Hi everybody,
I'm pretty new to the GSM/UMTS environment and I'm doing some tests. Currently I need to analyze some IoT devices that use 2G network to comunicate via GPRS.
I setup CalypsoBTS to work with 2 old motorola c123, I know that isn't the best way to do that, but I would like to have a cheap solution. I got the setup working with a normal phone and the BTS seems to work correctly (using jolly/testing), but from my understanding it support only GSM calls and SMS and GPRS is not implemented into the transceiver. I'm wrong or this part has not been implemented yet?
If needed to use a GPRS BTS can you suggest the best cheap SDR to use with OsmoBTS? (I saw BladeRF and LimeSDR but I was unable to understand if they are full supported via OsmoBTS)
Thank you in advance.
inode
inode wrote:
If needed to use a GPRS BTS can you suggest the best cheap SDR to use with OsmoBTS? (I saw BladeRF and LimeSDR but I was unable to understand if they are full supported via OsmoBTS)
I am also interested in the answer to this question, but for a completely different reason. I am making my own boards with the Calypso chipset, intended to be a superior alternative to the very cripped Mot C1xx phones, I've already made the first batch of boards and they work nicely (it is my understanding that one of them was demonstrated at OsmoDevCon), and I am currently working on a few outstanding minor hardware issues, as well as professional quality RF calibration. Once I have all of the outstanding hw and calibration issues solved and I build a slightly larger batch, my boards will become available on a retail basis.
However, my FreeCalypso board (FCDEV3B) is intended to serve as a GSM *mobile station* development board, *not* a poor man's BTS. But looking at the traffic on this mailing list, it seems that more people use Mot C1xx phones and OsmocomBB for CalypsoBTS purposes than for GSM work in the Calypso's native MS role, thus I need to have some prepared canned answer to give to those people. My newly made Calypso-based GSM MS development boards will *not* be dirt-cheap like dumpster-sourced Mot C1xx phones, they will probably cost about the same as the full version of bladeRF, and using an expensive board meant for the GSM MS role as a poor man's BTS makes absolutely no sense. Thus when people will inevitably ask me if my FCDEV3B can run CalypsoBTS, I would like to be able to point them to some different product, SDR or otherwise, that is better suited for the BTS role. My question is: which SDR or other BTS product should I recommend to those CalypsoBTS-seeking people?
TIA, Mychaela
Hi inode,
this list is about osmocom-bb, and not about the osmocom projects about networks-side gsm. OsmoTRX, OsmoBTS & Co are discussed on the openbsc@lists.osmocom.org mailing list. Please consider asking your questions there.
On Mon, May 08, 2017 at 06:58:01AM +0200, inode wrote:
but from my understanding it support only GSM calls and SMS and GPRS is not implemented into the transceiver. I'm wrong or this part has not been implemented yet?
I have never used the "calypsobts" hack. But osmo-trx + osmo-bts-trx have support of voice, SMS and GRPS services.
As SMS is using the same signaling channels, this should definitely work even with the CalypsoBTS. For GPRS, you'd need to support the GPRS related coding schemes and an interface to OsmoPCU. Also, given that CalypsoBTS can only provide single (or two?) timeslot, there are a long list of reasons why it would not work straight-forward. But technically also possible to make work.
If needed to use a GPRS BTS can you suggest the best cheap SDR to use with OsmoBTS? (I saw BladeRF and LimeSDR but I was unable to understand if they are full supported via OsmoBTS)
Please raise this (and continue any related discussion) on the other mailing list.
Regards, Harald
baseband-devel@lists.osmocom.org