翻訳と辞書 |
Pulsed radiofrequency : ウィキペディア英語版 | Pulsed radiofrequency Pulsed radiofrequency is the technique whereby radio frequency (RF) oscillations are gated at a rate of pulses per second (cycles per second, defined as a hertz (Hz)). Radio frequency energies occupy 1.0 x 104 Hz to 3.0 x 1011 Hz of the electromagnetic spectrum. Radio frequency electromagnetic energy is routinely produced by RF electrical circuits connected to a transducer usually called an antenna.〔The ARRL Handbook for Radio amateurs. Newington, The American Radio Relay League, Inc. CT, 06111 USA, 1997, ISBN 0-87259-174-3〕 ==Pulsed radio frequency waveforms== The figure below shows an example of a generalized pulsed radio frequency waveform as seen with an oscilloscope with an antenna probe. In this example there are 1000 pulses per second (1 kHz pulse rate) with a gated pulse width of 42 µs. The pulse packet frequency in this example is 27.125 MHz of RF energy. The duty cycle for a pulsed radio frequency is the percent time the RF packet is on, 4.2% for this example ((X 1000 pulses divided by 1000 ms/s ) X 100). The pulse packet form can be a square, triangle, ramp or sine wave.〔 In several applications of pulse radio frequency, such as radar,〔Le Chevalier, Francois, Principles of Rader and Sonar Signal Processing, Artech House, Boston, London, 2002. ISBN 1-58053-338-8〕 times between pulses can be modulated.
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「Pulsed radiofrequency」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.
|
|