New Twist on Bandwidth

Started by Seze Mune, October 12, 2011, 10:16:22 PM

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Seze Mune

Apparently an Italian astrophysicist has figured out a way to tease 100 times more bandwidth out of the existing radio frequencies: twist the little suckers like corkscrews.  This creates multiple subfrequencies which are distinguishable by their amount of twistedness.  According to him, "You can tune the wave with a given frequency as you normally do, but there is also a fingerprint left by the twist," he says.

It was the study of gravity warped by black holes which planted the seed for this new twist on technology.   ;D

Ningey

#1
Do you have any pointers to the theories behind this phenomenon (magazine title(s) and issue number(s), links, etc.)?
I would want to take a look since this would definitely come in handy in hamradio - the frequency allocations sometimes tend to become rather crowded, and if this really works (providing you have the appropriate gear) you could REALLY stuff those bands.

Ever imagined how many hams could do PSK31 in the 80-m-allocation...?

EDIT: Of course, this would pose some questions to be answered:
What would happen if you want to do radio across long distances (like using the sky wave on the HF bands or doing meteor scatter or EME transmissions, or even tropospheric phenomenons), or could you only do this line of sight? Furthermore, would an ordinary antenna and/or transceiver suffice, or would you have to run on more specialized equipment, and what would the power consumption be?


"Sawtute ke tsun nivume - fo ke kerame!"
-- Neytiri te Tskaha Mo'at'ite

"There are two things that are infinite: Human stupidity and the universe. However, I'm not yet sure about the universe."
-- Albert Einstein

"He who gives up freedom for security deserves neither and loses both."
-- Benjamin Franklin

Seze Mune

Nìprrte'.  This was the subject of a recent paper by Italian astrophysicist Fabrizio Tamburini in tandem with Swedish colleague Bo Thidé.  They tested this in Venice in June 2011 and the outcome was apparently successful. Of course, to make this useful for mobile devices we now have to develop antennae which will pick up and transmit these altered waves.

Ningey

Sìltsan. Looks like Google would be an option here to find out more. At least the names should suffice to find anything on this matter.

The reason why I have been asking what happens under certain conditions is that when you use the sky wave for transmission (on the HF bands or even on VHF when you experience Sporadic-E). In that case the polarization is altered to circular no matter what antenna you are using.
In that case, what happens to those twisted waves? Do they retain their twist pattern, or is that lost once polarization changes (in other words: the sky wave - and thus long skips - would be useless)?


"Sawtute ke tsun nivume - fo ke kerame!"
-- Neytiri te Tskaha Mo'at'ite

"There are two things that are infinite: Human stupidity and the universe. However, I'm not yet sure about the universe."
-- Albert Einstein

"He who gives up freedom for security deserves neither and loses both."
-- Benjamin Franklin

Seze Mune

The Sporadic-E sounds like an e-wormhole so to speak. This is very interesting. 

I've read that the full moon increases the negative ionization of the atmosphere.  If that true (big IF) I would imagine there would be a perceptible change in radio wave propagation then.

Ningey

#5
Quote from: Seze Mune on October 13, 2011, 10:49:04 PM
The Sporadic-E sounds like an e-wormhole so to speak. This is very interesting. 

I've read that the full moon increases the negative ionization of the atmosphere.  If that true (big IF) I would imagine there would be a perceptible change in radio wave propagation then.

Kehe. That's not a wormhole, occasionally the E layer manages to simply bounce VHF (and maybe even UHF) signals back to the ground so that the sky wave becomes available even on those bands. Since the word "sporadic" is part of the description, you cannot tell when or where such highly ionized areas happen to form. However, you will notice that you are dealing with this phenomenon when suddenly DX transmissions (i. e. 500+ km on VHF and UHF) become possible.

