Hi All, I just want to elaborate it my question is is there is some down link traffic between MS and a testing BTS , let say on ARFCN # 13 and Time slot 3 this traffic channel is non encrypted A5/0 , is osmocom BB or airprob is become to capable to tune to that particular ARFC in this case ARFCN no. 13 and time slot 3 and fetch the traffic channel data process it and convert it to pure voice or encode speech signals ( (CELP) or PCM format ) i specifically request to Harald as he is taking care for airprob also. If these projects need more development to get this extent kindly guide me so that i can start my work and contribute to this project , why taken I have taken this approach is 1) will clarify other aspects and errors in this package to make a working, ready to use package. after wards we will start for transition section. 2) will confirm the feasibility and give all contributor a enthusiasm that we are developing significantly and can get at least any output from moths of hard work 3) will apply the changes and correct for the errors( instability) other developer and contributor will face or report during their voice reception. i feel reception of voice , then transition of voice is very basic requirement of any mobile software, then we can add on other features like channel hoping , cell handovers, other UI features , various multimedia and messaging features.. thanks for your great work and wish to contribute at my best abilities..
--- On Fri, 7/23/10, Dev Purohit devpurohit19@yahoo.com wrote:
From: Dev Purohit devpurohit19@yahoo.com Subject: progress.. To: baseband-devel@lists.osmocom.org Date: Friday, July 23, 2010, 12:49 PM
Hello All, My basic question is related to progress and accomplishment of this project and related project like airprob. 1 if any of these project have reached up to the point where Um or Abis interface traffic can be change to voice or at least to the stage where it can get PCM or ISDN level voice data let say through layer1application we change synthesizer frequency to specific ARFCN, and tune to a specific TS. can it fetch traffic( without encryption, a5/0, testing down link traffic between MS and testing BTS ) channel and after base-band processing can it give voice data (either PCM o, analogue format, digital voice coding) if so what all sections/ applications will involve of this application or if this is possible through airprob so for now. Thank you in advance..
Hi,
On Sat, Jul 24, 2010 at 01:29:23PM -0700, Dev Purohit wrote:
I just want to elaborate it my question is is there is some down link traffic between MS and a testing BTS , let say on ARFCN # 13 and Time slot 3 this traffic channel is non encrypted A5/0 , is osmocom BB or airprob is become to capable to tune to that particular ARFC in this case ARFCN no. 13 and time slot 3 and fetch the traffic channel data process it and convert it to pure voice or encode speech signals ( (CELP) or PCM format ) i specifically request to Harald as he is taking care for airprob also.
For airprobe: you will have to touch the source code to configure it correctly. However, I am aware that somebody has been working on this and will post patches shortly.
For OsmocomBB: We have not worked a lot on TCH yet. Dieter has some preliminary work done and has stated he can see the TCH/F frames of unencrypted full-rate calls in the downlink already. All he needed to do is create the respective multiframe scheduler tables and set the correct DSP task for Full-Rate TCH/F processing (in the source code). If you want this data on the host pc, you will have to create a new HDLC/Sercomm channel and send it over to the PC.
On the PC, you will then run a GSM FR codec and convert it to PCM.
i feel reception of voice , then transition of voice is very basic requirement of any mobile software, then we can add on other features like channel hoping , cell handovers, other UI features , various multimedia and messaging features..
well, that's your personal opinion. To me, voice is relatively insignificant, and it will more or less automatically fall into place once the other parts are finished. Only after we can establish encrypted, hopping channels to a real-world BTS, we will have the need to switch to a TCH...
thanks for your great work and wish to contribute at my best abilities..
Thanks for wanting to help us out!
baseband-devel@lists.osmocom.org
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Dev Purohit -
Harald Welte