10 Mbit/s problem in your network

Mon Feb 18 10:59:26 UTC 2013

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 at swm.pp.se