And as far as the ionization of the atmosphere is concerned, the most important factor is the sun. That's why you cannot do DX calls during daylight hours on MF or below, and even the long wave bands in the HF segment are closed (the D layer simply absorbs the radio waves), but tend to open up during nighttime when the D layer dissipates.
The contrary is true on the short wave bands in the HF segment (and even on the long wave segments in the VHF band) during daytime, with the bands opening for DX during daylight hours and being closed during nighttime, with best results near sunspot maximum and during summertime, when the F2 layer is at its peak intensity. You may even experience short skips on that occasion (i. e. the sky wave returning to ground well short of 500 km from its origin).
In how far the full moon really has an impact I cannot tell - but if, it is marginal and of no relevance for DX propagation.

BTT: No matter what, the main question that arises is what happens to the twist of the radio waves when their polarization changes (as happens when the radio waves are bounced back by the ionosphere). If somehow they maintain their twist, then you could do DX in that fashion without losing the advantage of that method. However, if they do lose the twist, then you are out of luck.

The other question that is of importance would be how that stuffing of the radio bands is achieved. Are the different "twists" simply stacked on top of each other (like the different audio sub-carriers you find on any satellite transmission, e. g. for TV), or does the overall bandwidth of each transmission decrease (i. e. the bandwidth is somehow "wrapped up" in a frequency window far too narrow for ordinary transmission modes, e. g. commercial-quality FM signals (44.1 kHz bandwidth with a 95 kHz frequency shift) squeezed into the 500 Hz bandwidth usually necessary for CW. ;)

But no matter what, this is far too interesting to ignore and definitely worth some experimentation.
Irayo for this topic. :)

EDIT:
Before I forget: Narrowing the bandwidth of a transmission has two other very important advantages: The less bandwidth is used, the stronger the signal gets on the transmitting end, and the less noise gets through to the receiver. That means that the signals have a much better capability of blasting through any QRM and QRN present and at the same time reduces the impact of these conditions on the receiver (less bandwidth means less noise that is picked up along with the signals).
Example: An SSB signal with 2.3 kHz of bandwidth must have a strength of 10 dB above background noise to be understood. A CW signal with only 500 Hz of bandwidth only has to be 6 dB above noise level and can still be recognized.


"Sawtute ke tsun nivume - fo ke kerame!"
-- Neytiri te Tskaha Mo'at'ite

"There are two things that are infinite: Human stupidity and the universe. However, I'm not yet sure about the universe."
-- Albert Einstein

"He who gives up freedom for security deserves neither and loses both."
-- Benjamin Franklin

Seze Mune

Wow, this is really interesting to me, although I won't pretend to understand it completely.

I come at ionization from a different realm, that of the effect on living tissue.  It appears that negative ionization has health benefits and positive has the opposite effect.  I am not familiar with the biology behind this, but more with the end result.

Your information, though, has me wondering about the effect of lightning strikes on atmospheric conditions for radio transmissions. 

There are stimulatory effects on plant and microbial life as the electrical activity disseminates through the ground after a strike.  I presume there is more electrical activity in storms during the spring which helps to jump start Eywa's connectivity and flow through our collective symbiotic cycles.  This reminds me of the scene in Avatar where Grace and Norm are taking readings from the tree's roots, just before Jake does his dance with the titanothere.   :D

Ningey

#7
Quote from: Seze Mune on October 15, 2011, 09:42:31 AM
Wow, this is really interesting to me, although I won't pretend to understand it completely.

I come at ionization from a different realm, that of the effect on living tissue.  It appears that negative ionization has health benefits and positive has the opposite effect.  I am not familiar with the biology behind this, but more with the end result.

Your information, though, has me wondering about the effect of lightning strikes on atmospheric conditions for radio transmissions. 

There are stimulatory effects on plant and microbial life as the electrical activity disseminates through the ground after a strike.  I presume there is more electrical activity in storms during the spring which helps to jump start Eywa's connectivity and flow through our collective symbiotic cycles.  This reminds me of the scene in Avatar where Grace and Norm are taking readings from the tree's roots, just before Jake does his dance with the titanothere.   :D

Well, ionization in living tissues and in the atmosphere are two entirely different stories.
The first one is based on the flow of ions in some liquid (sodium, potassium, chlorine, iodine, etc. ions being present in H2O) as well as the action of certain molecules that act as ion pumps, etc.
However, the ionization of the atmosphere is triggered by particles from the solar wind and cosmic radiation (especially the latter bumps electrons out of the molecules making up the upper layers of the atmosphere) so that ions can actually form (however, they tend to quickly reassociate and become neutral again if it weren't for the persistent cosmic radiation) - the same effect that causes oxygen in the upper stratosphere to split up when exposed to UV light and form ozone.

