NationStates Jolt Archive

Is millimeter wavelength viable as radar and why? I see many PMT nations using them in their military and frankly, I don't see why anyone would choose to use millimeter wavelengths for missile guidance or any purpose whatever. Can anyone fill me in why anyone would use this for a military application?

Is millimeter wavelength viable as radar and why? I see many PMT nations using them in their military and frankly, I don't see why anyone would choose to use millimeter wavelengths for missile guidance or any purpose whatever. Can anyone fill me in why anyone would use this for a military application?

Well off the top of my head the usage of millimetric wave radars is down solely to the Apatche longbow and the longbow hellfire ATGMs plus possibly the brimstone ATGM.

various tank active protection systems have mentioned millimetric radars so i assume it provides a secondary source of inspiration

A shorter wavelength increases resolution, so it is employed where a radar is needed that can filter out clutter. Usually this is when tracking fairly small objects close to the ground. It isn't PMT - it exists in real life.

A shorter wavelength increases resolution, so it is employed where a radar is needed that can filter out clutter. Usually this is when tracking fairly small objects close to the ground. It isn't PMT - it exists in real life.

Though it has a very very short range and its inabilities prevent it from becoming capable of being used in missiles though for the very purpose of range. Much less useful as a radar station. Anyone who argues this doesn't know that it is not meant nor wise to see its unable to function as anything higher then collision avoidance (not necessary at all) on the battlefield?

It's quite useful for ATGM guidance, actually. Depending on cloud cover, the Longbow Hellfire has a range of about nine kilometers, which is more than enough for it's role. It'd also be excellent for detecting incoming threats for a tank's APS.

Though it has a very very short range and its inabilities prevent it from becoming capable of being used in missiles though for the very purpose of range. Much less useful as a radar station. Anyone who argues this doesn't know that it is not meant nor wise to see its unable to function as anything higher then collision avoidance (not necessary at all) on the battlefield?

Strictly speaking it does have a use in CAS-role vehicles, be they ground, fling-wing or fixed-wing. Close up, it can distinguish shapes easily, so could be used as a fire-control and short-range guidance system. Over long distances, such as long-range SAM or search radars, true, longer wavelengths are better, but to say it's only good as collision avoidance is, frankly, rubbish.

Though it has a very very short range and its inabilities prevent it from becoming capable of being used in missiles though for the very purpose of range. Much less useful as a radar station. Anyone who argues this doesn't know that it is not meant nor wise to see its unable to function as anything higher then collision avoidance (not necessary at all) on the battlefield?

Well, AFAIK most people who use millimeter wave radar use it on vehicles and on short-range missiles (a.k.a Hellfire). Not on everything. AESA is more overused than millimeter wave radar.

Why not just use sub-millimeter systems? Strictly speaking that is a better option then millimeter radar with the ability to back up for all other systems and not act like a microwave. So the range is more to traditional radar then other systems. It seems like the logical choice. I don't see why anyone (tanks should use sub-milli as well) would even want to use mm radar anymore.

Is millimeter wavelength viable as radar and why? I see many PMT nations using them in their military and frankly, I don't see why anyone would choose to use millimeter wavelengths for missile guidance or any purpose whatever. Can anyone fill me in why anyone would use this for a military application?

Precision.

Millimeter waves may not have range, but they can spot things that a longwave (up to 4 meters) 'search' radar could miss.

In simple terms, a WW2 shore based longwave radar was lucky to guide a plane within 2 km of another enemy plane.

A shortwave radar, can get within 10 meters.

And MMWR can get within 1 meter...

Millimeter wave and microwave radar are also good because a 'juiced up' model can fry sensitive electronics, or cook your TV dinner, or can be used to search houses from outside without resorting to IIR.

Though it has a very very short range and its inabilities prevent it from becoming capable of being used in missiles though for the very purpose of range. Much less useful as a radar station. Anyone who argues this doesn't know that it is not meant nor wise to see its unable to function as anything higher then collision avoidance (not necessary at all) on the battlefield?
Clearly you should take this argument up with whoever makes the various RL missiles that use MMWR as for their seeker heads.

Hurtful Thoughts....you are confused about the radar. Millimeter is shorter then microwave. The shorter the wave the better for communications and information return. However you have to have a material that does not absorb it to be functional.

One key note is the 340 GHz range. This is not absorbed by the atmosphere or fog or other normal items. So it is infact better then millimeter. This is overall the ideal choice for current means, though I think 580-600 Ghz is another safe band.

The military would be a little surprised to hear me voice my opinions about their technology, but like most things....sub-millimeter systems probably won't be intergrated for another 10-15 years. Traditional means is of a poor signal (which is why millimeter range is bad to begin with) and the generation of millimeter waves results in terrible signal above 190 GHz (I think).

I just think NS nations would be the first to grab sub-millimeter tech, because the overall boost to millimeter radar and even conventional communications systems is a 350% boost to over 4000% boost depending on the systems before. Typical communications are boosted by 400% with sub-millimeter as an increase and bandwidth, but over 4000% boost in range through rain, fog and storms. Things which have plagued the ability of millimeter range radar to surpass even with high Db effectively and cheaply.

It was always this high input, low output, but better return. A key factor of why it was in missiles, but the range was terrible or very expensive (the military went with expensive, but yes 9 Km is bad). Using submillimeter it would not be beyond possible thought to think that the same power can be turned to 80+ Km because of the degradation of the signal is so poor, ultimately giving less demand and far better effectiveness.

Prae...why don't you use sub-millimeter wavelengths?

There is a difference betwen frequency and wavelength, and they do not neesarilly act together.
(Short low frequency for example)

Frequency affects bandwidth, not wavelength.

Though, as stated earlier, millimeter waves (if actually smaller than micro [meter] wavelengths) would be able to pass through things that longer waves would bounce off of.

Downside: more things are radar transparent/absorbent, including some aircraft skins and light fabrics...

Shorter waves also get less interference, however, this interference (or lack of) is the decidng factor in over the horizon radar, limiting MMRW to LOS (sans radar MMRW transparent obstacles) only in most cases, and sometimes, even less... (See mirage/flying dutchman)

Still, MMWR is inherently difficult to decieve with Chaff, making it a really deadly terminal homing radar for missiles.

Your wrong.

Frequency is the number of cycles per second.
Wavelength is the size of the wave.

f = \frac{c}{\lambda}

Wavelength is an inversion to frequency. You can do it by using 1/lambda for frequency. 1/hertz for lambda.

Short wavelengths are not low frequency.

Bandwidth is ultimately based on frequency. The amount of information you can send is limited by frequency. Like in your computer, a faster processer has a higher speed (Ghz). This means that it is ideal to use high frequencies as long as the waves do not get asborbed before reaching the target.

You really need to stop confusing long waves and short waves, because of this you have no idea what you are even talking about. The higher the frequency the shorter the wavelength.

Radio in Kilohertz = long wave
Radio in Mhz = long wave
Microwave (Ghz) = millimeter wave
Sub-millimeter = micrometer range
Infrared = 700 nm+
Visual = Nano meter range (700-400 nm)
UV-A and UV-B = Below 400 nm

As you see the higher the frequency the shorter the wavelength.

So my question still stands, why don't people use the sub-millimeter wavelengths such as 340 Ghz?