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Message no. 1
From: Gurth <gurth@******.NL>
Subject: jamming laser communications
Date: Fri, 3 Mar 1995 11:20:25 +0100
>> What I meant with shining a laser in the receiver to jam transmissions was
>> for _communications_, not for LGBs. How on earth would you keep a laser
>> exactly pointed at the nose of a falling bomb??
>
> Exactly. How on earth would you keep a laser exactly pointed at
>the communications pod on the underwing of a tactical fighter? Or the
>emitter dish of an AWACs?

I can't recall anyone saying that the laser communications were to or from
aircraft (though I didn't really read all those long messages). For jamming
laser receivers on aircraft it would be useless, but imagine a receiver set
up somewhere in a field or on a building -- if you can locate the receiver
you can shine a laser into it (better make it do random pulses otherwise
they can filter out what the message you're trying to jam).


Gurth@******.nl - Gurth@***.nl - http://www.xs4all.nl/~gurth/index.html
Walk this world with me
Geek Code v2.1: GS/AT/! -d+ H s:- !g p?(3) !au a>? w+(+++) v*(---) C+(++) U
P? !L !3 E? N++ K- W+ -po+(po) Y+ t(+) 5 !j R+(++)>+++$ tv+(++) b+@ D+(++)
B? e+ u+@ h! f--(?) !r(--)(*) n---->!n y?
Message no. 2
From: Sam Thomas <sinbad@********.COM>
Subject: Re: jamming laser communications
Date: Fri, 3 Mar 1995 12:26:28 -0600
Gurth writes,

>I can't recall anyone saying that the laser communications were to or from
>aircraft (though I didn't really read all those long messages). For jamming
>laser receivers on aircraft it would be useless, but imagine a receiver set
>up somewhere in a field or on a building -- if you can locate the receiver
>you can shine a laser into it (better make it do random pulses otherwise
>they can filter out what the message you're trying to jam).

You are definetly on the right track, you can also defocuss the beam alittle
to give you better coverage.

Sinbad Sam
Message no. 3
From: Adam Getchell <acgetche@****.UCDAVIS.EDU>
Subject: Re: jamming laser communications
Date: Fri, 3 Mar 1995 15:09:44 -0800
On Fri, 3 Mar 1995, Gurth wrote:

> I can't recall anyone saying that the laser communications were to or from
> aircraft (though I didn't really read all those long messages). For jamming

The point was I suggested for aircraft security a black box that
would send a coded laser squirt to its owning company to inform them that
it had been taken over, what they looked like, their weaponry, etc. etc.
So one would have to be able to jam the commo pulse from an aircraft to
render this ineffective.
I don't think it can be done. Sinbad Sam has said otherwise, but
(so far) hasn't offered any proof.

> Gurth@******.nl - Gurth@***.nl - http://www.xs4all.nl/~gurth/index.html

========================================================================
Adam Getchell "Invincibility is in oneself,
acgetche@****.engr.ucdavis.edu vulnerability in the opponent."
http://instruction.ucdavis.edu/html/Adam/getchell.html
Message no. 4
From: Sam Thomas <sinbad@********.COM>
Subject: Re: jamming laser communications
Date: Fri, 3 Mar 1995 18:50:16 -0600
Adam Getchell writes,

> The point was I suggested for aircraft security a black box that
>would send a coded laser squirt to its owning company to inform them that
>it had been taken over, what they looked like, their weaponry, etc. etc.
>So one would have to be able to jam the commo pulse from an aircraft to
>render this ineffective.
> I don't think it can be done. Sinbad Sam has said otherwise, but
>(so far) hasn't offered any proof.

