Defense against UAV's

wrote:
Jeb wrote:
wrote:

The problem here is that it could be a kind of 'asymmetric warfare', in
that the costs and problems of the defence are potentially far more
costly than those of the attackers.

It would seem to me to be likely that a simple software code
modification would allow an Aegis system to detect smaller, slower
returns (I would expect that right now, those get filtered out so that
seabirds don't cause spurious readings on the radar scopes). If you
pick up a weak signal that doesn't belong there, just have AEGIS dump
all of its radiating power down a relatively tight beam and zorch a
little lightweight unshielded UAV right out of its electronic mind.

Shielding agains nuclear EMP might be tough (especially because it is
so non-trivial to check whether it works).

Shielding against a radar with known properties should not be a
problem. If you go to the pains of designing and building the UAVs, you
don't leave them vulnerable against such an obvious way to deal with
them.

If you say so. But how much weight do you think you'll have to add
to that "cheap and simple" UAV to keep a CG or DDG's AN/SPY-1 from
burning out the electronics from sheer power output alone? Suddenly
the cost and complexity aspect of those UAVs is going to go way up and
result in either a smaller unit buy or the buyers spending a lot more
on those UAVs than they'd planned.

For that matter, if you can locate the UAV by radar, then just direct a
blinding laser against the system so that either it can't target or
can't feed useful info back to its controller. Takes it out of the
mission and still doesn't require expenditure of any ordnance, if the
targeted ship doesn't want to kill it.

wrote in message
oups.com...

Keith W wrote:
If you are using video imaging (backed up by some other, e.g.
IR/passive EM sensors),
I suspect it is a graduate student's exercise in image recognition to
distinguish a warship (esp. aircraft carrier) from an oil
rig/tanker/finshing ship. Especially if you are flying slow.

As a software engineer I'd suggest you are wrong. If such recognition
is so easy how did an Argentine aircrew drop bombs on an
American tanker in 1982 believing it was a RN Carrier ?


Scared ****less of being shot down?

The Argentine air crews displayed almost suicidal bravery

Wishful thinking?
Orgasmic about being able to release their weapons and claim kills?
Darkness/lousy weather/bad visibility?

Daylight

Flying fast and having only few short seconds to make decision?

In a C-130 ?

Releasing their weapons from way too far range for positive
identification (perhaps because being scared ****less)?

They rolled them off the exit ramp at mast top height


Can be any of these or their combination.


Or just maybe its harder than you think.

A UAV with realtime video image recognition and IR sensors is unlikely
to be especially cheap
Realtime video image recognition needs a source of video (probably a
wide-angle search camera + narrow angle scope with some decent
magnification for examining the suspicios contacts),

Problem 1 ) You have to process them to decide if they are suspicious


a decent CPU to do
the number crunching and a software to do the analysis. The first two
items are not particularly expensive. The software might take real
pains to develop, but afterwards the copies are free.

Understatement of the year

Perhaps the
costliest part of the development would be sea trials (to see how is
the real-time identification working and debug it), but then who knows
what they use their small UAVs for now (see the first message of this
thread).


Who knows if the incident even happened.

snip
200 km/hr UAV's are going to be rather vulnerable to all forms
of active defence including point defence missiles like RAM
and to CIWS.
Yes. That's why you want them to be really cheap and use swarming.

With real time image recognition systens cheap will be quite a trick.
The cost might be high for initial development, but there is not reason
the cost should be high on per-unit base. Cameras/CPUs and copying
software is cheap. Cooled IR sensors and other fancy sensor stuff might
rise the cost - the question is how much of it is needed, especially
if you don't ask for all-weather capability.

All of it or it wont work




On
the other hand RAM is IR homing and the IR signature of a 100hp piston
engine is negligible compared to the IR signature of a rocket/jet
engine of the current antiship missiles.
But not small enough to be invisible
Nothing is invisible. But if its signature is there with seagulls and
sun reflections off waves, the locking/homing task is so much harder.


Seagulls dont have 100 hp engines. Even cheap IR sensors
have no problem with people let alone IC engines

Phalanx (or other gun-based CIWS) should be effective, but has rather
short range (and not THAT much reloads, if you are dealing with a huge
swarm). I suspect it is also looking at targets with much higher radar
signature and very different characteristics.

Thats just software and rather easier to do than deciding if
that 1000 ft long ship is a carrier or VLCC
An attacking UAV can make its decision to attack close enough - when it
can actually see the island/aircrafts on deck of the carrier.

