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Communications Space Science

Hypersonic Radio Black-Out Problem Solved 88

KentuckyFC writes "Russian physicists have come up with a new way to communicate with hypersonic vehicles surrounded by a sheath of plasma. Ordinarily, this plasma absorbs and reflects radio waves at communications frequencies, leading to a few tense minutes during the re-entry of manned vehicles such as the shuttle. However, the problem is even more acute for military vehicles such as ballistic missiles and hypersonic planes. Radio blackout prevents these vehicles from accessing GPS signals for navigation and does not allow them to be re-targeted or disarmed at the last minute. But a group of Russian physicists say they can get around this problem by turning the entire plasma sheath into a radio antenna. They point out that any incoming signal is both reflected and absorbed by the plasma. The reflected signal is lost but the absorbed energy sets up a resonating electric field at a certain depth within the plasma. In effect, this layer within the plasma acts like a radio antenna, receiving the signal. However, the signal cannot travel further through the plasma to the spacecraft."
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Hypersonic Radio Black-Out Problem Solved

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  • Black out? (Score:1, Insightful)

    by Anonymous Coward on Friday January 07, 2011 @02:14PM (#34793920)

    Is this PC? Maybe use "slave out"? What do you think, Linda?

  • by si3n4 ( 540106 ) on Friday January 07, 2011 @02:39PM (#34794240)
    thanks for the comment - I realize this quickly devolved into a discussion about what was or wasn't said in the article but it is interesting that the shape of the vehicle can create a hole in this plasma and thus provide another solution to the issue . Maybe it's not always possible to design the object involved to create this hole and the plasma antenna is a useful alternative, but in any case it was interesting to me to know this other 'solution' exists....
  • by geekoid ( 135745 ) <dadinportlandNO@SPAMyahoo.com> on Friday January 07, 2011 @02:40PM (#34794254) Homepage Journal

    You're really limit in your thinking.

    Technology is constantly developed to make killing more precise; which means LESS killing.

    And there are a hell of a lot of spin-offs that are used in civilian markets. I don't see why you have created some sort of demarcation between killing tech and non killing tech. there is just tech that is used. The same tech is often used for killing as it used for non killing.

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