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Comment Re:Will it be practical? (Score 1) 142

You keep repeating this, but... your IEEE paper does not "discredit" OAM or show that it's a "scam." Orbital Angular Momentum is a legitimate physical property of systems, both material (i.e. spinning tops, atoms, subatomic particles) and electromagnetic (light and radio waves). The IEEE paper is showing that doing so simply offers no major advantage over standard MIMO schemes. In fact, from the abstract of your paper:

We demonstrate that, for certain array configurations in free space, traditional MIMO theory leads to eigen-modes identical to the OAM states. From this we conclude that communicating over the sub-channels given by OAM states is a subset of the solutions offered by MIMO, and therefore does not offer any additional gains in capacity.

In other words, OAM is a perfectly legitimate technique for encoding data. It just happens to be a subset of what's already capable with MIMO. It's also worth noting that your paper discusses radio waves, and the OAM demonstration discussed in the submission is in the optical. There may be limitations that prevent certain MIMO techniques from being applicable to optical transmission, especially in guided-wave situations (i.e. optical fiber). In fact, the research group I worked with during my Ph.D. was looking at encoding extra information on single photons using OAM to increase the data capacity of quantum communication networks, a situation where MIMO is almost certainly not applicable.

It's worth noting that Alan Willner is no nutjob. He's worked at Bell Labs, has a chaired professorship at USC, is a fellow of IEEE, OSA and SPIE, and is an editor-in-chief for several reputable academic journals (JLT, Optics Letters, JSTQE). I had the pleasure of working with him on an unrelated project 5 or 6 years ago, and there's no reason to believe that he's trying to pull the wool over anybody's eyes. There's certainly no professional reason for him to do so, his CV speaks for itself: http://csi.usc.edu/faculty/willner.html

Comment Re:If they can do this from earth... (Score 2, Informative) 165

I think your suspicions are probably correct.

Lucky Imaging relies on the fact that every so often, a really high-quality image makes it through the atmosphere almost unperturbed (based on the Kolmogorov model of turbulence). While I don't know whether the same model can be applied to cosmic gas clouds, there may be another model that could accurately model the phase distortions those clouds impress upon a wavefront.

To achieve this one must take many very short-exposure (compared to the time-scale of atmospheric turbulence, or gas-cloud turbulence in the case we're considering) images of the source. However, distant (or dim) objects often require reasonably long exposure times in order to collect a large enough amount of light to be able to see the image. The problem with this technique may simply be that the exposure time necessary for the Lucky Image algorithm to work is too short to actually collect enough light to create a good image in the first place.

Submission + - I'm not a spammer

tfinniga writes: A spammer has recently started using my domain name as "From:" addresses when sending out spam. I'm worried about my domain being blacklisted, and I'm annoyed by the bounces — I'm getting about 1000 bounce messages a day. Unfortunately, I give out a different email address to each site I visit: slashdot@example.com, paypal@example.com, amazon@example.com, etc., and the spammer is using a different address for each mail, so simple address filtering doesn't work.

What is the best way of avoiding being put on a blacklist, and dealing with the flood of bounces?
Data Storage

Submission + - Samsung Begins Shipping Hybrid Hard Drives

writertype writes: "Samsung has become the first company begin shipping hybrid hard drives, we report on ExtremeTech. Unfortunately, there's no word yet (besides "soon") on when retail shipments will begin, or when (or if) 3.5-inch models will be available. Note that these are different than the ReadyBoost USB flash drives optimized for Vista; hybrid drives contain a smaller amount of flash, and work as a write cache for your notebook drive, extending battery life."
Privacy

Submission + - Canada Rejects Anti-Terror Laws

Coryoth writes: "The Canadian parliament has voted against renewing anti-terror laws that had been introduced after September 11, 2001. The rejected laws included provisins to hold terror suspects indefinitely, and to compel witnesses to testify, and were in some sense Canada's version fo the PATRIOT Act. The laws were voted down in the face of claims from the minority Conservative government that the Liberal Party was soft on terror, and despite the fact that Canada has faced active terrorist cells in their own country. The anti-terror laws have never been used, and it was viewed that they are neither relevant, nor needed, in dealing with terrorist plots. Hopefully more countries will come to the same conclusion."
Movies

Submission + - BitTorrent video download store falls flat

seriouslywtf writes: We've all heard about BitTorrent going legit this week with legal movie and TV show downloads. Ars Technica took a look at the service to see how useable it was and ran into a few snags, including not being able to download or even open the video files on some computers. However, the ones that they did manage to open varied a lot in quality. Overall, they blame DRM. From the article:

Without knowing whether browser compatibility and dysfunctional video files are a rare occurrence or not, it's hard to say whether BitTorrent's service is a good one overall. Our initial experiences have been disappointing and frustrating, and guess what the culprit is once again? DRM. Why the DRM failed to work on 50% of our purchases is not clear, but whatever the cause, it's simply unacceptable.
Patents

Submission + - MP3's Loss, Open Source's Gain

nadamsieee writes: "Eliot Van Buskirk has an interesting piece over at Wired about the fall-out from Microsoft's recent courtroom loss to Alcatel-Lucent over MP3 patents. From the article: "Alcatel-Lucent isn't the only winner in a federal jury's $1.52 billion patent infringement award against Microsoft this week. Other beneficiaries are the many rivals to the MP3 audio-compression format... Now, with a cloud over the de facto industry standard, companies that rely on MP3 may finally have sufficient motivation to move on. And that raises some tantalizing possibilities, including a real long shot: Open-source, royalty-free formats win.""
Hardware

Pentium 4 631 Overclocked to 8 GHz 271

Andreas writes "There are always those who are willing to take things one step further than others. A group of guys known as OC Team Italy is one of them. They recently pushed an Intel Pentium 4 631 to over 8000MHz using an ASUS P5B with modified voltage regulation and liquid nitrogen. Overclocking is cool and all, but this extends beyond what some would perhaps call useful. Still a milestone though."

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