First it has to decide to get close enough, then it has to survive
the transit

And has a
lots of frames to base its decision on. It might even send some info to
the controller and ask whether to attack or not (again, tradeoff
between how much you send and how reliable you want your communication
channel to be).


Comms are BAD things for an autonomous UAV , they can be jammed



The CIWS mounts look rather distinctly and will obviously be among the
targeted areas of the ship. You don't need that much of a warhead to
put CIWS radar ot of commission - so perhaps an UAV with 200kg warhead
can actually carry 8-12 short range missiles designed for homing on
CIWS radar and launch them while being out of range of CIWS.


Earth Calling Planet Esteban - a UAV with 200kg warhead and
8-12 sub missiles will be neither small nor cheap.
Such an UAV will not be small: it will be Predator size, powered by a
Rotax, Jabiru or more likely cheap copy of them.


None of which carry 8-12 sub missiles. Note that controlling
Predator involves 3 operators in a 30ft trailer packed with electronics

But it can be cheap,
especially if mass produced and intended for one-way cruise-missile
type missions.

Not with the abilities you are demanding.

Ultralight aircraft kits are essentially hand-made and
sell for 10-20k.

Indeed but of course they fly a around 70 knots
with a max gross weight of around 300 kg, not
much room there for 200kg warheads

Replace the cabin with the warhead(s), give it faster
wing (no need for low stall speed, this is on one way mission) and the
sensors/brains/communication kit and mass produce it.

Real easy huh , when do you plan to start production ?

Be smart
designing it (ease of mass production) and try to reduce the IR/radar
signature, but don't go overboard with that - keep the costs down. The
only potentially expensive parts on the aircraft are sensors and
warheads. The 200kg is the total useful load, some UAVs will have it
divided as sub missiles for massed attack on air defense radars, other
UAVs will simply have a big explosive load (hoping that the radars have
already been damaged, so they can get in close to do BAM).

...
simple systems are easier to debug/design correctly). However, a
country like China/India or even Iran should be able to mass produce
good enough UAVs for peanuts (i.e be able to field thousands of them).
The key term being 'good enough', not 'super duper, all weather, high
reliability and long service life'.

But with real time image recognition, organic SEAD and large warheads
Yeah, you need real time image recognition. That is the enabling
technology. I think we can agree to disagree whether that is possible
in the next 5-10 years, for operation in good visibility.

The quoted 200kg was just quoted as an example - about what an
ultralight aircraft can carry. You need your aircraft big enough to
have enough range to engage the carrier group operating off your
shores, so a 200kg payload will not significantly increase it anyway.
A modified ultralight can't fly that fast, leaving it rather
vulnerable.


I think I already said that

That's why you are better of launching submunitions from
out of range of the gun CIWS. Those subminitions need to be reasonably
smart (once qued by the sensors of the main craft, they need to be able
to lock on their target and hit it), but not necessarily pack a lot of
punch (hitting radars, aircraft on deck and so on).

Hint CIWS reach a long way , the sort of missile you'd need would
be stinger sized at a minimum and you need a control system
smart enough to know WHEN to fire, sensor fuzion is harder than
you seem to think

Once the radars
have been damaged, the second wave can then just press on with large
warhead bringing general destruction. (Or, to keep it simple, they all
go together. If the radars are switched off, the large warheads will
arrive and do the damage, if the radars are on (likely), the
submunitions will home on them.)


So you now rely on a new development of small fast radar
homing sub munitions as well, and all this a grad student
technology , yeah right !

Keith

"Keith W" wrote in message
...

wrote in message
oups.com...

Keith W wrote:
If you are using video imaging (backed up by some other, e.g.
IR/passive EM sensors),
I suspect it is a graduate student's exercise in image recognition to
distinguish a warship (esp. aircraft carrier) from an oil
rig/tanker/finshing ship. Especially if you are flying slow.

As a software engineer I'd suggest you are wrong. If such recognition
is so easy how did an Argentine aircrew drop bombs on an
American tanker in 1982 believing it was a RN Carrier ?


Scared ****less of being shot down?

The Argentine air crews displayed almost suicidal bravery

Are these exclusive?

Glenn D.

"Glenn Dowdy" wrote in message
...

"Keith W" wrote in message
...

wrote in message
oups.com...

Keith W wrote:
If you are using video imaging (backed up by some other, e.g.
IR/passive EM sensors),
I suspect it is a graduate student's exercise in image recognition to
distinguish a warship (esp. aircraft carrier) from an oil
rig/tanker/finshing ship. Especially if you are flying slow.

