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Europe Is Testing 12.5 Gbps Wireless
Lorien_the_first_one brings word that in Europe, a breakthrough for post-4G communications has been announced. A public-private consortium known as IPHOBAC has been developing new communications technology that is near commercialization now. Quoting: "With much of the mobile world yet to migrate to 3G mobile communications, let alone 4G, European researchers are already working on a new technology able to deliver data wirelessly up to 12.5Gb/s. The technology — known as 'millimeter-wave' or microwave photonics — has commercial applications not just in telecommunications (access and in-house networks) but also in instrumentation, radar, security, radio astronomy and other fields."
Im already using it. Its awesome.
When we look at how far behind the American wireless industry is compared to the overseas systems, it's not always correct to simply look at the current status. It's much more important to look at the growth over time, because it is only when you do that do you realize that the American system is keeping pace with European and Asian cellular systems.
Yes, at any particular moment in time the American system may seem far behind, but at some point we do upgrade to the latest and greatest. It just takes a lot more time to decide which version of the latest and greatest we will implement.
So it's much more like taking an elevator to go from one floor to another here in the US. We don't bother with every individual step in between and we get to the same place as the stair-climbers eventually too.
Most of us bathe in kilowatts of infra red radiation at shorter wavelengths (and higher photon energy) than microwaves. I don't see how photons of lower energy could be causing us problems.
http://michaelsmith.id.au
You're talking crap.
Whilst IR photons have a higher energy than microwaves, so do visible light photons.
On the other hand, opacity and absorbtion of various human tissues, is a complex relationship with wavelength.
4G is a mobile solution where the signal is radiated every direction and cells get blanketed by signals that are useful to mobile devices. Millimeter wave is a point-to-point technology that requires a clear line of sight and should be compared to free space optic laser solutions. You so much as block the beam with a tree branch and it doesn't work. Can we try to get some quality reporting on slashdot? We have plenty of experts in this community and headlines like these need to get slapped down. We don't need another clueless USA bashing headline.
welcome our new 12.5Gbps brain tumor inducing overlords
actually I am happy to see you, however that is in fact a banana in my pocket.
The article is comparing 4G performance at 150 Mbps using only 20 MHz of spectrum to to millimeter wave technology which uses tens of GHz for line-of-sight application for multi gigabit links. Then it suggest that the rest of the world is lagging because of this bogus comparison. OK, maybe it's not just US bashing, but it's bashing the rest of the world.
the correct link is http://www.ist-iphobac.org/, not http://www.iphobac-survey.org/
The comparison with 3G/4G systems is misleading, as these terms denote wide-area cellular telephone networks. Our cellular links are mobile, work over long ranges, and do not require a line-of-sight path from transmitter to receiver. 60 GHz wireless links, by comparison, typically require highly directive antennas, ie. the transmitter radiates energy directly at the receiver in a narrow beam. This makes it more suitable for fixed point link, rather than mobile, at this stage of development. Also, 60 GHz wireless signals are highly attenuated as they pass through solid objects, hence the need for a line-of-sight path. So, while its true mm-wave communications offers unparalleled wireless data rates, the comparison with cellular networks is not necessarily a good one.
Actually, resonant processes are the ones that depend absolutely upon the photon energy, and the energy of a microwave photon is too low to do anything interesting. Microwaves can do work by a nonresonant, thermal process, but that's it.
A resonant process is one in which the photon has the right energy to trigger a particular transition. Ionising radiation (UV, x-rays, etc.) works by a resonant process, and depends on the quantum of radiation having enough energy to eject an electron from the molecule. As you go down in energy from there, you have enough energy per photon to resonantly electronically excite molecules (visual light, used in the eyes to detect light) or vibrationally excite (IR), or down at the bottom, to rotationally (microwave), and then translationally excite molecules.
Correspondingly, it gets harder and harder to cause any chemistry with those photons. It's trivial to break up a molecule by shifting its electrons around or ejecting them altogether, or to a lesser extent it's possible to chop something up by exciting a particular molecular stretching vibration such that the bond(s) dissociate(s). However it's a serious challenge to cleave a bond with a rotational excitation alone.
So, how could a microwave do any chemistry, and thus damage, to your tissues? It's a simple thermal process. When you rotationally excite a molecule, in the gas phase, the molecule, or part of it, changes its rotational motion in some way. There are couplings between rotational and vibrational motions, and upwards to electronic excitations. In the solution or solid phase, there are also couplings to the translational motion of the molecules, meaning that ultimately the energy from the microwave can end up speeding up the molecule's motion, which is plain old heating.
So the energy you dump in with the microwaves becomes "thermalised", spreading over the whole range of states evenly, with a pretty huge chunk of it going into heating up the material. That heat lets you do old-fashioned collision-activated chemistry. What the anti-EM movement don't want you to think about is that this thermal process is entirely dependent on your exposure. It's like standing next to a furnace. A foot away, you're toast. Six feet away, you're warm. One hundred feet away, you don't know it exists.
In summary, it is not possible for radio to cause you thermal damage because the exposure is simply too low. No non-thermal, resonant process for damage has been shown to exist, and trivial physical chemistry makes it clear that one probably never will be found.
No kidding!!! What do you say at this point?
Your implicit assumption that higher energy photons are universally more dangerous than lower energy photons would seem to speak for the latter.
This has been experimentally verified in experiments on the photoelectric effect. Indeed, Einstein was awarded the Nobel Prize in physics in 1921 "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect" (emphasis mine; notice that Einstein did not win the prize "because of relativity", as many would assume). Below a certain energy level per photon, nothing happens no matter how intense the light. Above the threshold, something happens (with the rate dependent on the intensity of the light).
Of course, thermal warming can also happen. In recent years, microwave-assisted organic synthesis was a big fad. But the most careful studies have demonstrated that the so-called "microwave effect" is simple thermal heating in all known cases, and despite theoretical explanations for why a non-thermal microwave effect might exist (going so far as to predict the types of reactions for which the largest effect might be found) and papers claiming the discovery of such effects, effects seen to date are purely thermal. See this J Org Chem paper. Any effect we see from a cell phone in the pocket would appear to be the same effect as simply warming our thigh a miniscule bit.