🚀 go-pugleaf

On 2010-07-30, DevilsPGD <Still-Just-A-Rat-In-A-Cage@crazyhat.net> wrote:
> In message <daf4565na6ianj22krurgusdul3vq881s9@4ax.com> John Navas
><spamfilter1@navasgroup.com> was claimed to have wrote:
>
>>On Thu, 29 Jul 2010 17:19:05 -0700, in
>><2q4456h5erv7jfegqt0154vtb0uqblfh7g@4ax.com>, DevilsPGD
>><Still-Just-A-Rat-In-A-Cage@crazyhat.net> wrote:
>>
>>>In message <nj3456praioq3mlij37c4bcst6i8n0d6i3@4ax.com> John Navas
>>><spamfilter1@navasgroup.com> was claimed to have wrote:
>>>>>>There is no such advantage, as the citations I've posted make clear.
>>>>>
>>>>>So you're saying that all other things being equal, a 800MHz signal and
>>>>>a 1900MHz signal will penetrate typical buildings and other structures
>>>>>equally?
>>>>
>>>>Read the cited references.
>>>
>>>You didn't cite any... 
>>
>>I did.  Do keep up.  Otherwise, "Google is your friend".
>
> In other words, you don't know, can't answer, have no cites, and want me
> to do the research to prove it?

I can help.  Frequency matters somewhat for indoor penetration, but no
one quite knows how.  If you look at, say, this paper

   http://www.realwireless.biz/publications/papers/ICAP%20pdfs/142.pdf

you'll find this

    Some residential radio penetration studies at 912MHz, 1920MHz and
    5990MHz have shown that penetration loss increases as the frequency
    increases [21]. In contrast to this it has been also reported that
    penetration loss decreases with increasing frequency. These
    measurements were contacted at 35MHz and 150MHz [24], 441MHz,
    900MHz and 1400MHz [14][25] 880MHz and 1922MHz [13], 900MHz,
    1800MHz and 2300MHz [18].

That is, some studies find that penetration loss increases with
increasing frequency (i.e. lower is better) while even more studies
find that penetration loss decreases with increasing frequency
(i.e. higher is better).  The older textbooks I have all take
the latter view (i.e. higher frequencies penetrate better), though
newer textbooks tend to equivocate.  In either case, however,
the penetration losses at 850 and 1900 MHz aren't real different,
and the simple models tend to assume that frequency doesn't matter.

While this seems to surprise people it really shouldn't.  There
are always two possible reasons why one phone loses signal inside
and another doesn't: the building penetration losses could be
different, or the building penetration losses could be the same
but the signal levels outside the building, before the losses,
are different.  I think the latter is the more usual reason.

It is the case, however, that outdoor propagation is effected by
frequency, which I think the first assertion above was also
denying.  If outdoor propagation were independent of frequency
like indoor propagation is assumed to be then, like indoor
propagation models, there would be no frequency-dependent terms
in outdoor propagation models, e.g. Hata and COST Hata here

    http://en.wikipedia.org/wiki/Hata_Model
    http://en.wikipedia.org/wiki/COST_Hata_model

but there clearly are.  The fact that one PowerPoint
presentation neglected to mention this doesn't mean the
dependencies don't exist.

Dennis Ferguson