You also have to add in receiver senseivity/antenna gain on each band.
Your test is still good because it is testing the raw coverage for that
phone model to a single tower over two bands. It may be that the
phone is optimized for 1900 Mhz and will give equal results on both
bands.

The other Bill

"g" <wh@t.me.worry> wrote in message
news:455802b5$0$34492$742ec2ed@news.sonic.net...
> decaturtxcowboy wrote:
>
>> Actually, reading the dB scale wasn't necessary. Most importantly we
>> did a side by side comparison from same cell tower location and similar
>> preforming phones. So the only significant variable would be the
>> propagation difference of the two bands (assuming similar radio
>> performance).
>
> Yes, the real test is to see where communications stops, since power
> control and a host of other things get into the act and make it very hard
> to decipher what is truly going on as you are anything less than last-gasp
> comms.
>
> Do recognize though that this still isn't a propagation comparison until
> you are sure that you know the ERP of each site (in the pilot or whatever
> is being measured by 'bars') and the effective aperture of each handset
> antenna.
>
> We should note also that there is an implicit assumption of the same
> noise+interference level here as well.
>
> Effectively then you are still making an absolute power measurement by
> comparing the point at which the Carrier/Noise ratio falls below that
> required for the modulation scheme, with the assumption of constant, known
> noise floor (KT.
>
> All in all this is a pretty rough way to determine frequency related
> propagation differences. It's a lot more accurate and ultimately easier to
> do it with a specialized system, which is what the better models reflect.
>
> g