And in contrast to the effects on life thunderstorms and the likes have adverse effects on radio wave propagation and cause a dramatic increase in QRN. Amplitude-modulated waves (like true AM and also SSB) are distorted due to amplitude changes, and overall background noise increases. Only FM is quite well-protected from such effects, because it is a shift in frequency that causes the modulation, not the amplitude.
Other adverse conditions are an increase in magnetic activity of 'Rrta (the stronger it gets and/or the more it gets disturbed, the worse conditions become, even up to the point that the bands are closed despite all other factors indicating the contrary) or any solar flares which tend to disrupt DX transmissions as well.

Another interesting thing are aurorae. You can use them for DX transmissions on 2 m and below, with the aurorae acting in about the same manner as a Sporadic-E. The drawback with aurorae is that any phone (SSB and the likes) communication gets distorted and becomes unintelligible. Only CW is somewhat unaffected since you don't have any modulation here but simply switch an unmodulated carrier on and off here.

~~~

And as far as the thing with Jake and the angtsìk is concerned - didn't they react in the moment as Jake was playing with the loreyu, with the angtsìk reacting once the loreyu retreated into the ground...?
I guess it hasn't been for Norm and Grace measuring electrical activity in some tree roots, but rather Jake's meddling with the plant life that caught the animals' attention.


"Sawtute ke tsun nivume - fo ke kerame!"
-- Neytiri te Tskaha Mo'at'ite

"There are two things that are infinite: Human stupidity and the universe. However, I'm not yet sure about the universe."
-- Albert Einstein

"He who gives up freedom for security deserves neither and loses both."
-- Benjamin Franklin

Seze Mune

#8
Quote from: Ningey on October 15, 2011, 10:21:33 AM


Well, ionization in living tissues and in the atmosphere are two entirely different stories.
The first one is based on the flow of ions in some liquid (sodium, potassium, chlorine, iodine, etc. ions being present in H2O) as well as the action of certain molecules that act as ion pumps, etc.


Exactly.  This would be a great explanation for the science behind the scene with Grace and Norm.  One question never addressed is whether Eywa has a presence in what is generally considered to be non-living - like rocks - but that should probably be addressed within a more spiritual paradigm.

Quote from: Ningey on October 15, 2011, 10:21:33 AM
However, the ionization of the atmosphere is triggered by particles from the solar wind and cosmic radiation (especially the latter bumps electrons out of the molecules making up the upper layers of the atmosphere) so that ions can actually form (however, they tend to quickly reassociate and become neutral again if it weren't for the persistent cosmic radiation) - the same effect that causes oxygen in the upper stratosphere to split up when exposed to UV light and form ozone.

Hmm.  So the holes in the ozone layer are due to decreased ionization of oxygen in the upper stratosphere?  And decreased ionization could be due to...decreased cosmic radiation? No, that's not right, because there is increased cosmic radiation getting to the surface when the ozone layer isn't sufficient.  So that must mean there is less oxygen getting to that layer of the atmosphere....because there is now a greater concentration of carbon dioxide relative to the previous amount of oxygen?  Nvm, we are getting pretty far afield here...

Quote from: Ningey on October 15, 2011, 10:21:33 AM
And in contrast to the effects on life thunderstorms and the likes have adverse effects on radio wave propagation and cause a dramatic increase in QRN. Amplitude-modulated waves (like true AM and also SSB) are distorted due to amplitude changes, and overall background noise increases. Only FM is quite well-protected from such effects, because it is a shift in frequency that causes the modulation, not the amplitude.

Other adverse conditions are an increase in magnetic activity of 'Rrta (the stronger it gets and/or the more it gets disturbed, the worse conditions become, even up to the point that the bands are closed despite all other factors indicating the contrary) or any solar flares which tend to disrupt DX transmissions as well.

Which makes me want to look at a global gravitational map. It's intuitive that there is a correlation between electromagnetic activity and gravitational fields, and it looks like some scientific evidence has been turned up here:   http://arxiv.org/html/physics/9908024  I wonder what a study of radio waves in these odd gravitational fields would show.

Quote from: Ningey on October 15, 2011, 10:21:33 AM
Another interesting thing are aurorae. You can use them for DX transmissions on 2 m and below, with the aurorae acting in about the same manner as a Sporadic-E. The drawback with aurorae is that any phone (SSB and the likes) communication gets distorted and becomes unintelligible. Only CW is somewhat unaffected since you don't have any modulation here but simply switch an unmodulated carrier on and off here.

