WIP

Port from Power Systems WIP.

Sensor-Driven Reactive Shield

Tech Level: -1 (virtually useless)

In short:

• Sensors see attack coming
• Computer calculates best time to put up shields, and where
• Shield emitters do their thing

Drawbacks:

• Useless when sensors fail
• Light-speed weapons always defeat it, as do sufficiently fast and close weapons

Polarized Open-Loop

Tech Level: 0 (obsolete, relatively easy to bypass)

The first and most basic type of shield system creates a low-power EM carrier wave through secondary emitters, and builds up a high potential in the primary emitters, utilizing complex static binding techniques to avoid full propagation. Any charged particles that contact the carrier field will create a potential difference, drawing the primary charge out of its static binding. Effectively, the primary shield will react just in time for the attack, without any need for sensor warning. The obvious drawback, that only charged attacks will trigger the reaction, is moot, as only charged attacks are subject to shielding of any kind.

However, that isn't the only disadvantage. The reliance on an attracting force is what gives this technology the "P" for "Polarized". A POL shield is either negative or positive, and reacts only to the opposite charge. The vast majority of plasma weapons have a positive charge, but some weapons are built with a negative charge, specifically to exploit this vulnerability. It is possible to alternate charges in different emitters, but it is necessary to space said emitters far enough apart to avoid short-circuiting them--and putting them so far apart means they cannot possibly cover each other's respective weakness.

Synchronized Bipolar Dipole Array

Tech level: 1 (modern, in common use, a few drawbacks)

The solution to the POL's weakness, the Bipolar version was a long time in coming. The goal was simple enough: to be able to "flip" the polarity of the shield as needed, to oppose attacks of either charge. Of course, this would necessitate discharging, reconfiguring, and recharging the emitters, not to mention some technical wizardry with the power system; in short, the implementation was not obvious.

The "eureka" moment came when an engineer recalled something about a long-forgotten type of electrical power delivery called "alternating current". Essentially, the charge could be applied to a dipole element, building a positive charge on one end, and an equal negative charge on the other. The element would physically rotate, counter to one or more adjacent, insulated elements, which ensured charge separation, and ensured that the correct charge would always be present at the correct time.

This resolved the primary drawback of the POL, albeit at a cost in overall effectiveness per unit of input energy, as only half of the stored energy was used in a given reaction. This was mostly mitigated by increasing emitter capacity, but the design retains a distinct disadvantage in recharge rate compared to POL units of similar strength.

Phased Helical Array

Tech level: 2 (advanced technology, expensive, cannot be applied to all vehicles)

Even with the POL drawback resolved, open-loop shield arrays still retained a very important weakness: each attack, regardless of strength, drained the entire emitter capacity, leaving the hull vulnerable to subsequent attacks during the recharge period. This weakness is relatively easy to exploit; by staggering attacks, firing a weak "fool" charge to clear the buffer, followed by a full-strength charge, a clever gunner can bypass a POL shield, as long as he can hit the same emitter twice during the brief recharge window. This effect can be mitigated by overlapping emitter coverage areas, or by tweaking the threshold of the static binding, but it leads to an endless arms race between gunners and shield techs, with no clear resolution.

The Phased Helical Array represented a complete rethinking of the open-loop concept, with all lessons learned from recent, large-scale wars. The first major change was to adjust the low-power carrier wave; previous implementations produced a simple, linear parabolic field--easy to understand, but ultimately the source of all their difficulties. Instead, the new emitters would cycle plasma through staggered, countered conduits, positioned just so to create a standing sinusoidal wave effect of the desired polarity. Multiple such channels would be interwoven, creating staggered waves; this would have the effect of creating a multiple helix, running parallel to the conduits in the hull, with each alternating band having opposite polarity.

An attack of either polarity, on contact with the helix, would be repelled by the like charge and attracted to the opposing charge. The resultant flux would produce a draw on the corresponding plasma loop, drawing additional power through the entire chain. While such designs had been considered before, in the single open-loop design, the passive pull was not enough to draw a matching shield reaction. However, the helical design meant that the attraction of the attacking charge would induce a counter-current in the opposed loop, creating a "push" on the backend of the plasma loop to augment the existing "pull". When all the wizardry is said and done, the attacking bolt automatically draws an equal and opposite amount of energy from the plasma loop.

Not only does this approach allow for all of the benefits of the SBDA, it does so without wasting energy in excess of the attacking bolt. Thus, the plasma loop can be charged sufficiently to ward against multiple bolts, eliminating the recharge window, or at least requiring the attack to truly overpower the shield generator, rather than tricking it into over-reacting to a false charge.

Positronium Phalanx Array

Tech Level: 3 (advanced prototype, many flaws, unstable)