One point to make is how does the black box know where to send the squirt
so to speak. To have realistic chance the black box would have to interfaced
with other external sensors such a GPS, and then it would have to figure out
necessary angles and event horizons. The black box could have the needed
tronix inside but it will have to know where the plane currently is. This
included tronix will drive the cost up. It also causes a weak link in the
security envelope so to speak. Also the transmitter will have to be
stabilized in atleast two planes of motion, to have a chance of staying on
track with the target reciever. It could also have the squirt directed
at an overhead sat in goesync, but this multiplies the possible problems.
That would mean the black box would ahve to have someway of having the
codes that would allow the signal to be accepted by the sat. Gee those
codes could have some value to runners and other corps. The codes would
have to have someway to get the codes updated periodically. Again opening
up another security problem that will have to dealt with. Again all of this
drives up the price and multiplies the security problems. The greater the
complexity of the black box the greater the cost and maintenance problems.

Applying the KISS principle I would use a RF transmitter with a broad
range antenna (Omi-directional). All that the transmitter would have to
send is its coded ID sequence. Then all the corp has to do is triangulate
the signal location, course and speed. Today you need only one reciever
to perform the triangulation. Triangulating reciever could be airbourne
(LTA drone, etc), on a high point or mounted in surface vehicle.

FYI laser comms are usable only if the transmitter and reciever locations
are known to an extremely accurate precision. Moving platforms that have a
need to communicate on the fly use other methods one being bouncing the
signal off several sats and then the sat redirects the signal to the intended
receptent. This type of method does not use/need a laser beam generally it
is scrambled microwave pulses or a maser. The maser is preferable to the
laser due to it does not have the atmospheric conditons problems that lasers
have.

Again laser/maser communicators today can be jammed so in 2054 they will
jammed. As to my proof well get out of your physics classes and get the
"UNCLASSIFED" documents that should be in any reasonably competent college
library. I do not have any other way to tell you with out violating several
agreements that I signed upon leaving. Direct seems to the only way, I am
unable to impart an understanding of the principles required to do the
jamming without verifying your clearance and your need to know. I hope that
is clear enough to you.

Sinbad Sam
"There are none so blind as those that will not see"
Message no. 5
From: Adam Getchell <acgetche@****.UCDAVIS.EDU>
Subject: Re: jamming laser communications
Date: Fri, 3 Mar 1995 17:45:55 -0800
On Fri, 3 Mar 1995, Sam Thomas wrote:

> One point to make is how does the black box know where to send the squirt
> so to speak. To have realistic chance the black box would have to interfaced

Ring laser gyros are relatively cheap.
Inertial sensors in the box (see above), plus a nice table of
company comm satellite orbits. A timepiece, some processing, and voila!
from black box to comm sat, no time flat.
If someone wanted the table of orbits, say, they'd have to defeat
the black box and successfully unencrypt the data, which could be
encrypted with a OTP (ask Rat) so no such luck.

> codes that would allow the signal to be accepted by the sat. Gee those

Codes that are only used once, in the event of hijacking, could
also be encrypted with the Vernan cipher. No way to break it, chummer.

> is scrambled microwave pulses or a maser. The maser is preferable to the
> laser due to it does not have the atmospheric conditons problems that lasers

2500 nanometer and 25000 nanometer bands also do not have
significant atmospheric dispersion. Infrared would provide higher signal
density than microwave.

> Sinbad Sam

========================================================================
Adam Getchell "Invincibility is in oneself,
acgetche@****.engr.ucdavis.edu vulnerability in the opponent."
http://instruction.ucdavis.edu/html/Adam/getchell.html
Message no. 6
From: Sam Thomas <sinbad@********.COM>
Subject: Re: jamming laser communications
Date: Fri, 3 Mar 1995 20:48:04 -0600
Adam Getchell writes,

> Ring laser gyros are relatively cheap.
> Inertial sensors in the box (see above), plus a nice table of
>company comm satellite orbits. A timepiece, some processing, and voila!
>from black box to comm sat, no time flat.

Good points but gyros and other sensors have to referenced to the main
gyro onboard, and you also have to have antennna that can be brought to
bear upon the desired bearing and angle. But it will have to be stabilized
to achieve an accurate lock on the target. Also most sat commuications
have a two way link up.

