On 09/28/2012 03:25 PM, Eric Fort wrote:
On Fri, Sep 28, 2012 at 12:05 PM, Brian Conrad <[email protected]>wrote:
Walking outdoors in this neighborhood where that tower is over 2 miles
away I don't get any drops while listening. So to the mobile wonks here
why would I get dropouts right at the tower? The phone is an unlocked
Galaxy Nexus and the carrier is 4G or HSPA. Signal was 3 or 4 bars right
there at the tower. This could be useful to know if someone argues back
that the cell tower is right next door and not connecting.
This is actually pretty easy to explain. Think of it this way, start with
a sphere and a single point source of electromagnetic radiation
(technically an isotropic
radiator<http://en.wikipedia.org/wiki/Isotropic_radiator>of say light
or radio waves). This theoretical antenna would take all the
radio wave energy from the cell site and distribute it equally across all
points on a sphere - much of it down into the ground or up into outer
space. This is simply wasted energy (ET never paid for earthbound cell
service and warming the dirt even slightly doesn't pay well either thus
neither form a viable revenue stream for the carrier). This is why they
when you look at most cell sites they use an array of sectoral antennas.
They are called *sectoral* because each antenna in the array focuses it's
energy in only a specific* section* of that sphere that's useful and brings
revenue to the carrier. That said, each section is generally similar in
shape to an oval squatted cone projecting outward from the cell site and
focused at the horizon or maybe with a few degrees of downtilt but not much
more. thus if you are standing right under the tower the radio waves are
probably shooting right over your head off to illuminate some guys cell
phone blocks to miles away from you while the tower he's standing under may
actually be stronger at your location than it is to him standing under it
and vice versa. Hopefully this kinda explains the physics involved in the
RF side of cellular. It's not a software question which is what most of us
here do.
Eric
Thanks. I was wondering it might be the directionality of the
antennas. BTW, I do software too (for almost 30 years) and was looking
for an additional explanation for my Android customers that are not
connecting with Google Play when LVL is authenticating.
--
You received this message because you are subscribed to the Google Groups "Android
Discuss" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/android-discuss?hl=en.
