Exploring the Plausibility of SF Energy Shield Alternatives

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Discussion Overview

The discussion explores potential alternatives to science fiction (SF) energy shields, focusing on theoretical and speculative concepts for protecting spacecraft from high-velocity threats. Participants examine various ideas, including plasma windows, Whipple shields, and other advanced materials or technologies, while considering the limitations and challenges of current scientific understanding.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that Whipple shields could be effective against high-speed, low-mass threats by dispersing incoming projectiles before they reach the main armor.
  • Others suggest the use of mini-robot clouds that could ionize and redirect incoming materials, potentially providing a form of active defense.
  • A participant mentions the concept of a plasma window, which could theoretically shatter hyper-velocity projectiles if sufficient power is applied, but acknowledges the current limitations in energy management.
  • Some argue that the energy requirements for effective plasma windows or energy shields are beyond current technological capabilities and would require significant breakthroughs.
  • There is a discussion about the practicality of using multilayered ablative-reactive combinations as a form of protection, though this is not considered a true energy shield.
  • Participants note that while advanced technologies may offer some protective capabilities, they are unlikely to resemble the energy shields depicted in science fiction.
  • Some express skepticism about the effectiveness of shielding in space combat, suggesting that high-tech vessels may still be vulnerable to low-tech tactics.

Areas of Agreement / Disagreement

Participants express a range of views, with no consensus on the feasibility of proposed shielding technologies. While some ideas are explored, there remains significant uncertainty about their practicality and effectiveness in real-world applications.

Contextual Notes

Limitations include the current understanding of energy management, the challenges of waste heat in spacecraft, and the speculative nature of many proposed technologies. The discussion also highlights the complexities of space combat and the potential for asymmetrical warfare.

Who May Find This Useful

Readers interested in theoretical physics, aerospace engineering, and science fiction concepts related to space defense may find this discussion relevant.

  • #31
trurle said:
Spark gap do extra-thermal emission at RF; most of RF generation of spark is due current instabilities ans tails off at about 400-500 MHz. The cutoff frequency is actually have to do with air pressure, not feeding voltage/current. Lower harmonics can extend the jamming band roughly to 1.3 GHz.

Regarding "brute force" jamming, it do not work well with LTE (4G) commlinks. LTE tolerate by standard 0.3 mW of in-band interference per antenna. With typical 5 cm patch antennas, tolerance is 0.12 W/m2. With typical heavy-track based military jammer having 30 kW output, the effective (omnidirectional) jamming is achieved at distance 140 meters. Or may be even 5-15m meters if drone use a MIMO antenna array. This number shows it is pretty difficult to jam a large swarm of drones.
There are already jammer rifles directed at drones.
 
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  • #32
GTOM said:
There are already jammer rifles directed at drones.
Yes. With them you can temporarily disable one drone at time at few hundred meters distance. Well, if you consider this device effective, i have no objections.
 
  • #33
trurle said:
Spark gap do extra-thermal emission at RF; most of RF generation of spark is due current instabilities ans tails off at about 400-500 MHz. The cutoff frequency is actually have to do with air pressure, not feeding voltage/current. Lower harmonics can extend the jamming band roughly to 1.3 GHz.

Regarding "brute force" jamming, it do not work well with LTE (4G) commlinks. LTE tolerate by standard 0.3 mW of in-band interference per antenna. With typical 5 cm patch antennas, tolerance is 0.12 W/m2. With typical heavy-track based military jammer having 30 kW output, the effective (omnidirectional) jamming is achieved at distance 140 meters. Or may be even 5-15m meters if drone use a MIMO antenna array. This number shows it is pretty difficult to jam a large swarm of drones.

If you take out the omni directional aspect, maybe have a beam that sweeps, similar to a radar, or more a more focused beam that covers a portion of a hemisphere. I think given power/weight limits in smaller drones they are unlikely to be super sonic for example, so they are not going to cover a lot of ground very quickly. But a question would be what happens when the jamming signal is removed, if its not strong enough to damage the drone, it will likely just resume what it was doing.

You'd want to probably combine this with some sort of detection/aiming so swarms of drones can be detected on approach and brought down with a powerful truck mounted micro wave "flash light" rather than having this thing constantly jamming everything, including your own transmissions.

As a side note, I would have thought a vehicle based jammer would have a bit more power than 30kW!
 
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  • #34
Interesting video. Latter on you get a ground based view, they certainly announce their arrival acoustically!

 
  • #35
Bab5space said:
Depends on how sophisticated and ruthless the AI he is trying to hack is does it not?

Hacking requires a link does it not? And upon a hacker being detected, I am certain the AI would be sending whatever appropriate level of force is required to 'neutralize' the threat.

Star Trek makes me laugh. Sending in away times via teleport in harm's way often when they could be sending drones.

I guess they did not foresee drone technology as being huge in the future.
Wouldn't have that been exciting television? Watching a bunch of guys sitting around, sipping coffee while operating drones.
The tension and drama from an action adventure show comes from placing your characters in peril. Even the transporter, a invention to allow a quick way of getting characters into the action was a two-edged sword. It could pull them out of trouble just as easily as it put them there. Thus so many plots had to include a reason why they could not use the transporter to return to the ship.
 
  • #36
Janus said:
Wouldn't have that been exciting television? Watching a bunch of guys sitting around, sipping coffee while operating drones.
The tension and drama from an action adventure show comes from placing your characters in peril. Even the transporter, a invention to allow a quick way of getting characters into the action was a two-edged sword. It could pull them out of trouble just as easily as it put them there. Thus so many plots had to include a reason why they could not use the transporter to return to the ship.

As there are several ways to cook an egg, there are several ways to create tension and danger for characters if that's what you want.

Sabotage? Traitors? Enemy attack on the control ship? There is still plenty tension to go around if that's what you want.

By the time our heroes are marooned on an alien world they are losing anyway, so it won't be the norm as I do not write Star Trek.
 
  • #37
essenmein said:
As a side note, I would have thought a vehicle based jammer would have a bit more power than 30kW!
Military guys would also like to have more power. Unfortunately, 30 kW jammer is what possible on a single 8x8 truck with current tech.
 
  • #38
Been a few years but, when RAF were practising 'Time over Target' attacks prior to Iraq 1 or 2, their jets' late-morning pass over our local airport, with radars & jammers at 'full military power', knocked out lots of our lab equipment.

Having a dozen high-end data collection systems go 'graaak' and re-boot mid-run was seriously bad news. We could not just resume, we had to cold-start, re-do pre-run suitability checks. One afternoon, the RAF made a second pass and everything went down again. Our late shift kindly completed the pre-run checks, launched half the batch analyses planned...
 

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