But you are disregarding multipath: the energy will be reflected and refracted at these frequencies, and thus the analogy with vision falls apart. In outer space you are correct (when using very large arrays), but in an indoor environment there are lots of reflections, and thus the different links will interfere with each other.
RF reception and transmissio is very important for cellphones. And tuned circuits can be eliminated completely, but this puts ridiculous demands on the AD/DA-converters for most real world applications. The DA-converter could leave enough power to drive the antenna, and impedance matching could be broadband, and thus not tuned.
A more practical application is to have a wideband frontend, and then sample a complete band, such as the 2.45 GHz ISM-band, and leave all the channel filters for different aplications (BT, WiFi, etc.) and demodulation to software. This will not be the most energy efficient implementation, but more flexible than dedicated tranciever chipsets.
But isn't a digital packet based radio standard exactly what the winner of this auction has the possibility to implement? And it is done in digital satellite radio (to some extent). So we are getting there, but to radically alter eveerything tomorrow, and exchange almost every radio transmitter and reciever in use at one time, would be extremely expensive, unpopular and really not a good way to handle things, IMHO.
As long as one of these broadcaster doesn't start to send HDTV instead of radio, which will use all of the available bandwidth, sending packets all the time. You are still vulnerable to exactly the same things as in all other packet data networks.
TCP/IP works fine on a much more refined transmission medium: no interferes, no fading, available bandwidth DC-daylight (OK, not all the way to daylight, but it is only limited by the acceptable losses in the link), etc. To make something work in such a medium is much much simpler than in the messy world of real world radio wave propagation!
Openspectrum still needs somebody to set the rules (protocols, power levels, certifications etc.). And there are numerous problems that are not solved yet by the people advocating this idea, the most important ones being detection of very low power transmitters, such as GPS and mars satellites, and the hidden node problem. (A is transmitting to B which is reciving. Now add transmitter C, which is much closer to B than A, and thus will drown out the transmission from A if it start transmitting also. The problem is when there is a wall blockan A from C, making it impossible for C to detect A, but at the same time there still is a clear line of sight between B and C...)
Pectrum scarcity is only a fallacy if you are prepared to exchange every radio transmitter and reciver with one top-of-the line model, which will be much more expensive, considerably larger and have a very high power consumption, compared to a typical FM-radio or cellphone. And then you will still have to solve the hidden-node problem , which seems to be a very hard one....
Spectrum scarcity is very much a reality yesterday, today and will still be tomorrow, if you look at a realistic scenarios.
Lai and Singh's work have not been supressed: rather it has shown to be hard to replicate.
And there is another explanation to the statements in the article: they mechanism of work is not as the inventors think (not at all unusual) and it is only the heat that gives the result. The article is far too thin in details to know for sure.
Why 1200 different frequencies? And what mechanism is used to break the bonds whith microwaves? -the photon energy at these frequencies is to low to be ionizing. I will stay sceptical until further details emerge...
True. For ordinary computer control there is not that much to gain for most patients, especially as a computer mouse essentially is a 2 DOF device, plus the click. But if we look at harder things, such as controlling limbs with multiple degrees of freedom (an arm, without the fingers and palm, has 7 to start with) at the same time, or restoring hearing and vision, we need to interact directly with the nervous system. Which is exactly what is done today, when we restore hearing with cochlear implants. These have electrodes that directly stimulates the auditory nerve. The simple experiments you see today is due to the technology being in its infancy, they are not the target application.
If you are serious in comparing the directivity from a laser to the one from a pringles can, I recommend you to read up on some basic antenna technology. A pringles can is still radiating in all directions, but has an increased gain in its main lobe. But it is nowhere as directional as a laser. Not even close.
Nobody has ever said that RF-signals interfere with each other in the air. They interfere with each other in the reciver. And your reciever will get signals from multiple transmitters, as antennas are in no way as directive, i.e. has as narrow beams, as lasers. The opposite is (almost) true: most small and handheld devices do recieve signals from all directions, including up and down. Thus they will recive interfering signals. And thus it is easy to shut down a CDMA-network: you only need a handful of correctly programmed transmitters to shut down a city. That is way we need regulations. (Radio/antenna guys: Yes, this is a simplification, but true for the practical case under discussion.)
And this is the problem of all "stereo"-picture technologies today, with the exception of holograms: they only take one of many depth cues that the brain use into account. The movement of the head is important, and it is not only large movements, but also small, almost imperceptible rotations of the head that are important. (You can test this yourself: close one eye and note how what you see changes if you rotate your head as little as possible.) Another depth cue that is not covered is the focus of the eye: you will always have a contradiction in you head (which may give you a headace) as your eye has to be focused on the screen, but the depth information from the difference in the viewed images on the right and left eye tells you otherwise. As long as these other cues are not alse given, you will have the "cut out pictures stacked behind each other" persception of 3D in the cinema.