> Codes that are only used once, in the event of hijacking, could
>also be encrypted with the Vernan cipher. No way to break it, chummer.

You might want to pay the crypto areas of internet. The Puzzle Place can and
has broken the "unbreakable" codes in the past and present. No code is
"unbreakable" to "crack" code merely requires processing speed, time
and
the will to let contimue until broken. I agree that the average corp present
does not even come close to having the processors to "crack" a good code
scheme, but in Shadowrun there already is inplace devices that have
a better than average chance to "crack" any encryption. I agree in light of
what is needed to "crack" a code to day these devices seem more magic than
science.

> 2500 nanometer and 25000 nanometer bands also do not have
>significant atmospheric dispersion. Infrared would provide higher signal
>density than microwave.

Yes you are correct but I was using a KISS example only. To me my example
would work out very nicely with a low cost and a fairly high level of
security. It would also offer the players a remote chance of pulling off
a hi jack.

Sinbad Sam
Message no. 7
From: LISETTE M THERIOT <psy_lmt@***.LAMAR.EDU>
Subject: Re: jamming laser communications
Date: Fri, 3 Mar 1995 22:16:43 -0600
>> I can't recall anyone saying that the laser communications were to or from
>> aircraft (though I didn't really read all those long messages). For jamming
>
> The point was I suggested for aircraft security a black box that
>would send a coded laser squirt to its owning company to inform them that
>it had been taken over, what they looked like, their weaponry, etc. etc.
>So one would have to be able to jam the commo pulse from an aircraft to
>render this ineffective.
> I don't think it can be done. Sinbad Sam has said otherwise, but
>(so far) hasn't offered any proof.
>
>> Gurth@******.nl - Gurth@***.nl - http://www.xs4all.nl/~gurth/index.html
>
>=========================================================================
>Adam Getchell "Invincibility is in oneself,
>acgetche@****.engr.ucdavis.edu vulnerability in the opponent."
>http://instruction.ucdavis.edu/html/Adam/getchell.html
>=========================================================================

I Know this sounds a little niave (sp?), but what about putting chewing-gum
over the transmiter?

Twap at will...

Nathan Ray (Lissete Theriot's Account)

psy_lmt@***.lamar.edu
Geek Code V2.1 G! d? H s+ g+ p? au0 a13 w+++>w v++ c++++ U p? !3 E? N+ K- w---

M++ !V -po+ (po---) Y+ t+ 5-- !j R++ G+ tv b+++ !D B---(Kill Him!) e* u++
h!>h++ f* !r n----(n+++) !y+
Message no. 8
From: Gurth <gurth@******.NL>
Subject: Re: jamming laser communications
Date: Sat, 4 Mar 1995 11:13:12 +0100
>I Know this sounds a little niave (sp?), but what about putting chewing-gum
>over the transmiter?

This does sound naive... to put chewing gum over the transmitter you need to
get really close to it (or use a slingshot or something :), which is a bit
impractical if the transmitter is on a flying aircraft. I still believe you
can jam the receiver by shining a laser into it... I didn't really
understand all of Adam's reasoning (never paid much attention in physics
class, thanks to my "very entertaining" (more like the opposite) teacher),
but my reasoning is as follows: if the receiver is set up for a certain
frequency of laser, you could use the same frequency laser to blind it, in
that way the actual transmitter would not be noticed because the receiver is
continually illuminated by the jammer...


