Anthony - I almost labelled the idea an LPFM mesh but then I thought it wouldn't have to mesh, ie the nodes would not need to talk to each other (provided each host had an internet uplink) so maybe its a somewhat different topologyHol - In principle I totally agree with you about such a distribution of radios simply blocking spectrum from being used for other purposen -- but along the same sort of moral-political lines that justify pirate radio in the first place, the spectrum of sidebands in question here (FM/LPFM) is, from what I infer, already not technically-legally available to the public..? So I don't see how in this particular case, how engaging in an experiment like this cannabalizing a frequency etc would be that deprivational for the public at large.. again, just as with 'normal' pirate/community radioAlso - this is a really dumb question but in terms of interference, I actually have no idea what sort of interference results when two coverage-adjacent radios are broadcasting the exact same signal? Does it make any difference if they'd both be broadcasting the same signal? I should remember this, since I actually took one of those AARL tests wayyy back when (and I think I am technically FCC licensed, at least for certain spectrums like SSB? Can't exactly remember..i should have a certificate somewhere) but:Seems like one should be able to rewire existing off-the-shelf audio-in FM transmitters for whatever frequency we want, and somehow make the signal a bit stronger to cover a block or whatever, instead of only one's house..Prolly a dumb idea, just a lark - I know nothing of 'cognitive radio' but I'd love to talk to you more about it, anthony!DavidOn Mon, Nov 4, 2013 at 1:32 PM, Anthony Di Franco <di.franco@gmail.com> wrote:
Software-defined radio and the broader embracing paradigm of cognitive radio are still topics of active research on fundamental issues and they are both built out of the practice of negotiation among participants in a communication about the means of communication (what part of spectrum to use and what encoding mainly).
They were in part motivated by desire to work around existing fixed uses of spectrum (like FM audio broadcasts) in a non-interfering way, but wouldn't really be useful to transmit to existing receivers that can't participate in the negotiations they involve.
Good stuff to build into a mesh architecture but heavy-duty to implement or even play with without hardware and software tools that are currently mostly ad-hoc and specialized and usually fairly obscure and expensive. This may be changing a lot fairly soon because imminent generations of cell phones are due to incorporate pretty good software-defined radio, I recall hearing somewhere.
The only simple hack along the same lines I can think of is to choose a frequency to transmit FM audio on, detect interference from other transmitters on that frequency, and stop transmitting in that case. I don't see the usefulness of doing that in this context though.
http://lists.sudoroom.org/listinfo/sudo-discussOn Mon, Nov 4, 2013 at 1:17 PM, Eddan Katz <eddan@sudoroom.tv> wrote:
I've read about software-defined radio making interference problems negligible (can't find anything in particular at the moment - but most coming from the IEEE publications).
I'd be interested whether others (a) understood if this is true; (b) knew of affordable SDR equipment; and/or (c) thought this would solve the problem.
Sidenote: While streaming-only radio stations do not have to deal with spectrum licensing issues, their Internet presence make broadcasting anyone else's copyrighted content a complicated and either expensive or risky endeavor.
sent from eddan.com
On 2013-11-04 12:52, Hol Gaskill wrote:
it does seem philosophically better to provide content on an opt-in
basis via existing RF links than to simply radiate it in every
direction and block that portion of the spectrum from other uses
This sounds a lot like the mesh networking projects, which move awayOn Nov 4, 2013 11:31 AM, "David Keenan" <dkeenan44@gmail.com [23]>
from broadcasting as fundamental and rebase broadcasting in a
peer-to-peer context, and are already oriented the right ways
technically and with respect to regulations for those goals.
wrote:
I find myself most sympathetic to Naomi's position - although I do
still think FM as a medium has some romance and cool left in it, I
don't know that it's actually worth it, given the cost and effort.
Completely naiive riffing follows, but -- since decentralizing
information and the means of production are (for me) integral to
freeing information / culture.. if one wanted to recolonize the
airwaves, I wonder if it might be possible to simply distribute
LPFM?
Ie, give people a small appliance that transceives internet radio
into LPFM or way lower-power radio, ie just for their block /
neighborhood / whathaveyou.. A device that doesn't take a whole
lot of power, that is innately not geographically bounded, and can
become a diaspora of signal. And not necessarily legal but
decentralized and dispersed.. if enough folks did this in
aggregate in a given neighborhood or community, could that
collectively function coverage-wise as a single relatively strong
broadcast / antenna?
Has anyone tried anything s