Chaff jamming is one of passive jamming modes, which is used widely and is a great threat to radar.

箔条干扰是一种常用的无源干扰，对雷达构成极大的威胁。

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Counsel for Anthony McIntyre also accused police of being "passive, bordering on cavalier" over the alleged increased threat to him.

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Protecting the United States against the evolving EMP threat will require a mix of active defenses, passive defenses, and policy changes.

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And by putting the gravest threat the US presently faces from the Middle East in the passive voice, he made clear that actually, the US isn't going to do anything about it.

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