A 64‐points switched‐capacitor discrete fourier transform circuit for high‐speed inverse discrete fourier transform circuit
Akio Ogihara, Shojiro Yoneda · Electronics and Communications in Japan (Part III Fundamental Electronic Science) · 1990
Abstract The Discrete Fourier Transform (DFT) and Inverse Discrete Fourier Transform (IDFT) are used for solution of various problems in communications, signal processing and many fields of science. This paper proposes a new method to execute DFT which enables one to realize a high‐speed IDFT circuit with small circuit configuration. In this method, multiplying the DFT equation by the exponential term of the IDFT equation beforehand, IDFT processing is carried out only by addition without increasing the complexity of DFT processing. Using this method, a 64‐points DFT‐IDFT circuit is made on an experimental basis by the switched‐capacitor (SC) technique. In addition, the SC DFT‐IDFT circuit is applied to the recognition of Japanese vowels, and its validity is verified experimentally.