Hi Alejandro, 868MHz was better, because the water in the grain absorbs the 2.4GHz electromagnetic waves. And I think the soil contains more water. Could you please inform me about the results of your experiments? I'm intrested in using these radios in bad environment.
Thanks, Andris On Fri, Oct 5, 2012 at 7:19 PM, <[email protected]> wrote: > Dear András Bíró. > > I think probably with 868 MHz was better than 2.4 GHz because the > wavelength is the longest. I was expecting to reach at least 25 m. > > Thanks a lot for your information. > > Yours faithfully, > > Alejandro. > >> Hi Alejandro, >> >> I would except much less. We tried to communicate in grain (corn to be >> exact), and it was less than 1m. Eventually, we used 868MHz, which was >> still really bad, but we could live with that. >> But anyway, you should try it, it's quite simple. >> One more thing: in our tests, it seemed that it was much better if the >> mote was in a bigger box, so its antenna gets farther from the grain >> (but we couldn't use this solution). >> >> Andris >> >> >> On Fri, Oct 5, 2012 at 6:53 PM, <[email protected]> wrote: >>> Dear Hamid Rafiei. >>> >>> Thanks for your answer. >>> >>> What do you think is the maximum distance in the best case? e.g. in 50 >>> m. >>> >>> Sincerely, >>> >>> Alejandro >>> >>> >>>> Hi, >>>> >>>> I believe it all depends on the level of moisture in the soil, in case >>>> of >>>> a >>>> high level of humidity it wouldn't be much at all >>>> >>>> On Friday, October 5, 2012, wrote: >>>> >>>>> Dear all, >>>>> >>>>> Someone know how much is the maximum distance to communicate two >>>>> TelosB >>>>> under the soil using antenna of 5 dBi each one and 2.4 GHz? I mean the >>>>> two >>>>> sensors are "buried" even the antennas as well. >>>>> >>>>> Thanks in advance for any information. >>>>> >>>>> Regards, >>>>> >>>>> Alejandro. >>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> Tinyos-help mailing list >>>>> [email protected] <javascript:;> >>>>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >>>>> >>>> >>>> >>>> -- >>>> -- Sent from my iPhone >>>> >>> >>> >>> _______________________________________________ >>> Tinyos-help mailing list >>> [email protected] >>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >> > > _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