Gurth@******.nl - Gurth@***.nl - http://www.xs4all.nl/~gurth/index.html
Blabbering on like rubbish there...
Geek Code v2.1: GS/AT/! -d+ H s:- !g p?(3) !au a>? w+(+++) v*(---) C+(++) U
P? !L !3 E? N++ K- W+ -po+(po) Y+ t(+) 5 !j R+(++)>+++$ tv+(++) b+@ D+(++)
B? e+ u+@ h! f--(?) !r(--)(*) n---->!n y?
Message no. 9
From: Sam Thomas <sinbad@********.COM>
Subject: Re: jamming laser communications
Date: Sat, 4 Mar 1995 12:01:24 -0600
Gurth writes,

>This does sound naive... to put chewing gum over the transmitter you need to
>get really close to it (or use a slingshot or something :), which is a bit
>impractical if the transmitter is on a flying aircraft. I still believe you
>can jam the receiver by shining a laser into it... I didn't really
>understand all of Adam's reasoning (never paid much attention in physics
>class, thanks to my "very entertaining" (more like the opposite) teacher),
>but my reasoning is as follows: if the receiver is set up for a certain
>frequency of laser, you could use the same frequency laser to blind it, in
>that way the actual transmitter would not be noticed because the receiver is
>continually illuminated by the jammer...

You are quite right about the basic principles. I believe that I had a similar
type of physics teacher too.

Off subject I would like to thank you for the work, effort and creativity that
you have put into the "Running Gear" And "Tech Specs". Truly both of
them are
works that show you knowledge of Word for Windows. How long did it take you
to get the templates made up. By the way have you heard about Microsoft's
"Internet Assistant", which allows you to browse the WWW using Word for
Windows? It is in Beta testing but available on the Microsoft FTP and Home
page.

Sinbad Sam
Message no. 10
From: Gurth <gurth@******.NL>
Subject: Re: jamming laser communications
Date: Sun, 5 Mar 1995 11:45:53 +0100
>Off subject I would like to thank you for the work, effort and creativity that
>you have put into the "Running Gear" And "Tech Specs". Truly both
of them are
>works that show you knowledge of Word for Windows. How long did it take you
>to get the templates made up.

Glad you like them :) (anybody who doesn't know what he's talking about,
check out the Shadowrun section of my WWW page, the URL is in my signature).
I didn't really use a template (I tried making one once and ended up erasing
normal.dot :( ), but it wasn't too much work I think. Just mess around with
tables and lines and borders and stuff and you'll get results eventually :)

>By the way have you heard about Microsoft's
>"Internet Assistant", which allows you to browse the WWW using Word for
>Windows? It is in Beta testing but available on the Microsoft FTP and Home
>page.

Nope, haven't heard about it. I use Mosaic (some strange version I think,
because it doesn't appear to have half the options I heard it should
have...) I did try faxing with Word once, but that didn't quite work...


Gurth@******.nl - Gurth@***.nl - http://www.xs4all.nl/~gurth/index.html
Blabbering on like rubbish there...
Geek Code v2.1: GS/AT/! -d+ H s:- !g p?(3) !au a>? w+(+++) v*(---) C+(++) U
P? !L !3 E? N++ K- W+ -po+(po) Y+ t(+) 5 !j R+(++)>+++$ tv+(++) b+@ D+(++)
B? e+ u+@ h! f--(?) !r(--)(*) n---->!n y?
Message no. 11
From: Adam Getchell <acgetche@****.UCDAVIS.EDU>
Subject: Re: jamming laser communications
Date: Mon, 6 Mar 1995 09:34:32 -0800
On Sat, 4 Mar 1995, Gurth wrote:

> frequency of laser, you could use the same frequency laser to blind it, in
> that way the actual transmitter would not be noticed because the receiver is
> continually illuminated by the jammer...

To successfully jam the receiver, you need your jamming intensity to be
on the same level as the emitter intensity ... this occurs when the
jammer is a lot closer to the receiver than the emitter ... or the jammer
has an unrealistically small focal area.

