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1.  

   Interference is electronics, not physics

   

   Anonymous Coward, Aug 13th, 2004 @ 5:44pm

   
   

   Electromagnetic waves do not interfere with one other. So-called "interference" is really an artifact of engineering design decisions made early in the twentieth century, and perpetuated to this day. Channels can be made arbitrarily narrow, limited only by the cost of the electronics we choose to use. If we'd be willing to increase the cost of any radio-frequency device we use by just a few bucks -- and if the FCC would join the 21st century -- we'd have arbitrarily as much spectrum as we choose to have. We need to stop perpetuating the myth that spectrum is fundamentally limited. That's like saying there are only so many colors in the rainbow.

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2.  

   Re: Interference is electronics, not physics

   

   Mike (profile), Aug 13th, 2004 @ 5:59pm

   
   

   Indeed. You are absolutely right... it is an electronics, not a physics problem. But, let's face reality, the electronics DO CAUSE INTERFERENCE right now. Simply opening up the spectrum doesn't change that. Fixing the electronics would. So, let's fix the electronics and THEN talk about opening the spectrum.

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3.  

   Re: Interference is electronics, not physics

   

   DV Henkel-Wallace, Aug 13th, 2004 @ 9:09pm

   
   

   I doubt Shannon would have agreed with you, as you have stated it.

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4.  

   Beyond the physics

   

   dorpus, Aug 13th, 2004 @ 10:55pm

   
   

   Doesn't this tie into Western notions of respecting personal boundaries/space? Westerners, Americans in particular, take offense when people stand too close to them, or crash into them without saying anything, or reach around them to get a spoon without saying anything. The cell phone culture challenges the culture of personal boundaries, though so far people have not put up great resistance yet. In a "globalized" world, will the airwaves start to look more like a street scene in Calcutta, where a mother in a crowded bus might place a baby on a stranger's lap without asking, or people go to the bathroom in the middle of the street?
   

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5.  

   Re: Interference is electronics, not physics

   

   Peter F Bradshaw, Aug 14th, 2004 @ 7:36am

   
   

   Your comment regarding Shannon is right on the money.
   Further there are serious physics / mathemetics problems to consider. First is that all electronics that amplifies is non linear. Hence the interference (IM). Second is that signal processing is necessarilly constraned by being done in minimum phase. Third the Economist article ignores the fact that there is a minimum code seperation in any CDM over FDM schema (as there are minimum frequency distances in a pure FDM schema). Likewise there are minimum distances between slots in a TDM scheme.
   I love the directional antenna idea. To get a certain directivity a certain aperture (in wavelengths) is required. For most reaonable size objects this means that wvelengths have to be short.
   My point is that the spectrum is a finite resource. The Ecenomist is simply ignoring well known problems. If they know how to solve them then they should say so.
   

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6.  

   2007 seçimleri

   

   kubilay, Jul 12th, 2006 @ 7:47am

   
   

   Akp 2007 seçimlerinde Türkiye de iktidar olamaz..Türkiyede büyük bir ulusalcılık akımları başlamaktadır...Atatürk devrimlerini kimse hiçe sayamaz ve Vatanseverler iktidara gelecektir.
   TÜM ULUSLARIN BAŞKA ULUSLARI İNCİTMEDEN VATANINI SEVENLERE SAYGILARIMLA....

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