~~~

And as far as the thing with Jake and the angtsìk is concerned - didn't they react in the moment as Jake was playing with the loreyu, with the angtsìk reacting once the loreyu retreated into the ground...?
I guess it hasn't been for Norm and Grace measuring electrical activity in some tree roots, but rather Jake's meddling with the plant life that caught the animals' attention.


Yes, I mentioned Jake merely because that located the Grace-Norm scene within the film. I think more people would remember Jake's encounter with the angtsìk than Grace berating Norm for getting saliva in the sample. :D It was the scene with Grace and Norm which seemed to apply more to the discussion, at least in my mind.

Ningey

#9
Quote from: Seze Mune on October 15, 2011, 11:38:10 AM
Quote from: Ningey on October 15, 2011, 10:21:33 AM
Well, ionization in living tissues and in the atmosphere are two entirely different stories.
The first one is based on the flow of ions in some liquid (sodium, potassium, chlorine, iodine, etc. ions being present in H2O) as well as the action of certain molecules that act as ion pumps, etc.

Exactly.  This would be a great explanation for the science behind the scene with Grace and Norm.  One question never addressed is whether Eywa has a presence in what is generally considered to be non-living - like rocks - but that should probably be addressed within a more spiritual paradigm.

I would have to mode-switch for that vantage point. However, as it seems, the unobtainium seems to have a great influence on Eywa's presence on Pandora. I suspect that where large deposits of unobtainium can be found, Eywa's presence is strongest. Just keep in mind the vicinity of the Tree of Souls - the rock structures there speak volumes.
Yet the question to be answered here is in how far the plant and animal life on Pandora can interact with that material, but I reckon that this is somehow part of the neural network that makes up Eywa.
The most interesting thing is that almost all such sites are somehow sacred for the Na'vi, and spoiling with them is going to provoke their ire (as can be seen in the scene with the ayUtral ayMokriyä). It could be worth splitting this topic off this thread since the connection to the initial topic seems to be lost in this part of the discussion...

Quote from: Seze Mune on October 15, 2011, 11:38:10 AM
Quote from: Ningey on October 15, 2011, 10:21:33 AM
However, the ionization of the atmosphere is triggered by particles from the solar wind and cosmic radiation (especially the latter bumps electrons out of the molecules making up the upper layers of the atmosphere) so that ions can actually form (however, they tend to quickly reassociate and become neutral again if it weren't for the persistent cosmic radiation) - the same effect that causes oxygen in the upper stratosphere to split up when exposed to UV light and form ozone.

Hmm.  So the holes in the ozone layer are due to decreased ionization of oxygen in the upper stratosphere?  And decreased ionization could be due to...decreased cosmic radiation? No, that's not right, because there is increased cosmic radiation getting to the surface when the ozone layer isn't sufficient.  So that must mean there is less oxygen getting to that layer of the atmosphere....because there is now a greater concentration of carbon dioxide relative to the previous amount of oxygen?  Nvm, we are getting pretty far afield here...