> Gurth@******.nl - Gurth@***.nl - http://www.xs4all.nl/~gurth/index.html

========================================================================
Adam Getchell "Invincibility is in oneself,
acgetche@****.engr.ucdavis.edu vulnerability in the opponent."
http://instruction.ucdavis.edu/html/Adam/getchell.html
Message no. 12
From: Adam Getchell <acgetche@****.UCDAVIS.EDU>
Subject: Re: jamming laser communications
Date: Mon, 6 Mar 1995 09:43:17 -0800
On Fri, 3 Mar 1995, Sam Thomas wrote:

> You might want to pay the crypto areas of internet. The Puzzle Place can and

You might want to pay attention to Scientific American, October
1994 "Quantum Cryptography".
As Stainless Steel Rat can verify to you, the Vernan cipher is
fundamentally unbreakable. No amount of processing can crack it. It
requires a random key as long as the encrypted message, however.
The random numbers can be gotten from natural noise data.
If you want details, I can try to dig up my old messages to
e-mail you. Or you can check the above reference.

> Sinbad Sam

========================================================================
Adam Getchell "Invincibility is in oneself,
acgetche@****.engr.ucdavis.edu vulnerability in the opponent."
http://instruction.ucdavis.edu/html/Adam/getchell.html
Message no. 13
From: Marc A Renouf <jormung@*****.UMICH.EDU>
Subject: Re: jamming laser communications
Date: Mon, 6 Mar 1995 15:42:18 -0500
On Sat, 4 Mar 1995, Gurth wrote:

> I still believe you
> can jam the receiver by shining a laser into it... I didn't really
> understand all of Adam's reasoning (never paid much attention in physics
> class, thanks to my "very entertaining" (more like the opposite) teacher),
> but my reasoning is as follows: if the receiver is set up for a certain
> frequency of laser, you could use the same frequency laser to blind it, in
> that way the actual transmitter would not be noticed because the receiver is
> continually illuminated by the jammer...

There is an easier way to "jam" laser communications. It's an
easy three-step process.
1. Get a HARM (High-speed Anti Radiation Missile for those of
you who are militarily challenged :) )

2. Reconfigure the seeker head to home on laser designator
signals that just happen to be the same wavelength as what your enemy is
using to transmit with.

3. Fire the HARM and watch the fireworks. You see, as Adam's
post pointed out, the longer range communications will experience
dispersion and scattering that will make the laser "beam" anywhere from
0.5 to 10 meters in diameter depending on the range between transmitter
and reciever. The HARM homes in on the laser signal that is scattered
back from things around the receiver. Hence, your enemy's own comm
system becomes the laser designator for your missile. Not terribly
accurate, but it would probably get the job done. Fun, neh?

Actually, upon further reflection, you may want to use a missile
capable of deploying cluster munitions to saturate the area (10 meters
radius is a little big for a HARM). Or maybe laser-guided bombs for
hardened targets like comm bunkers, etc.

Marc
Message no. 14
From: Robert Watkins <bob@**.NTU.EDU.AU>
Subject: Re: jamming laser communications
Date: Tue, 7 Mar 1995 14:08:09 +0930
Marc A Renouf wrote:
>
> There is an easier way to "jam" laser communications. It's an
> easy three-step process.
> 1. Get a HARM (High-speed Anti Radiation Missile for those of
> you who are militarily challenged :) )
>
> 2. Reconfigure the seeker head to home on laser designator
> signals that just happen to be the same wavelength as what your enemy is
> using to transmit with.
>

Uh, gee, Rocky, what does "frequency-agile transmitters" mean?

> 3. Fire the HARM and watch the fireworks. You see, as Adam's
> post pointed out, the longer range communications will experience
> dispersion and scattering that will make the laser "beam" anywhere from
> 0.5 to 10 meters in diameter depending on the range between transmitter
> and reciever. The HARM homes in on the laser signal that is scattered
> back from things around the receiver. Hence, your enemy's own comm
> system becomes the laser designator for your missile. Not terribly
> accurate, but it would probably get the job done. Fun, neh?
>

Nope...