As a software engineer I'd suggest you are wrong. If such recognition
is so easy how did an Argentine aircrew drop bombs on an
American tanker in 1982 believing it was a RN Carrier ?


Scared ****less of being shot down?

The Argentine air crews displayed almost suicidal bravery

Are these exclusive?


Not at all

Keith

In article .com,
says...

Andrew Swallow wrote:

Many UAVs are flown under remote control. Radio direction finding may
permit the location of its headquarters to be found.

Good point, few countries have enough satellite bandwidth to manage
UAVs the way the US does, so unless Iran is buying bandwidth from
someone else, they'd have to be RC controlled UAVs.

Fully autonomous UAVs are not common today---but they probably will
be in another few years. They would be particularly good
for surveillance of large targets like a CVBG. The UAV could
send out data and wait for very generic microburst commands
like "circle left, 20mile radius". That would make it hard
to attack the controller. While it may be possible get a DF
location on a randomly-timed, 10millisecond, spread spectrum signal
from a mobile command post, it might also be very expensive.


That would make the controller VERY vulnerable to counter fire and
would severly limit range. It would also make the control of the UAV
somewhat easy to jam, or even commandeer.

I would expect that military UAVs would have fairly good encryption
on the links. Heck, even the low-cost ($179) 900 MHz modems we use
on some projects feature frequency hopping and 256-bit AES encryption.

http://www.maxstream.net/products/xt...odem-rs232.php

Mark Borgerson

wrote in message
oups.com...
wrote:

An Iranian UAV was able to circle a U.S. aircraft carrier undetected
for 25 minutes.

How can we protect our forces against UAV's when other countries or
terrorist
organizations start using them against us?

Carrier launches it's own swarm of 1/6 scale Hellcats to cut the
intruders' crepe-paper streamers with their props...

Finally someone's thinking straight. Personally I'd forget all the high-tech
stuff and go for an old WWII carrier with Seafires on it. No swarm of UAVs
can match that, plus all the WWII pilot wanabees get to fly. If a flight is
sent to intercept a flock of birds, oh well, at least they've flown. If they
come across hostile UAVs its time to check the lightbulb in that good old
reflector gunsight and go weapons hot.

In article . com,
says...

wrote:
Jack Linthicum wrote:
wrote:

If the report on the Iran UAV is accurate, the USN is evidently not on
top of this at present. I hope they are working on it, very hard.

Like anti-radiation missiles. Against the launch sites and control
points.

Since only a simple radio signal is needed to control the UAVs (and
then not all of the time - only when they want to instruct them to do
something) that would be very much harder than hitting a high-powered
radar which has to keep transmitting a distinctive signal all of the
time to do its job. And AR missiles could easily be decoyed by lots of
cheap radio transmitters scattered about.

The problem here is that it could be a kind of 'asymmetric warfare', in
that the costs and problems of the defence are potentially far more
costly than those of the attackers.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk

The mention was of swarms which implies swarms of signals which then
implies if I have an ECM craft up and I get lots of radiation from one
direction I will send a message to that source. The decoys may work the
second time but not the first or third. The control point will be that,
singular, one command directing all of the UAVs from one spot. How many
generals would you trust if you were Mahmoud Ahmadinejad?

One control point for a swarm of semi-intelligent UAVs does not imply
either continuous transmission or a single transmitter.

Mark Borgerson

In article .com,
says...

wrote:
Jack Linthicum wrote:
...
The mention was of swarms which implies swarms of signals
not necessarily, if mostly autonomous UAVs are used

which then implies if I have an ECM craft up and I get lots of radiation from one
direction I will send a message to that source. The decoys may work the
second time but not the first or third.
??

The control point will be that, singular, one command directing all of the UAVs
from one spot.
Ever heard of fiber optics communications? Set-up multiple cheap
antennas for communication, and link them with fiber optics to your
safe hidden command centre. Why you guys always assume that the bad
boys are dumb beyond recognition alludes me...

What the hell is an autonomous UAV?

Well, a semi-autonomous UAV is one that doesn't require continuous
flight-control command. It simply requires comms more on the order
of those with a fighter pilot: "Target in sight" "cleared to fire",
etc.

and to what purpose? You need a
unique signal for each aircraft otherwise they will all turn left at
the same time.

Nope. You just need a different packet address for each UAV.


On the first shot you may hit a bunch of decoys but also
the target or targets. Especially if the decoys must be deployed under
the control of the central command. Second time the decoys may stay on
and the command freqs shut down. Third time no one cares and fires
enough weapons to take care of the site and the decoys.

