Re: 10 Mbit/s problem in your network

[Owen DeLong <owen () delong com>]

On Feb 17, 2013, at 4:32 PM, Owen DeLong <owen () delong com> wrote:

> On Feb 17, 2013, at 4:17 PM, joel jaeggli <joelja () bogus com> wrote:
>
> > On 2/17/13 12:18 PM, Jay Ashworth wrote:
> > > ----- Original Message -----
> > > > From: "Owen DeLong" <owen () delong com>
> > > > I think by A you actually mean 5Ghz N. A doesn't do much better than G, though
> > > > you still have the advantage of wider channels and less frequency congestion
> > > > with other uses.
> > > No, my ThinkPad doesn't *do* N, 5GHz or otherwise.  Neither does my Sprint
> > > EVO, nor, as near as I can tell, the Galaxy S4 I'm going to replace it
> > > with this year (though on that one, I'm a tad less certain).
> > >
> > > I'd forgotten that N was dual band, though, yes.  I can't say I've ever
> > > needed the extra bandwidth N provides, personally, though certainly the
> > > hotels we've been discussing might need more to share around.
> > entirely orthonal to the frequency band used spatial division multipluxing as used by 802.11n is generally going to 
> > increase the SNR.
> >
> > so what you get out of A/N is:
> >
> > * more non-overlapping bands and therefore a much easier map coloring problem)
> > * greater attenuation, which implies more limited range, but also less interferance.
>
> Greater attenuation is an oversimplification.  5Ghz penetrates things like stucco and concrete better than 2.4. OTOH, 
> 2.4 gets through trees and moist air better. In dry air and/or a vacuum, they're similar. Neither penetrates humans 
> particularly well, though 5 tends to do slightly better. 
>
> > * with N-mimo higher SNR if you have >= 2 antennas
> >
> > All of those things make the 5Ghz band a more attractive alternative for lots of applications. given that it's 5Ghz 
> > it also requires more power, which is a problem for cellphones, but not so much for tablets and laptops.
>
> OTOH, with 5Ghz, a high-gain antenna is ½ - ⅛ the size (depending on the type of antenna) the size of a 2.4Ghz which 
> also has advantages in portable applications.

Sorry… Hit send prematurely…

An important consideration: A good high-gain antenna helps you with transmit _AND_ receive. More power helps you with 
transmit.

> Owen