--
Robert Watkins bob@**.ntu.edu.au
Real Programmers never work 9 to 5. If any real programmers
are around at 9 am, it's because they were up all night.
Finger me for my geek code
Message no. 15
From: Jason Larke <jlarke@**.ITD.UMICH.EDU>
Subject: Re: jamming laser communications
Date: Tue, 7 Mar 1995 00:26:21 -0500
In message <199503070438.OAA10516@*******.cs.ntu.edu.au>you write:
>Marc A Renouf wrote:
>>
>> 2. Reconfigure the seeker head to home on laser designator
>> signals that just happen to be the same wavelength as what your enemy is
>> using to transmit with.
>>
>
>Uh, gee, Rocky, what does "frequency-agile transmitters" mean?

In the case of lasers, I didn't think such things were practical
in the field. The wavelength of a laser is, after all, a function
of the gas/whatever being stimulated. In all the fiction I've
read, tunable lasers were big an less efficient, pound per pound.

But I could be wrong. :)

------
Jason Larke- jlarke@*****.edu- sysadmin, philosophy guy, and Rush fan
"I drink the blood of my enemies," Hawk said, and smiled his happy grin."
I don't speak for ITD-LSA, U-M, or the international communist conspiracy.
Send mail for PGP public key.
Message no. 16
From: Paul Finch <pfinch@****.EDU>
Subject: Re: jamming laser communications
Date: Mon, 6 Mar 1995 22:55:06 -0700
On Tue, 7 Mar 1995, Jason Larke wrote:

> In message <199503070438.OAA10516@*******.cs.ntu.edu.au>you write:
> >Marc A Renouf wrote:
> >>
> >> 2. Reconfigure the seeker head to home on laser designator
> >> signals that just happen to be the same wavelength as what your enemy is
> >> using to transmit with.
> >>
> >
> >Uh, gee, Rocky, what does "frequency-agile transmitters" mean?
>
> In the case of lasers, I didn't think such things were practical
> in the field. The wavelength of a laser is, after all, a function
> of the gas/whatever being stimulated. In all the fiction I've
> read, tunable lasers were big an less efficient, pound per pound.
>
> But I could be wrong. :)


What about pulse doppler laser beams, like in the War of the Chtorr by
David whats his name? Didnt they use a laser that hopped freaqs or some
such?

Edge
Message no. 17
From: Robert Watkins <bob@**.NTU.EDU.AU>
Subject: Re: jamming laser communications
Date: Tue, 7 Mar 1995 15:47:40 +0930
Jason Larke wrote:
>
> >Uh, gee, Rocky, what does "frequency-agile transmitters" mean?
>
> In the case of lasers, I didn't think such things were practical
> in the field. The wavelength of a laser is, after all, a function
> of the gas/whatever being stimulated. In all the fiction I've
> read, tunable lasers were big an less efficient, pound per pound.
>
> But I could be wrong. :)

Well, that's true with chemical lasers. But, as I understand it, the most
practical type is a "free-electron" laser, which are readily tuned.

Let me assure you of one thing. If it was so easy to use HARM missiles to
take out laser transmitters, then people wouldn't use laser transmitters.
As people do, obviously HARM missiles can't readily take out laser
transmitters. QED.

--
Robert Watkins bob@**.ntu.edu.au
Real Programmers never work 9 to 5. If any real programmers
are around at 9 am, it's because they were up all night.
Finger me for my geek code
Message no. 18
From: Gurth <gurth@******.NL>
Subject: Re: jamming laser communications
Date: Tue, 7 Mar 1995 12:13:09 +0100
> There is an easier way to "jam" laser communications. It's an
>easy three-step process.

[proces deleted]

> Actually, upon further reflection, you may want to use a missile
>capable of deploying cluster munitions to saturate the area (10 meters
>radius is a little big for a HARM). Or maybe laser-guided bombs for
>hardened targets like comm bunkers, etc.

