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OpenLTE: An open source 3GPP LTE implementation
- vvanders 10y agoMaybe a dumb question but I don't see any mention of frequencies/power they use to test in the wiki. I'm a little fuzzy on cell bands but I thought they were all restricted(lots of ham gear has cell bands explicitly locked out).
- boxfire 10y agoSoftware defined radio such as hackrf can use this.
- nobodyshere 10y agoAre you sure? hackrf usually can only provide half-duplex operation, and somewhat full duplex after certain tweaks. Still usb2.0 will be a limiting factor in this case. USRP boards will probably be a lot better.
- meatmanek 10y agoHackRF/USB2 has enough bandwidth to do LTE, particularly since LTE can be configured to use between 1.4 and 20 MHz. I think the lack of full duplex or an FPGA on board would be the major limiting factors.
- chemeris 10y agoAs mentioned above, half duplex of HackRF would be a limiting factor, unfortunately.
- vvanders 10y agoObviously but you need to TX/RX on some sort of frequency otherwise it's not really a radio :). I was just wondering if there's spectrum allocated for experimentation or if you'd be stepping on FCC rules by putting this into practice.
- wolrah 10y agoIf you're running both sides on SDRs you should be able to tweak the frequencies in use. Several LTE bands neighbor and/or overlap amateur radio bands, so adjusting the settings a bit should allow you to move your test operations in to a range that is trivial to gain permission to use. Bands 30 and 40 actually exist entirely within the amateur 33cm band, band 42 overlaps with 9cm, and band 46 overlaps with 5cm. Two of those also overlap with unlicensed spectrum, so there's extra room to play in that no one reasonable expects those bands to be clean anywhere people have electronics. If you have cooperative endpoint devices you could also bodge other more common LTE bands in to amateur frequencies. Band 31 is just a 20 MHz drop away from fitting in 70cm, and cutting down the duplex spacing could make part of band 8 usable in region 2. If you want commercial hardware to work it's probably best to stick to the first group, but if you're doing SDR on both sides and just want to experiment the second group should technically work.
- chemeris 10y agoSpeaking of UEs (aka LTE modems) - there is an open-source implementation add well. See srsUE and srsLTE.
- chemeris 10y agoHackRF can't do it, because it's only half-duplex. But there are plenty of full duplex SDR devices - check out UmTRX and USRP B210. We're also developing a really tiny high performance SDR specifically for LTE - http://XTRX.io http://XTRX.io
- kweks 10y agoThe BladeRF or the upcoming LimeSDR can handle this.
- MrRadar 10y agoLTE in the unlicensed 5 GHz spectrum is coming soon (since the cell companies somehow only just realized that even if it's not pristine spectrum they also don't need to pay billions of dollars to access it) so there will actually be a legal way to use this in the future.
- jeff_marshall 10y agoAny details on handset availability (even rumors)? I'd love to get my hands on a phone with an LTE transceiver that can operate in this spectrum range having an unlocked bootloader on the application processor. Setting up a base station at elk camp and being able to use a regular cell phone instead of a dedicated amatuer or FRS/GMRS transceiver would be very cool.
- MrRadar 10y agoSorry, I don't know when this stuff is coming. In the mean time you could just use a wifi network with a SIP server for voice calls.
- loeg 10y agoHow is that going to work? I thought 5GHz had really poor penetration and attenuation. Will it trash wifi performance?
- MrRadar 10y agoThe cell carriers are mainly planning to use the 5GHz band for small cell indoor deployments (distributed antenna systems). The 3GPP and the Wi-Fi Alliance are going back and forth to ensure that if LTE and Wi-Fi networks are forced to share the same channel that it will at worst degrade the Wi-Fi performance as if there were another Wi-Fi network sharing the channel.
- superkuh 10y ago> ... if LTE and Wi-Fi networks are forced to share the same channel ... at worst degrade the Wi-Fi performance as if there were another Wi-Fi network sharing the channel. All Our Shared Spectrum Are Belong to Us [32c3] https://www.youtube.com/watch?v=9cZxMg8shbA#t=1193 https://www.youtube.com/watch?v=9cZxMg8shbA#t=1193 Unfortunately that's not true in implementation because LTE-U doesn't know or care about the wifi channel announce timings. By piping up whenever it wants to wifi throughput actually degrades more than 70% at minimum LTE-U duty cycle spec (50%) and up to almost completely, ~99% reduction, at max allowed LTE-U duty cycle (90%) spec. No matter what they say this is a spectrum grab and LTE-U will degrade 5 GHz wifi to the point of being unusable.
- rsync 10y agoFascinating that someone is clueful enough to write an open source 3GPP LTE implementation ... yet clueless enough to host it on sourceforge.
- Cyph0n 10y agoHaha that's so damn true.
- turbohedgehog 10y agoJust FYI: https://www.reddit.com/r/sysadmin/comments/4n3e1s/the_state_of_sourceforge_since_its_acquisition_in/ https://www.reddit.com/r/sysadmin/comments/4n3e1s/the_state_...
- deelowe 10y agoHuh. Didn't know this. Thanks!