Kehe. The mechanisms here are different. It is true that UV rays can split oxygen molecules apart, but no ionization takes place here (since UV rays are non-ionizing), however, they manage to break the bond between two oxygen atoms.
Most of them reassociate with other free oxygen atoms almost immediately, but some manage to attach themselves to another oxygen molecule, thereby forming O3, an unstable molecule that eventually splits off the "superfluous" atom - but ozone nevertheless absorbs UV rays.
What actually thins out the ozone layer is not due to cosmic radiation or the likes, but a reaction of ozone with nitrogen oxides of any sort - with the effect that when more UV radiation comes through to the surface, you are going to see the exact opposite reaction: Nitrogen oxides are split apart by the UV rays which causes free nitrogen molecules and oxygen atoms to form - which then attach themselves to the oxygen molecules near the surface. That's where those ozone warnings the authorities sometimes issue come from.

Quote from: Seze Mune on October 15, 2011, 11:38:10 AM
Quote from: Ningey on October 15, 2011, 10:21:33 AM
And in contrast to the effects on life thunderstorms and the likes have adverse effects on radio wave propagation and cause a dramatic increase in QRN. Amplitude-modulated waves (like true AM and also SSB) are distorted due to amplitude changes, and overall background noise increases. Only FM is quite well-protected from such effects, because it is a shift in frequency that causes the modulation, not the amplitude.

Other adverse conditions are an increase in magnetic activity of 'Rrta (the stronger it gets and/or the more it gets disturbed, the worse conditions become, even up to the point that the bands are closed despite all other factors indicating the contrary) or any solar flares which tend to disrupt DX transmissions as well.

Which makes me want to look at a global gravitational map. It's intuitive that there is a correlation between electromagnetic activity and gravitational fields, and it looks like some scientific evidence has been turned up here:  http://arxiv.org/html/physics/9908024  I wonder what a study of radio waves in these odd gravitational fields would show.

That would be worth pursuing, though, since one can assume that the four basic forces of the universe are somehow correlated. The relationship between the Electromagnetic and the Weak forces has already been found (the so-called Weak-Electric force), but that still has to be figured out how the gravitation and the Strong force come into play in that equation.
The main effect of strong gravitational fields, though, is that the surrounding space is bent - the stronger the field, the greater the distortion - and should the cause of that gravitational field be rotating itself you are going to notice other interesting effects (like the space in the vicinity rotating as well), which in turn would be in for some relativistic effects (and therefore most likely affect those twisted radio waves, too).

Quote from: Seze Mune on October 15, 2011, 11:38:10 AM
Quote from: Ningey on October 15, 2011, 10:21:33 AM
Another interesting thing are aurorae. You can use them for DX transmissions on 2 m and below, with the aurorae acting in about the same manner as a Sporadic-E. The drawback with aurorae is that any phone (SSB and the likes) communication gets distorted and becomes unintelligible. Only CW is somewhat unaffected since you don't have any modulation here but simply switch an unmodulated carrier on and off here.

~~~

And as far as the thing with Jake and the angtsìk is concerned - didn't they react in the moment as Jake was playing with the loreyu, with the angtsìk reacting once the loreyu retreated into the ground...?
I guess it hasn't been for Norm and Grace measuring electrical activity in some tree roots, but rather Jake's meddling with the plant life that caught the animals' attention.


Yes, I mentioned Jake merely because that located the Grace-Norm scene within the film. I think more people would remember Jake's encounter with the angtsìk than Grace berating Norm for getting saliva in the sample. :D It was the scene with Grace and Norm which seemed to apply more to the discussion, at least in my mind.

Sorry, somehow that fell short of me. :-\
But yes, from that vantage point one could assume that such conditions could give Eywa a boost (like the plasma storms you can see in one of the missing scenes of the Collector's Edition - they dramatically increase the level of electric activity, thereby most likely making any radio transmissions moot and causing a surge in the neural network). Looks like James Cameron has done a great job in placing Pandora where he did - there's also physics behind this phenomenon, and this should also be worth splitting off from this thread to pursue that matter further.


"Sawtute ke tsun nivume - fo ke kerame!"
-- Neytiri te Tskaha Mo'at'ite

"There are two things that are infinite: Human stupidity and the universe. However, I'm not yet sure about the universe."
-- Albert Einstein

"He who gives up freedom for security deserves neither and loses both."
-- Benjamin Franklin