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Re: 10 Mbit/s problem in your network


From: Mikael Abrahamsson <swmike () swm pp se>
Date: Mon, 18 Feb 2013 11:59:26 +0100 (CET)

On Mon, 18 Feb 2013, Owen DeLong wrote:

The reason 5Ghz penetrates stucco better, for example is that the 23cm wavelength is more than 4x the size of the openings in most of the chicken wire used to adhere stucco to walls. The 12cm wavelength of 5Ghz, OTOH, goes through quite nicely.

<http://www.ko4bb.com/Manuals/05)_GPS_Timing/E10589_Propagation_Losses_2_and_5GHz.pdf>

"Aside from large cement blocks and red bricks that displayed somewhat more loss at 5 GHz than at 2.4 GHz (Table 3), losses for all other materials tested were very much the same in both frequency regimes."

Looking at their chart on page 9, I see substantially higher attenuation for cinder blocks, 5% lower attenuation with stucco, and 3x attenuation through red bricks. If concrete (10cm think or even more) is similar to red bricks in attenuation, then that would explain the behaviour I have observed in real life.

The only material that 5GHz had a lot lower attenuation with was diamond mesh.

--
Mikael Abrahamsson    email: swmike () swm pp se


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