Luke, Looks like you have the incorrect link for the Openbts.org. The correct link is now http://openbts.sourceforge.net/
/Robert H. [email protected] linux - the best things in life are free On Jan 25, 2010, at 7:42 AM, Luke Kenneth Casson Leighton wrote: > dear olpc devel people, > > i've been doing some research and found a couple of companies with SDR > R.F. front-end ICs. one is 40nm and is so tiny that it will only cost > about $2, mass-produced. also thanks to being in 40nm, the speed of > the (SoC / embedded) ARM9 core is so fast that it's perfectly capable > of handling multiple protocols. as you're no doubt aware, > Software-Defined Radio has been "full of promise" for quite some time > as "The" low-cost transceiver option, but it's only recently that the > speed of embedded ICs has gone up enough and the geometry small enough > to bring the cost down into the affordable range. > > key to making SDR "work" is of course having the software :) but, > i've found a company who already have GSM through EDGE; there's > http://openbts.org and also of course there's the gnu-radio project > which has produced part of 802.11, amongst other things. ( but, > remember: the nice thing about the 2.4ghz and 5ghz bands is that you > don't _actually_ need to do 802.11, you can in fact just use the > entire set of bands to do absolutely anything you want. and, with > SDR, you _could_ do anything you want). > > the neat thing about SDR is that the _same_ solution replaces: > > * a WIFI chipset ($10) > * a GSM chipset ($12 lowest i've found in 100k+ volumes) > * or a 3G chipset ($30 lowest i've heard about in mass-volume) > * a GPS chipset ($6 and that's again an SDR solution, > you need a DSP to translate; $12 for dedicated chipset) > * a WIMAX chipset (haven't even looked this up, but estimate $20) > * a DVB TV chipset (approx $5 and again that's an SDR solution) > * an FM Radio chipset (don't know its cost, don't honestly care!) > > i repeat. all those can be replaced with _one_ i repeat _one_ single > solution, costing roughly... $12, if that. > > issues which need to be resolved: > > * paying for a minimum of 8 40nm 10in wafers (appx 5000 ICs per wafer) > @ $0.50 ea, running the test vectors @ $0.75 ea, packaging @ $0.50 ea > it works out roughly at $2.00 times 40,000. > > * creating the PCB with RF MEMS filters > (http://en.wikipedia.org/wiki/RF_MEMS) and other assorted components, > coax connectors for antenna, the remaining components are going to be > somewhere around $10. > > * license compliance and Certification in the countries in which the > final modem is deployed (remember that if frequencies other than > 2.4ghz or 5ghz @ greater than 100mW are used or 400mW in Hong Kong > then licenses are NOT required) > > even with these issues to be costed out and resolved, i wanted to ask: > > * is the incredible low-cost and flexibility of SDR worth pursuing? > > * is the current Marvell 88688 "proprietary firmware" 802.11 blob > _that_ acceptable / accepted? > > * is the possibility of being able to run an XO up a pole (or placed > at the top of any tall building) and have it _be_ the GSM or WIMAX > base station for an entire town or village and the surrounding > countryside for miles around the kind of thing that is attractive to, > and useful to the aims of the OLPC project, or not? > > also - one thing that also would help to have an answer to : if > answers above turn out to be resounding "yes", what's next? who makes > the decision? > > l. > _______________________________________________ > Devel mailing list > [email protected] > http://lists.laptop.org/listinfo/devel _______________________________________________ Devel mailing list [email protected] http://lists.laptop.org/listinfo/devel