Most definitly. No color reproduction technology in existence has the capability of reproducing all the colours that the human can experience. (i.e. the Gamut, nice reading in Wikipedia: http://en.wikipedia.org/wiki/Gamut )
Include with that the ability to exchange ringtones, photos, and all other info stored on the phone through bluetooth, wifi, or a working USB connector, bypassing the carrier and their outrageous charges altogether, and interesting times are ahead.
This is possible with standard GSM-phones today. I am fairly certain about this, I did it the other night at the pub, using BT...
(I also have call duration and traffic counter in the phone. And this is in Europe, BTW,)
The problem is that if the invading country is big enough, and has enough military and economic power, you are still toast, regardless of what international rights do say. (Example: Tibet). As Zeeland has very few friends, and is not even a member of the UN, an "invasion" from GB will probably go unnoticed. But obviously this does not carry over to Canada: GB will probably have some issues with it getting invaded... And Canada has more friends in the UN.
I think that I am somewhat knowledgeable on the subject. Please tell me how it is more power efficient to do a radio reciver in software than in hardware? I can not see how to do it.
Which was the test phase of the project, according to the same article. I speak of commercial deployment. Completly different things. (The development of the NMT system started in 1971.)
The numbers form the study (males and females) of cell phone users between 15-21 years: 10,968 and between 10-15 years: 45,680. Total number of subjects were 420,095 persons. The study was supported by the Danish Strategic Research Council and the Danish Cancer Society. According to the article: "The funding sources were not involved in the study design or data collection, analyses, or interpretation." The article do discuss the strengths and weaknesses of the study, any blame on putting things in a better light should be placed on the regular media that is reporting about their article and findings.
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But you are disregarding multipath: the energy will be reflected and refracted at these frequencies, and thus the analogy with vision falls apart. In outer space you are correct (when using very large arrays), but in an indoor environment there are lots of reflections, and thus the different links will interfere with each other.
RF reception and transmissio is very important for cellphones. And tuned circuits can be eliminated completely, but this puts ridiculous demands on the AD/DA-converters for most real world applications. The DA-converter could leave enough power to drive the antenna, and impedance matching could be broadband, and thus not tuned. A more practical application is to have a wideband frontend, and then sample a complete band, such as the 2.45 GHz ISM-band, and leave all the channel filters for different aplications (BT, WiFi, etc.) and demodulation to software. This will not be the most energy efficient implementation, but more flexible than dedicated tranciever chipsets.
But isn't a digital packet based radio standard exactly what the winner of this auction has the possibility to implement? And it is done in digital satellite radio (to some extent). So we are getting there, but to radically alter eveerything tomorrow, and exchange almost every radio transmitter and reciever in use at one time, would be extremely expensive, unpopular and really not a good way to handle things, IMHO.
As long as one of these broadcaster doesn't start to send HDTV instead of radio, which will use all of the available bandwidth, sending packets all the time. You are still vulnerable to exactly the same things as in all other packet data networks.
TCP/IP works fine on a much more refined transmission medium: no interferes, no fading, available bandwidth DC-daylight (OK, not all the way to daylight, but it is only limited by the acceptable losses in the link), etc. To make something work in such a medium is much much simpler than in the messy world of real world radio wave propagation!
Openspectrum still needs somebody to set the rules (protocols, power levels, certifications etc.). And there are numerous problems that are not solved yet by the people advocating this idea, the most important ones being detection of very low power transmitters, such as GPS and mars satellites, and the hidden node problem. (A is transmitting to B which is reciving. Now add transmitter C, which is much closer to B than A, and thus will drown out the transmission from A if it start transmitting also. The problem is when there is a wall blockan A from C, making it impossible for C to detect A, but at the same time there still is a clear line of sight between B and C...)
Pectrum scarcity is only a fallacy if you are prepared to exchange every radio transmitter and reciver with one top-of-the line model, which will be much more expensive, considerably larger and have a very high power consumption, compared to a typical FM-radio or cellphone. And then you will still have to solve the hidden-node problem , which seems to be a very hard one.... Spectrum scarcity is very much a reality yesterday, today and will still be tomorrow, if you look at a realistic scenarios.
I was commenteing on their work in the microwave range, not on ELF-EMF. And the supression is in the eye of the beholder.
There has not to be any reason for their use of multiple frequencies, more than that the inventors believe that it is important.