How many rounds does the defense need to destroy all those decoys
and targets?

I have heard of fiber optic communications, those antennas will still
radiate and believe it or not the U.S. military can figure out where
the command point is physically. The bad guys do not have to be smart
or dumb, they will be overwhelmed by the amount of crap the U.S. can
throw at tem. It's the occupation afterwards that is the sticking point.

Yup. Then the US military will be overwhelmed by the amount of
crap the insurgents throw at them! ;-( The guys on land are having
problems countering modest numbers of low-cost, command detonated
munitions. The Navy has the advantage of greater standoff range--
but loses a lot of that advantage as soon as it comes time to
put boots on the beach.


Mark Borgerson

Keith W wrote:

Can be any of these or their combination.
Or just maybe its harder than you think.
Somehow I doubt when they were overflying the tanker in daylight, they
still thought they are attacking an aircraft carrier. :-)

A UAV with realtime video image recognition and IR sensors is unlikely
to be especially cheap
Realtime video image recognition needs a source of video (probably a
wide-angle search camera + narrow angle scope with some decent
magnification for examining the suspicios contacts),

Problem 1 ) You have to process them to decide if they are suspicious
There are not so many big things floating in the ocean, just examine
them all.
While the waves move and provide clutter, in half-decent weather a
100m+ ship tends to stick out as a sore thumb from quite afar. And it
is quite unlikely there will be third party merchants sticking around a
US carrier group in time of armed conflict....

a decent CPU to do
the number crunching and a software to do the analysis. The first two
items are not particularly expensive. The software might take real
pains to develop, but afterwards the copies are free.
Understatement of the year
Yes, if you want to be able to do it in all weather, from 50km+ afar,
your target hidden among the merchants, in few moments of ultrasonic
flight.

In fair weather, from less then 15km, with closing speed of 200km/h, I
am not so sure. Warships do look quite differently then merchants/oil
rigs, and they also tend to radiate differently.

With real time image recognition systens cheap will be quite a trick.
The cost might be high for initial development, but there is not reason
the cost should be high on per-unit base. Cameras/CPUs and copying
software is cheap. Cooled IR sensors and other fancy sensor stuff might
rise the cost - the question is how much of it is needed, especially
if you don't ask for all-weather capability.

All of it or it wont work
See above. Fair weather, no clutter. You want sensors from different
spectra to work together, but they can be the cheap stuff...

On
the other hand RAM is IR homing and the IR signature of a 100hp piston
engine is negligible compared to the IR signature of a rocket/jet
engine of the current antiship missiles.
But not small enough to be invisible
Nothing is invisible. But if its signature is there with seagulls and
sun reflections off waves, the locking/homing task is so much harder.

Seagulls dont have 100 hp engines. Even cheap IR sensors
have no problem with people let alone IC engines
With the engine tucked at the back (like Predator) and with good mixing
of the exhaust gas, you are mostly looking at cold front face.
Seagulls/people tend to present warm bodies.

Moreover, those cheap sensors are not mounted on supersonic missiles
screaming to intercept you (the heat of the supersonic air alone might
wash out your meager IR signature).

Phalanx (or other gun-based CIWS) should be effective, but has rather
short range (and not THAT much reloads, if you are dealing with a huge
swarm). I suspect it is also looking at targets with much higher radar
signature and very different characteristics.

Thats just software and rather easier to do than deciding if
that 1000 ft long ship is a carrier or VLCC
An attacking UAV can make its decision to attack close enough - when it
can actually see the island/aircrafts on deck of the carrier.

First it has to decide to get close enough, then it has to survive
the transit
First is not that tough - with enough endurance reserve. Second is the
matter of identification distance. And if the suspected target is
illuminating me with targetting radar, I don't really have problem to
identify it as a target, even if I am relatively far.

And has a
lots of frames to base its decision on. It might even send some info to
the controller and ask whether to attack or not (again, tradeoff
between how much you send and how reliable you want your communication
channel to be).
Comms are BAD things for an autonomous UAV , they can be jammed
Yes - but low bandwith intelligently designed comms are tough to jam.

Earth Calling Planet Esteban - a UAV with 200kg warhead and
8-12 sub missiles will be neither small nor cheap.
Such an UAV will not be small: it will be Predator size, powered by a
Rotax, Jabiru or more likely cheap copy of them.
None of which carry 8-12 sub missiles.
Useful load of Predator is about thousand pounds. A hellfire is more
useful for predator then 8-12 short range anti-radar missiles.

