Someone suggested you can get a firing solution on a target with passive
sensors (although it is difficult). Good to know (I kind of suspected
so).
Someone (Mr. Beast I believe) suggested that active sensors almost always
outrange passive sensors. I have to question this. On Earth, passive sensors
tend to have somewhat limited range partly due to the effects of being inside
a noisy atmospheric envelope. And radars can bang signal out to a few hundred
miles without too much problem (just lots of juice).
However, I question this comment as it pertains to space for several reasons:
our most sensitive instruments (such as those on Hubble or other similar sats)
are probably passive, and can see far farther and far more minor changes than
any active system I'm aware of. I'd suspect (no gaurantees:) that in 2183,
this translates to passive systems that can detect very discreet phenomena at
long distances.
Active systems would be limited by the fact that the density of energy (which
is a contributor to reflected signal strength) will drop off as the square of
distance... so I think it'd be pretty imaginative to say these systems will be
able to detect things 100,000 or more km away.... I would think active systems
would be limited to a far more restricted distance. They'd offer you faster
and more precise data than a passive system, but have a much more limited
range.
Now, this assumes every stardrive doesn't emit a field everyone and their
cousin can pick up with a passive sensor from across a star system. (which
they do in Star Trek for example).
I would think passive systems offer two advantages over active systems: 1)
They don't reveal the firer by producing emissions 2) They allow one to gain
information about a foe at greater distances (albeit limited information)
Active systems would offer two advantages: 1) A better resolution of data
(higher level of information)
2) Data available relativly quickly - necessary for a fire control
solution against a manoeuvring foe
Further, is Fire Control something only turned on when you know where your
opposition is and you don't mind if they know they're a target? That is to
say, you don't use it for searching... its use is to turn that bogey or soft
lock you have into a hard lock ("Ping them so hard you could map their
hull...") which will allow pinpoint fire.
Comments? Disagreements? Noam or Mark might have something to say to the
ranges of passive instrumentation in space. <Of course, their application is
non-military and not oriented around trying to get a firing solution...>
<I'll note that my comments reflect I'm A) one of the 'space is like sub
warfare' crowd and B) I enjoy electronic warfare options in games... so I'm
considering the "whole nine yards" version of things before I worry about
how it could be simplified - lots of good advice on how that might work
so far from Dean, Beast, and others...>
> "Thomas.Barclay" wrote:
Most of this post I can agree with, but I'm not sure about faster information.
I would think that BY DEFINITION passive sensors HAVE to give more recent
information. Passive sensors obtain information from the target's emmissions,
thus the information that they obtain has travelled one way (in space, at
least, probably at the speed of light). Active sensors, on the other hand,
work by bouncing something off the target, thus making a round trip (again at
the speed of light). I'm having some difficulty imagining that a round trip at
a given speed is
faster than a one-way trip at the same speed. Maybe someone else could
explain this.
On Tue, 11 Apr 2000 15:53:58 -0400 "Thomas.Barclay"
> I would think passive systems offer two advantages over active
<snip>
> <I'll note that my comments reflect I'm A) one of the 'space is like
Passive systems are the system of choice of modern submarines, although there
was a scenario in one of the Harpoon sets where you are in a SSN looking for a
SS (electric = near silent) lurking at the mouth of the Med. Going active (you
can outrun their torps but they most likely
cannot out-run yours) was suggested as a weapon of choice. It worked
for
me about 5/7 times - one time I was randomly deployed on top of one of
the bad guys - at least 3 seconds (real time) into the game, before I
could go active, I was dodging inbound transients - next time I waited
too long to go active and got sandwiched between inbound torp and electric
boat behind me, ran right into the second sub's torp! (sneaky scenario never
said there was only ONE of them.)
Although it is fiction, there is a scene in the book "Choosers of the Slain"
by James H. Cobb where the Argentine sub (SS) hunting the new American stealth
destroyer (?) uses one ping to confirm the firing solution. Page 201, if you
have the book.
Gracias.
Glenn Wilson, Triple Threat Wargamer - (loses equally well in
SF/Fantasy/Historical Games.) Prefers Fantasy Dwarves, Starguard
Science
Fiction, 1500-1700 North America Skirmishes, the First Crusade, and most
anything prior to firing pins and Machine Guns
I assume that the passive system gives you SOME information faster, but that
the active system gives you a faster firing solution (not the same thing,
really).
I too am of the "space warfare will probably be similar to sub warfare"
school of thought--though some may take that analogy too far-space
doesn't have thermoclines after all!
Having said that, I prefer my space games to be a bit simpler (that's why I
like FT/FB). My PSB? Power generators and anti-grav drives give off
way
too much signature to be masked--so everyone knows where you are (just
not whatr you are, necessarily).
Rob
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On Wed, 12 Apr 2000 18:58:56 -0400 "Robert W. Hofrichter"
> <RobHofrich@peoplepc.com> writes:
Hmmm, should have listened in that astronomy class. How about 'sensor
shadow' effect of planets (Jupiter), asteroid belts and/or "radiation
belts" (Van Allen?) - the last is a stretch, I acknowledge.
> Having said that, I prefer my space games to be a bit simpler (that's
Good thought and provides more reason to prefer a passive sensor system.
Gracias.
Glenn Wilson, Triple Threat Wargamer - (loses equally well in
SF/Fantasy/Historical Games.) Prefers Fantasy Dwarves, Starguard
Science
Fiction, 1500-1700 North America Skirmishes, the First Crusade, and most
anything prior to firing pins and Machine Guns
My item about thermoclines also referred to the fact that they can
EXTEND your sensor range in some cases--something "radar shadow" does
not do :-)
And even when it comes to the sensor blocking effect of thermoclines, it's not
strictly analogous to planets, etc, creating sensor shadows. Maybe similar to
a nebula., depending upon the flavor of your favorite psb?
Rob
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