Re: [gaia] Video about community network using HF band

[Rafael Diniz <[e-mail]>]

Hi Javier, but newQPSK in soundmodem, if my memory does not fail, is way
wide wide than what we are using in HF, 2kHz. We are using OFDM, I'd say
we are closer to Nyquist limit, but of course there is plenty of room
for optimization in the MAC and upper protocol layers.

Rafael

On 3/18/20 6:41 AM, Javier Simó wrote:
> 18 years ago we worked on a HF packet-radio based solution and developed
> improvements  using OFDM newQPSK; getting up to 9600 bits/s. I don't
> know whether I can find the expert who might resemble all the details,
> code, etc, but if you feel it could be interesting I can explore that.
> 
> Best
> 
> Javier
> 
> 
> El 18/3/20 a las 4:31, Rafael Diniz escribió:
>> Gracias Luiz!
>>
>> We carried initial tests of this system in Mexico. The raw throughput,
>> in reasonable propagation conditions, is from 500 up to 4k bit/s. In
>> "real world" tropical region NVIS trx with hundreds of kilometers of
>> distance, with packet protocol and ARQ layers in place, the net
>> throughput ranges from 50 to 500 bit/s, depending on many factors.
>>
>> Abrazo,
>> Rafael
>>
>>
>> On 3/17/20 6:23 PM, Luis Martinez wrote:
>>> Parabens Rafael ! 
>>> It is wonderful, we are discussing a project like that in Mexico. Can
>>> you share what is the speed you are able to achieve ?
>>> Obrigado.
>>> Luiz
>>>
>>>
>>> On March 17, 2020 at 1:37:42 PM, Rafael Diniz ([e-mail]
>>> <mailto:[e-mail]>) wrote:
>>>
>>>> Hi all,
>>>>
>>>> Here is the link of our latest developments about HERMES[1]:
>>>> https://vimeo.com/398331581
>>>>
>>>> Cheers,
>>>> Rafael Diniz
>>>> Rhizomatica
>>>>
>>>> [1] https://www.rhizomatica.org/hermes/
>>>>
>>>> _______________________________________________
>>>> gaia mailing list
>>>> [e-mail] <mailto:[e-mail]>
>>>> https://www.irtf.org/mailman/listinfo/gaia
>>
>> _______________________________________________
>> gaia mailing list
>> [e-mail]
>> https://www.irtf.org/mailman/listinfo/gaia
> -- 
> 
> 
> *Francisco Javier Simó Reigadas*
> 
> *Profesor, Director de la ETSIT*
> 
> *Dep**t. Teoría de la Señal y Comunic. y Sist. Telemáticos y Computación*
> 
> Universidad Rey Juan Carlos
> 
> Campus de Fuenlabrada(Madrid), España
> 
> Teléfono: 91 4888167
> 
> [e-mail] <mailto:[e-mail]>| www.urjc.es
> <http://www.urjc.es>| @URJC |
> 
> 
> 
> 
> _______________________________________________
> gaia mailing list
> [e-mail]
> https://www.irtf.org/mailman/listinfo/gaia
>