Causality and negative group delays in a simple bandpass amplifier

被引：155

作者：

Mitchell, MW ^{[1
]}

Chiao, RY ^{[1
]}

机构：

[1] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA

来源：

AMERICAN JOURNAL OF PHYSICS | 1998年 / 66卷 / 01期

关键词：

D O I：

10.1119/1.18813

中图分类号：

G40 [教育学];

学科分类号：

040101 ; 120403 ;

摘要：

We demonstrate a bandpass amplifier which can be constructed from common electronic components and has the surprising property that the group delay is negative in most spectral regions. A pulse propagating through a chain of such amplifiers is advanced by several milliseconds: the output waveform precedes the input waveform. Although striking, this behavior is not in conflict with causality, as demonstrated by experiments with pulses which start or end abruptly. (C) 1998 American Association of Physics Teachers.

引用

页码：14 / 19

页数：6

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