翻訳と辞書 |
Zak transform : ウィキペディア英語版 | Zak transform In mathematics, the Zak transform〔〔 is a certain operation which takes as input a function of one variable and produces as output a function of two variables. The output function is called the Zak transform of the input function. The transform is defined as an infinite series in which each term is a product of a dilation of a translation by an integer of the function and an exponential function. In applications of Zak transform to signal processing the input function represents a signal and the transform will be a mixed time–frequency representation of the signal. The signal may be real valued or complex-valued, defined on a continuous set (for example, the real numbers) or a discrete set (for example, the integers or a finite subset of integers). The Zak transform is a generalization of the discrete Fourier transform.〔(【引用サイトリンク】url=http://www.encyclopediaofmath.org/index.php/Zak_transform )〕 The Zak transform had been discovered by several people in different fields and was called by different names. It was called the "Gel'fand mapping" because I.M. Gel'fand introduced it in his work on eigenfunction expansions. The transform was rediscovered independently by J. Zak in 1967 who called it the "k-q representation". There seems to be a general consent among experts in the field to call it the Zak transform, since Zak was indeed the first to systematically study that transform in a more general setting and recognize its usefulness.〔〔 ==Continuous-time Zak transform: Definition== In defining the continuous-time Zak transform, the input function is a function of a real variable. So, let ''f''(''t'') be a function of a real variable ''t''. The continuous-time Zak transform of ''f''(''t'') is a function of two real variables one of which is ''t''. The other variable may be denoted by ''w''. The continuous-time Zak transform has been defined variously.
抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Zak transform」の詳細全文を読む
スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|