Just use a Hellfire instead -- no messing with changing seeker heads, just
set it to home on the frequency used by the transmitter.
But I think people will start making comments about this, so I'll be one
step ahead and make them myself :)
1) you need to know the frequency used by the transmitter otherwise the
missile won't home in on the receiver.
2) if they use burst transmissions the signal is gone before you have time
to launch your missile
3) you still need to know the approximate location of the receiver because
of the limited area the missile's seeker scans for the target pointer
4) there'll be more, but I can't think of them immediately :)


Gurth@******.nl - Gurth@***.nl - http://www.xs4all.nl/~gurth/index.html
And it rips my life away... But it's a great escape...
Geek Code v2.1: GS/AT/! -d+ H s:- !g p?(3) !au a>? w+(+++) v*(---) C+(++) U
P? !L !3 E? N++ K- W+ -po+(po) Y+ t(+) 5 !j R+(++)>+++$ tv+(++) b+@ D+(++)
B? e+ u+@ h! f--(?) !r(--)(*) n---->!n y?
Message no. 19
From: pran r mukherjee <pran@*****.UMICH.EDU>
Subject: Re: jamming laser communications
Date: Tue, 7 Mar 1995 16:06:49 -0400
On Tue, 7 Mar 1995, Robert Watkins wrote:

> Jason Larke wrote:
> >
> > >Uh, gee, Rocky, what does "frequency-agile transmitters" mean?
> >
> > In the case of lasers, I didn't think such things were practical
> > in the field. The wavelength of a laser is, after all, a function
> > of the gas/whatever being stimulated. In all the fiction I've
> > read, tunable lasers were big an less efficient, pound per pound.
> >
> > But I could be wrong. :)
>
> Well, that's true with chemical lasers. But, as I understand it, the most
> practical type is a "free-electron" laser, which are readily tuned.
>
> Let me assure you of one thing. If it was so easy to use HARM missiles to
> take out laser transmitters, then people wouldn't use laser transmitters.
> As people do, obviously HARM missiles can't readily take out laser
> transmitters. QED.
>

Do you really think it's that easy to GET a HARM missile?
Message no. 20
From: Adam Getchell <acgetche@****.UCDAVIS.EDU>
Subject: Re: jamming laser communications
Date: Tue, 7 Mar 1995 14:45:39 -0800
On Tue, 7 Mar 1995, Robert Watkins wrote:

> Let me assure you of one thing. If it was so easy to use HARM missiles to
> take out laser transmitters, then people wouldn't use laser transmitters.
> As people do, obviously HARM missiles can't readily take out laser
> transmitters. QED.

Actually, the new HARM II has this neat feature called "Target
Memory". When the seeker loses track of the emitter, the missile
calculates the last position of the emitter and homes on that location.
As for how accurate this is, quite a few Iraqi Radar stations
were destroyed by HARMs, despite the fact they shut off.
The other nice thing about HARM is that it scans a large range of
frequencies, using the very same technology that "frequency agile"
transmitters do. Specifically, in the case of a free electron laser
there is a specified range of frequencies it is limited to. A HARM
missile could be programmed to scan for these.
Finally, the U.S. has the luxury of using certain technologies
(our spiffy radars and lasers and such) because we don't account for
technologically equivalent foes. This kind of thinking often gets us in
trouble when Australian surface groups sneak up on our carriers by
maintaining strict electronics silence ("Southern Cross '85"), or when
(West) German artillery drops 30 155mm shells on our CP because the C.O.
forgot to cease transmitting.
The old Soviet army didn't have too many HARMs ...

> Robert Watkins bob@**.ntu.edu.au

========================================================================
Adam Getchell "Invincibility is in oneself,
acgetche@****.engr.ucdavis.edu vulnerability in the opponent."
http://instruction.ucdavis.edu/html/Adam/getchell.html

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These messages were posted a long time ago on a mailing list far, far away. The copyright to their contents probably lies with the original authors of the individual messages, but since they were published in an electronic forum that anyone could subscribe to, and the logs were available to subscribers and most likely non-subscribers as well, it's felt that re-publishing them here is a kind of public service.

Thwap!