How the U.S. Army’s ‘Phaser’ can wipe out an entire fleet of drones

Re:How the U.S. Army’s ‘Phaser’ can wipe out an entire fleet... by JoeAltmaier on Wednesday November 16, 2016 @03:06PM (#12970950)

I think they are magically 100% effective. Unless the cage is breached, nothing will get through. However, an EMP pulse could melt holes in the foil.

However it also means the drone has no GPS; no wireless signaling; no sensors outside the foil at all. It becomes a dumbfire dead-reckoning device.

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Re:How the U.S. Army’s ‘Phaser’ can wipe out an entire fleet... by Florin_Andrei on Wednesday November 16, 2016 @03:17PM (#12971057)

> I think they are magically 100% effective.

No, they are not. Even a continuous, zero-hole metallic bubble will leak some radiation inside, depending on frequency, nature of material, wall thickness, etc.

Start here:

https://en.wikipedia.org/wiki/Penetration_depth

then continue reading about absorbance, skin effect, etc.

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Re:How the U.S. Army’s ‘Phaser’ can wipe out an entire fleet... by JoeAltmaier on Wednesday November 16, 2016 @03:34PM (#12971209)

I see. Only for zero-resistance metal would skin depth be zero.

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Re:How the U.S. Army’s ‘Phaser’ can wipe out an entire fleet... by JoeAltmaier on Thursday November 17, 2016 @09:16AM (#12977594)

At microwave frequencies, skin depth is essentially zero (microns anyway) for most metals. So until the bag is melted, nothing will get through.

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