Re: Sensors

At 11:35 PM +0200 5/29/01, Derk Groeneveld wrote:
>  > That assumes that targets are emmitting. A target at total
>>  EMCON will presumably be relying on totally passive sensors.
>>  Say a vessel (in space) moving ballistically and not
>>  thrusting.
>>
>>  By relying on ESM systems you are looking at the various
>>  fire control radars, navigation radars, long range
>>  communications, search radar, weather scopes, data links,
>>  Talk between ships radio, and other electronic garbage that
>>  ships emmit.
>
>Yes. But so is any passive sensor.
>

I'm not sure what you are saying here. Is it that Passives are like 
the above ESM? I was essentially talking about Passives.

>  > Further, just relying on passive sensors to recognize a
>>  vessel will lead to funny incidents of "seeing" a harmless
>>  tanker when in reality it is a CVA dressed up with the same
>>  active emmissions.
>
>Then again, there's the same risk with active sensors. Also, you;'re
>assuming everything CAN be disguised/masked (see below, engines
discussion)

Ahh, but with actives and passives you'll have more information to 
make your decision. Passives are using your eyes and ears in a dark 
room. Active is using a little pen light to see a specific object. 
(naturally you know this)

>
>Similarly, a sailing vessel can be given a nimitz-size reflection by
using
>a simple retro-reflector...
>

Reflection against what? Passives?  And from what aspect? (Space is 
3D, much harder to predict your aspect) It'll be hard to disguise a 
sailing vessel from mm wave radar. A decent mm wave set can pick out 
what style of rigging one would have.

The only thing I'd think that mm wave radar would have a hard time 
with would be a very well done Q-ship. Besides, the whole principle 
of mm-wave radar and its fine resolution is the basis for the ability 
of Enhanced and Superior sensors to figure out what the current 
status of a vessel is. ("Ok, his drives are down and geeze look at 
that big hole in his port side weapons array, he's definately weak on 
that side sir. His VLS system looks mostly popped too, so he's not 
got much fight left in him...")
>
>Yes, but you're not going to do much ranging until you've acquired the
>target, meaning that EITHER passive sensors were good enough to acquire
>the target, OR you had to go active anyhow.

Ranging can be accomplished with passives too. 
Inferometric/stadio-metric triangulation.
I don't see needing Cepheid variables to figure out how far away that 
Eurie BDN is...

>
>Similar to modern passive sonar, where the noise can be related to
>specific ships.
>

I suspect that one would be able to tell what mass/drive power the 
ship is by the Main drive/maneuvering drive efflux. Lots of charged 
ions and you've got a big ship or a small ship using lots of power. 
Figure out the Delta Vee and you've got the Mass and Drive Power at 
that time Pegged. That closes your envelope of possible ships by a 
large margin.

>  > So I guess the question is, what kind of drives are they?
>>  Thats the first thing.
>>
>>  Second is how much passive emmissions do the ships give off?
>>  You know something is there. How far beyond 54" do you know?
>>  (TK drive emmissions are another thing, boy this long range
>>  sparky stuff gets tricky...)
>
>Yup. So what PSB do you want to make up for your desired game effect?
;)

Hmm, Captured Singularities by 2180s? I dunno, whats the author say?
Jon?

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