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Abstrak :
The DFT: An Owner's Manual for the Discrete Fourier Transform explores both the practical and theoretical aspects of the DFT, one of the most widely used tools in science, engineering, and computational mathematics. Designed to be accessible to an audience with diverse interests and mathematical backgrounds, the book is written in an informal style and is supported by many examples, figures, and problems. Conceived as an "owner's" manual, this comprehensive book covers such topics as the history of the DFT, derivations and properties of the DFT, comprehensive error analysis, issues concerning the implementation of the DFT in one and several dimensions, symmetric DFTs, a sample of DFT applications, and an overview of the FFT.

Abstrak :
One of the best known fast computational algorithms is the fast Fourier transform method. Its efficiency is based mainly on the special structure of the discrete Fourier transform matrix. Recently, many other algorithms of this type were discovered, and the theory of structured matrices emerged. This volume contains 22 survey and research papers devoted to a variety of theoretical and practical aspects of the design of fast algorithms for structured matrices and related issues. Included are several papers containing various affirmative and negative results in this direction. The theory of rational interpolation is one of the excellent sources providing intuition and methods to design fast algorithms. The volume contains several computational and theoretical papers on the topic. There are several papers on new applications of structured matrices, e.g., to the design of fast decoding algorithms, computing state-space realizations, relations to Lie algebras, unconstrained optimization, solving matrix equations, etc.

Abstrak :
The most comprehensive treatment of FFTs to date. Van Loan captures the interplay between mathematics and the design of effective numerical algorithms--a critical connection as more advanced machines become available. A stylized Matlab notation, which is familiar to those engaged in high-performance computing, is used. The Fast Fourier Transform (FFT) family of algorithms has revolutionized many areas of scientific computation. The FFT is one of the most widely used algorithms in science and engineering, with applications in almost every discipline. This volume is essential for professionals interested in linear algebra as well as those working with numerical methods. The FFT is also a great vehicle for teaching key aspects of scientific computing.

Abstrak :
Intended for students and researchers, this text employs basic techniques of univariate and multivariate statistics for the analysis of time series and signals. It provides a broad collection of theorems, placing the techniques on firm theoretical ground. The techniques, which are illustrated by data analyses, are discussed in both a heuristic and a formal manner, making the book useful for both the applied and the theoretical worker. An extensive set of original exercises is included.

Abstrak :
This work addresses this problem in the short-time Fourier transform (STFT) domain. We divide the general problem into five basic categories depending on the number of microphones being used and whether the interframe or interband correlation is considered. The first category deals with the single-channel problem where STFT coefficients at different frames and frequency bands are assumed to be independent. The second category also concerns the single-channel problem. The difference is that now the interframe correlation is taken into account and a filter is applied in each subband instead of just a gain. The third and fourth classes discuss the problem of multichannel noise reduction in the STFT domain with and without interframe correlation, respectively. In the last category, consider the interband correlation in the design of the noise reduction filters. Illustrate the basic principle for the single-channel case as an example, while this concept can be generalized to other scenarios. In all categories, propose different optimization cost functions from which derive the optimal filters and we also define the performance measures that help analyzing them.

Abstrak :
ABSTRAK
Untuk menyederhanakan solusi dari suatu masalah komputasi selalu digunakan apa yang disebut dengan teknik analisa transformasi. Salah satu contoh dari teknik analisa ini adalah transformasi Fourier. Transformasi Fourier dari sebuah gelombang diperlukan untuk memisah gelombang tersebut menjadi sejumlah gelombang sinusoidal dengan frekwensi yang berbeda.
Dengan dikembangkannya suatu transformasi Fourier cepat ( Fast Fourier Transform- FFT ) yaitu sebuah algoritma yang efisien untuk menghitung DFT ( Discrete Fourier Transform), maka telah terjadi perubahan yang besar dalam menganalisa berbagai cabang Ilmu Pengetahuan (science). Prosesor FFT yang terkecil mempunyai dua titik transformasi ( N = 2 ).
Pada tulisan ini dibahas tentang aspek-aspek komputasi dan aspek-aspek perancangan pada sistem VLSI yang berkaitan dengan perancangan prosesor FFT-DIT untuk titik transformasi sebanyak delapan buah ( N = 8 ).
Perancangan simulasi Prosesor FFT ini dilakukan dengan menggunakan teknologi CMOS. Perancangan ini dilakukan dengan menggunakan perangkat lunak CIRCAD II pada workstation HP9000 dan SUN SPARCstation 1+. Perancangan ini menggunakan modul FFT-DIT dengan N= 2 yang dirancang oleh sdr. Ir.Totok Mujiono di laboratorium CAD UI pada tahun 1990 yang lalu.
Perancangan FT-DIT untuk N = 8 ini dilakukan dengan menggabungkan modul FFT--DIT dengan N = 2 sebanyak 12 buah. Penggabungan dilakukan sesuai dengan grafik aliran sinyal dari FFT-DIT untuk N = 8 . Pada perancangan ini faktor wp ( twiddle factor ) dianggap sudah tersedia, jadi merupakan masukan dari chip prosesor FFT-DIT dengan N = 8 ini.