- djsumdog 10y agoI did read that and I think it was posted here too, but a lot of the comments were on the line of "that's commendable, but the name is already tarnished." Shame really.
- int_19h 10y agoThey did a pretty good job on Slashdot so far, and I think the community response has been rather positive. Hopefully they can turn SF around, as well. GitHub is great, but it's good to have competition to avoid monocultures.
- Teever 10y agoIt is my understanding that they haven't done much at slashdot as the issues with sourceforge were much more pressing. As such I haven't seen any changes occur at slashdot since the take over. I've only seen the slow, steady decline of slashdot continue. Which is unfortunate because every once and a while you see the low UID people make some stellar comments and it reminds me why I stick around despite vastly superior alternatives like hackernews.
- st3fan 10y agoNooooooo why on SourceForge :-(
- CamperBob2 10y agoFortunately it's a .tar.gz rather than an executable, so the amount of harm SourceForge can do is limited.
- Cyph0n 10y agoWe're going to need a SHA-1 or something - they could just rezip the compromised binary.
- phjesusthatguy3 10y agoSourceforge's new owners claim[0] they stopped doing that stuff. I haven't checked to see if it's true but I know it's been discussed on HN before. [0]https://sourceforge.net/blog/sourceforge-acquisition-and-future-plans/ https://sourceforge.net/blog/sourceforge-acquisition-and-fut...
- loeg 10y agoHow so? They could drop an executable named "configure" in the tarball. I don't think they would, but they're not really limited by the format.
- dlmetcalf 10y agoIndeed. People interested in open source for this type of stuff are usually interested in security. Recommend moving the project.
- tlack 10y agoAnyone working on any "ad hoc GSM/LTE" startups, or developed any business models around them? This technology is very interesting but I'm puzzled about what I would use it for.
- blantonl 10y agoProviding GSM/LTE service in extremely remote locations in third world countries spurred the initial implementations of open source GSM stacks. Other business models include intelligence and communications interception.
- ChuckMcM 10y agoInterestingly enough, there are places without any cell phone coverage where being able to enable a small cell site would provide communications. There are also many disaster scenarios where it would be helpful to have such a capability.
- DasIch 10y agoIn how many places would this be legal though?
- wiml 10y agoIt's possible to get permits for temporary operation. People have done this at hacker conferences and at Burning Man for example.
- walrus 10y agoThe Burning Man GSM base station writeup was a fun read: http://openbts.sourceforge.net/FieldTest/ http://openbts.sourceforge.net/FieldTest/
- mkstowegnv 10y agoIndigenous communities in unserved rural Mexico set up their own open source based gsm networks and successfully pressured the central government after the fact to give them permission, and their efforts are spreading virally. https://rhizomatica.org/ https://rhizomatica.org/ http://www.wired.com/2015/01/diy-cellular-phone-networks-mexico/ http://www.wired.com/2015/01/diy-cellular-phone-networks-mex... They have occasional hackathons https://projects.osmocom.org/news/46 https://projects.osmocom.org/news/46
- dperfect 10y agoAre there any legal uses for this (in developed countries) - at least for someone who isn't a major telco?
- jpm_sd 10y agoIn a controlled environment (shielded enclosures), sure. But no broadcasting!
- ubercow 10y agoWhat's the easiest way to setup a shielded enclosure for hacking on something like this with an SDR?
- colechristensen 10y agoIt sounds like a bad response, but if you don't know, you shouldn't be trying. The risks and penalties for screwing up can be enormous and it's not something to take lightly.
- madez 10y agoI think your answer does not only sound bad. Climbing and diving are easily lethal if you don't command your equipment appropriately. Would you recommend someone interested in practicing them to not even try? Nonetheless, the point you make is important. Having said that, giving advise on how to avoid the dangers is what I think to be optimal.
- chemeris 10y agoThere is a hope that 3.5GHz Citizen Band will make it possible for smaller companies to run LTE.
- adynatos 10y agoIf anyone's interested in UE side, I recommend srsUE as a more functional open source implementation of LTE stack. There's also Open Air Interface, which has both Ue and eNB, but is less stable.
- MichailP 10y agoDoes anybody know some nice software radio materials? In form of lectures or lab exercises? I was always wondering about background of people which make feats like this. I have a degree in EE, oriented toward telecommunications but would not be able to produce something similar.
- g_p 10y agoThere is a (free) ebook I found, which takes a practical/exercise based approach to learning about SDRs [0]. It seems to work up from a basic comms background. [0] http://www.desktopsdr.com/ http://www.desktopsdr.com/
- DmitryKlyuykov 10y agoPlease have a look at our “Journey to GSM” series of articles. Our goal here is to introduce and demystify GSM and Software Defined Radio (SDR) technologies. There are only only two parts available so far, but more will come shortly. I’m the author and would be very much appreciate your feedback. Here's the link to the first part: http://umtrx.org/journey-to-gsm-part-1-introduction/ http://umtrx.org/journey-to-gsm-part-1-introduction/
- MichailP 10y agoExcelent tutorials please continue the good work. I like the fact that there is schematics freely available for UmTRX.