Note that controlling
Predator involves 3 operators in a 30ft trailer packed with electronics
Predator does a lot more, and the operators/electronics are there to
analyze/evaluate what it sees, in a much harder to analyze environment,
and with much higher expectations.

Ultralight aircraft kits are essentially hand-made and
sell for 10-20k.

Indeed but of course they fly a around 70 knots
with a max gross weight of around 300 kg, not
much room there for 200kg warheads
Ultralights with 100hp engines are limited to cca 500kg and 100knots by
law, not by physics. Predator uses the same 100hp Rotax and has 220km/h
max speed, around 1000kg takeoff weight of which cca 500kg is dry
weight (200payload, 300 fuel).
That 500kg of dry weight also includes lots of sensors you will do
without.

Replace the cabin with the warhead(s), give it faster
wing (no need for low stall speed, this is on one way mission) and the
sensors/brains/communication kit and mass produce it.

Real easy huh , when do you plan to start production ?
The tough part is really the sensors/data analysis, not the
airframe....


That's why you are better of launching submunitions from
out of range of the gun CIWS. Those subminitions need to be reasonably
smart (once qued by the sensors of the main craft, they need to be able
to lock on their target and hit it), but not necessarily pack a lot of
punch (hitting radars, aircraft on deck and so on).

Hint CIWS reach a long way , the sort of missile you'd need would
be stinger sized at a minimum and you need a control system
smart enough to know WHEN to fire, sensor fuzion is harder than
you seem to think
Stinger missile proper weights 10kg, plenty of room in my 200kg
allowance for 8 of them.

Somehow identifying the range to the target (when you are within line
of sight and less then 10km away) does not seem too hard to me.

Knowing that I am being illuminated by targeting radars also helps in
making my decision.

Once the radars
have been damaged, the second wave can then just press on with large
warhead bringing general destruction. (Or, to keep it simple, they all
go together. If the radars are switched off, the large warheads will
arrive and do the damage, if the radars are on (likely), the
submunitions will home on them.)
So you now rely on a new development of small fast radar
homing sub munitions as well, and all this a grad student
technology , yeah right !
No, being India/China/Iran, I already have those - maybe a bit larger,
but no significant new development needed.

Keith

Jack Linthicum wrote:
Mark Borgerson wrote:
In article . com,
says...

wrote:
Jack Linthicum wrote:
wrote:

If the report on the Iran UAV is accurate, the USN is evidently not on
top of this at present. I hope they are working on it, very hard.

Like anti-radiation missiles. Against the launch sites and control
points.

Since only a simple radio signal is needed to control the UAVs (and
then not all of the time - only when they want to instruct them to do
something) that would be very much harder than hitting a high-powered
radar which has to keep transmitting a distinctive signal all of the
time to do its job. And AR missiles could easily be decoyed by lots of
cheap radio transmitters scattered about.

The problem here is that it could be a kind of 'asymmetric warfare', in
that the costs and problems of the defence are potentially far more
costly than those of the attackers.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk

The mention was of swarms which implies swarms of signals which then
implies if I have an ECM craft up and I get lots of radiation from one
direction I will send a message to that source. The decoys may work the
second time but not the first or third. The control point will be that,
singular, one command directing all of the UAVs from one spot. How many
generals would you trust if you were Mahmoud Ahmadinejad?

One control point for a swarm of semi-intelligent UAVs does not imply
either continuous transmission or a single transmitter.

Mark Borgerson

I think that a spread spectrum burst type transmission can be
intercepted and given a rough bearing. The money to do this is
miniscule in comparison with making Trident missiles into hand
grenades.
Hm, I don't know. Especially if they employ hundreds/thousands of
battery/solar powered decoy transmitters. You will need to listen on
the whole spectrum, all time, and be able to sort out what is real and
what is noise.

Still have to transmit to the aircraft, whether it is a high
sophisticated address or not the transmission has to be made to each
aircraft.
No, a broadcast to the whole group is enough.

Home on radiation.
The radiation is almost never there (short bursts from different
locations). You will need to remember the bearing/location of the
burst, then examine that neighbourhood for anything suspicious and then
perhaps attack it. With decoy transmitters .... good luck!

Again the idea that the position in which
a large scale use of UAVs is analogous to the IED situation is not
defensible. Multiple targets are multiple targets to an airborne
system. So far I see this whole discussion as one of a possible but not
probable situation.
Tough to say what is probable. What is certain is that the potential
adversaries are not stupid, and they are searching assymetric ways how
to neutralise the US military advantages....