Lai and Singh's work have not been supressed: rather it has shown to be hard to replicate. And there is another explanation to the statements in the article: they mechanism of work is not as the inventors think (not at all unusual) and it is only the heat that gives the result. The article is far too thin in details to know for sure.
Because 2.45 GHz is not the resonant frequency of water, it is a myth. The water gets hot by absorbing energy, plain and simple.
Why 1200 different frequencies? And what mechanism is used to break the bonds whith microwaves? -the photon energy at these frequencies is to low to be ionizing. I will stay sceptical until further details emerge...
True. For ordinary computer control there is not that much to gain for most patients, especially as a computer mouse essentially is a 2 DOF device, plus the click. But if we look at harder things, such as controlling limbs with multiple degrees of freedom (an arm, without the fingers and palm, has 7 to start with) at the same time, or restoring hearing and vision, we need to interact directly with the nervous system. Which is exactly what is done today, when we restore hearing with cochlear implants. These have electrodes that directly stimulates the auditory nerve. The simple experiments you see today is due to the technology being in its infancy, they are not the target application.
If you are serious in comparing the directivity from a laser to the one from a pringles can, I recommend you to read up on some basic antenna technology. A pringles can is still radiating in all directions, but has an increased gain in its main lobe. But it is nowhere as directional as a laser. Not even close.
One thing to remember when comparing plans in US and in Europe is that in Europe there is no charge for incoming calls, or for incoming SMS.
Nobody has ever said that RF-signals interfere with each other in the air. They interfere with each other in the reciver. And your reciever will get signals from multiple transmitters, as antennas are in no way as directive, i.e. has as narrow beams, as lasers. The opposite is (almost) true: most small and handheld devices do recieve signals from all directions, including up and down. Thus they will recive interfering signals. And thus it is easy to shut down a CDMA-network: you only need a handful of correctly programmed transmitters to shut down a city. That is way we need regulations. (Radio/antenna guys: Yes, this is a simplification, but true for the practical case under discussion.)
Except that such directivity requires ridiculous large antennas at RF-frequencies...
And this is the problem of all "stereo"-picture technologies today, with the exception of holograms: they only take one of many depth cues that the brain use into account. The movement of the head is important, and it is not only large movements, but also small, almost imperceptible rotations of the head that are important. (You can test this yourself: close one eye and note how what you see changes if you rotate your head as little as possible.) Another depth cue that is not covered is the focus of the eye: you will always have a contradiction in you head (which may give you a headace) as your eye has to be focused on the screen, but the depth information from the difference in the viewed images on the right and left eye tells you otherwise. As long as these other cues are not alse given, you will have the "cut out pictures stacked behind each other" persception of 3D in the cinema.
That only leaves the reproduction part: not (AFAIK) possible in print, in theory possible with luminous displays, but extremely expensive...
Most definitly. No color reproduction technology in existence has the capability of reproducing all the colours that the human can experience. (i.e. the Gamut, nice reading in Wikipedia: http://en.wikipedia.org/wiki/Gamut )
Here is a link to an aerial photograph of the launch site, which is not inside the city of Kiruna, but close by. http://tinyurl.com/2d6qna
Include with that the ability to exchange ringtones, photos, and all other info stored on the phone through bluetooth, wifi, or a working USB connector, bypassing the carrier and their outrageous charges altogether, and interesting times are ahead.
This is possible with standard GSM-phones today. I am fairly certain about this, I did it the other night at the pub, using BT...
(I also have call duration and traffic counter in the phone. And this is in Europe, BTW,)
The problem is that if the invading country is big enough, and has enough military and economic power, you are still toast, regardless of what international rights do say. (Example: Tibet). As Zeeland has very few friends, and is not even a member of the UN, an "invasion" from GB will probably go unnoticed. But obviously this does not carry over to Canada: GB will probably have some issues with it getting invaded... And Canada has more friends in the UN.
I think that I am somewhat knowledgeable on the subject. Please tell me how it is more power efficient to do a radio reciver in software than in hardware? I can not see how to do it.
Which was the test phase of the project, according to the same article. I speak of commercial deployment. Completly different things. (The development of the NMT system started in 1971.)
The numbers form the study (males and females) of cell phone users between 15-21 years: 10,968 and between 10-15 years: 45,680. Total number of subjects were 420,095 persons. The study was supported by the Danish Strategic Research Council and the Danish Cancer Society. According to the article: "The funding sources were not involved in the study design or data collection, analyses, or interpretation."
The article do discuss the strengths and weaknesses of the study, any blame on putting things in a better light should be placed on the regular media that is reporting about their article and findings.