th power of 2, M being an integer greater than or equal to 3;
- a first angle rotator for receiving N/2 data items from said N-item set, rotating said received N/2 data items for a first angle, outputting said rotated N/2 data items sequentially;
- a second angle rotation and multiplexing unit for receiving a set of N data items and said rotated N/2 data items, then either selecting said N data items within a first preset duration or selecting N/2 data items from said N data items for combining with said rotated N/2 data item within a second preset duration, rotating said resulted N data items for a second angle, outputting said rotated N data items sequentially;
- an adder for adding said N rotated data items sequentially, and outputting a sum in frequency domain of said N rotated data items;
- a twiddle factor storage for storing all the twiddle factors of an N-point FFT;
- a multiplier for multiplying said sum in frequency domain with said corresponding twiddle factor sequentially, and outputting a mean data;
- and
- a storage for receiving and storing said mean data sequentially, and outputting said N data items to said multiplexer.
Dependencies are inferred from the claim text.