The SMOS project / 72h civil emergency communications system

Kalle Pietila kalle.pietila at gmail.com
Thu May 17 10:32:31 UTC 2012


Hi Alexander,

yes I'm aware that a BTS would need to be transmitting all time, which
is not best starting point for being power-efficient. However good to
get confirmation that multi-ARFCN can be avoided. I mailed to BB list
as I see this part as most probable technical show stopper for this
initiative. The chip designs seem to be targeted for mobile broandband
applications with all that unnecessary functionality at a silicon
screaming for more power. Also proprietary L1 can be a major problem
when cost of BTS module needs to be kept minimal (modules getting
lost, damaged, stolen, or vandalized) and also this stuff would need
to be affordably available for the developers. Actually, SMS-only
supporting base-stations could be a first viable application for an
open L1 implementation?

We're though about balloon raising the antenna up and also flying
drones with BTS as payload. Flying or floating might work well on
still weather, but probably not at all under heavy winds. Not sure
whether this would acceptable shortcoming for the imaginary
"customer". Balloon-approach might just have worked better in case
Haiti, I see the point.

Thanks for hinting the OpenBTS mailing list, I'll drop a line there too.

Best Wishes,

   Kalle Pietilä

On Thu, May 17, 2012 at 10:17 AM, Alexander Chemeris
<alexander.chemeris at gmail.com> wrote:
> Hi Kalle,
>
> BTS has to transmit constantly on it's main ARFCN, no matter do you
> make calls or just send SMS. So while you operate a single ARFCN you
> can't save power by employing only SMS. On the other hand, for SMS a
> single ARFCN would be enough to provide a good capacity, while support
> for calls would require a multi-ARFCN config which would be quite
> power hungry.
>
> Have you thought about using a balloon for carrying a BTS instead of
> dropping to a ground? This would give you much better coverage easily
> then on-the-ground installation.
>
> PS I think this would get more responses from the OpenBTS mailing
> list, then from OsmocomBB mailing list, as this is definitely a
> network-side question.
>
> On Wed, May 16, 2012 at 10:28 PM, Kalle Pietila <kalle.pietila at gmail.com> wrote:
>> Dear baseband enthusiasts,
>>
>> on SMOS project we had this crazy idea for catastrophe communications
>> in which cellular base stations would be miniaturized enough to be
>> airdropped into disaster zones. We felt that this might
>> be possible if all functionality except SMS was stripped from the base
>> stations (hence SMOS, SMS Our Souls). Most ideally such technology
>> would come in near cellphone size (excluding batteries), something
>> like osmocom's earlier "Phone acting as BTS" hackwork.
>>
>> We did not have the guts nor skills to start doing this by ourselves,
>> so we just published our findings and studies under Creative Commons
>> BY license. As we wish to keep this idea open to everyone, our
>> web-documentation would benefit on this regard from some more in-depth
>> HW-related analysis and suggestions  (our team fell short on this
>> area). Once it's all published, it cannot be patented. I personally
>> see some humanitarian & karma-improving angle in doing it this way.
>> Helping human kinds in disaster should not be bound by patent laws.
>>
>> So I'm asking for constructive criticism and also offering possibility
>> to write some informal blogs about your views on
>> www.zygomatica.com/smos (with our team's editorial support) . At the
>> same time it should be noted that such technically oriented blog
>> writings at my friends' site zygomatica.com would likely reach 50
>> readers at most. To put it more nicely, reaching the widest possible
>> audience is not our focus here anyways.
>>
>> My technical vision is presented at
>> http://www.zygomatica.com/wp-content/uploads/2012/04/SMOS6-Technical-goals-System-requirements-v10.pdf
>> .. and the full list of formal documents at end of
>> http://www.zygomatica.com/smos/ . The other provided background
>> material might be even more valuable to those that start considering
>> this idea more seriously.
>>
>> So, For instance, can stripping  down the functionality just to
>> supporting SMS delivery bring down the power consumption in any
>> significant manner?
>>
>> Thanks and regards,
>>
>>  Kalle Pietilä
>>
>> P.S. Mailed to this list as suggested by Harald.
>>
>
>
>
> --
> Regards,
> Alexander Chemeris.
> CEO, Fairwaves LLC / ООО УмРадио
> http://fairwaves.ru




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