Iwant to add some comments here regarding the white paper. When the paper gets to the core of the technology, it appears as though there's no cattle to go with the big hat.
You see, upon reading the paper, it becomes apparent that this technology purports to work by modulating data in whatever form -- analog, 64 QAM digital or whatever onto subcarriers at various microwave frequencies. The subcarriers and their modulating signals are chosen so that they occupy adjacent bands in the RF spectrum. For example, if channels are stacked together so that they fill up 20GHz of spectrum, then it ought to be possible to encode a total of 100-160GB of data if the individual channels are modulated with a 256 QAM technique. I want to point out that this type of channel stacking is purported, in the white paper, to be be done before any electro-optical modulation is performed on the output laser beam.
The paper also says that the above RF signal is applied to the electro-optical crystal which performs an amplitude modulation. There is a vague description of the modulator, at best. What is perfectly clear, however, is that information could be transmitted on a light beam at these data rates with QAM encoding and plain, old-fashioned AM modulation techniques applied to a very narrow linewidth laser beam.
There appears to be no use of or even the need to use multiple LaGuerre orders or any kind of stacking of photons in three-dimensional space. If photons were being stacked in independent Laguerre Orders, as the entrepreneuers claim, then there would need to be an independent electrical stimulus for each order. Where is the unique role that ORS will play? Hence, where are the cattle?
What I think that we have in SR is a group of good optical technicians pursuing what may be good optical technology with little effective patent protection. It may very well be that nobody in the world, for very practical reasons, can accomplish what SR claims to be accomplishing. It also may very well be that Lucent Technologies is about to come out with something similar in the very near future.
If there was good patent protection, then I think that SR could release a white paper which cuts much of the elegant physics and describes the technology in clear, crisp detail.
I want to reiterate that this is just my opinion. |
