翻訳と辞書 Words near each other ・ "O" Is for Outlaw ・ "O"-Jung.Ban.Hap. ・ "Ode-to-Napoleon" hexachord ・ "Oh Yeah!" Live ・ "Our Contemporary" regional art exhibition (Leningrad, 1975) ・ "P" Is for Peril ・ "Pimpernel" Smith ・ "Polish death camp" controversy ・ "Pro knigi" ("About books") ・ "Prosopa" Greek Television Awards ・ "Pussy Cats" Starring the Walkmen ・ "Q" Is for Quarry ・ "R" Is for Ricochet ・ "R" The King (2016 film) ・ "Rags" Ragland ・ ! (album) ・ ! (disambiguation) ・ !! ・ !!! ・ !!! (album) ・ !!Destroy-Oh-Boy!! ・ !Action Pact! ・ !Arriba! La Pachanga ・ !Hero ・ !Hero (album) ・ !Kung language ・ !Oka Tokat ・ !PAUS3 ・ !T.O.O.H.! ・ !Women Art Revolution Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク heterodyne detection ： ウィキペディア英語版 heterodyne detection Heterodyne detection is a method of detecting radiation by non-linear mixing with radiation of a reference frequency. It is commonly used in telecommunications and astronomy for detecting and analysing signals. The radiation in question is most commonly either radio waves (see superheterodyne receiver) or light (see Optical heterodyne detection or interferometry). The reference radiation is known as the local oscillator. The signal and the local oscillator are superimposed at a mixer. The mixer, which is commonly a (photo-)diode, has a non-linear response to the amplitude, that is, at least part of the output is proportional to the square of the input... The received signal can be represented as :$E\_\backslash mathrm\; \backslash cos(\backslash omega\_\backslash mathrmt+\backslash varphi)\backslash ,$ and that of the local oscillator can be represented as :$E\_\backslash mathrm\; \backslash cos(\backslash omega\_\backslash mathrmt).\backslash ,$ For simplicity, assume that the output ''I'' of the detector is proportional to the square of the amplitude: :$I\backslash propto\; \backslash left(\; E\_\backslash mathrm\backslash cos(\backslash omega\_\backslash mathrmt+\backslash varphi)\; +\; E\_\backslash mathrm\backslash cos(\backslash omega\_\backslash mathrmt)\; \backslash right)^2$ :$=\backslash frac\backslash left(\; 1+\backslash cos(2\backslash omega\_\backslash mathrmt+2\backslash varphi)\; \backslash right)$ ::$+\; \backslash frac(1+\backslash cos(2\backslash omega\_\backslash mathrmt))$ :: \right ) :$=\backslash underbrace^2\}\}\_+\backslash underbrace\backslash cos(2\backslash omega\_\backslash mathrmt+2\backslash varphi)\; +\; \backslash frac\backslash cos(2\backslash omega\_\backslash mathrmt)\; +\; E\_\backslash mathrmE\_\backslash mathrm\; \backslash cos((\backslash omega\_\backslash mathrm+\backslash omega\_\backslash mathrm)t+\backslash varphi)\}\_$ ::$+\; \backslash underbrace\; \backslash cos((\backslash omega\_\backslash mathrm-\backslash omega\_\backslash mathrm)t+\backslash varphi)\}\_.$ The output has high frequency ($2\backslash omega\_\backslash mathrm$, $2\backslash omega\_\backslash mathrm$ and $\backslash omega\_\backslash mathrm+\backslash omega\_\backslash mathrm$) and constant components. In heterodyne detection, the high frequency components and usually the constant components are filtered out, leaving the intermediate (beat) frequency at $\backslash omega\_\backslash mathrm-\backslash omega\_\backslash mathrm$. The amplitude of this last component is proportional to the amplitude of the signal radiation. With appropriate signal analysis the phase of the signal can be recovered as well. If $\backslash omega\_\backslash mathrm$ is equal to $\backslash omega\_\backslash mathrm$ then the beat component is a recovered version of the original signal, with the amplitude equal to the product of $E\_\backslash mathrm$ and $E\_\backslash mathrm$; that is, the received signal is amplified by mixing with the local oscillator. This is the basis for a Direct conversion receiver. ==See also== *Heterodyne *Homodyne detection *Optical heterodyne detection 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「heterodyne detection」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.