Welcome to SDR PHY for OsmocomBB project


OsmocomBB project provides almost free software GSM mobile station implementation, from Layer 2 to Layer 3. The last non-free parts are: layer 1 and low level signal processing that are implemented in a non-free DSP software which is inside of the hardware platform that OsmocomBB is currently based on (mainly reverse engineered Calypso based mobile phones).

The SDR PHY for OsmocomBB aims to replace these non-free parts through use Software Defined Radio devices and by creating missing software part for tasks such as scheduling, voice encoding/decoding, channel encoding/decoding, burst modulation/demodulation and controlling SDR hardware. In order to achieve this goal the SDR PHY for OsmocomBB brings together OsmocomBB and gr-gsm projects, where the role of gr-gsm is to provide GSM bursts transmission and reception with everything starting from channel coding/decoding being done in OsmocomBB.

Having support for general purpose SDR hardware has additional advantage of not being locked to a single and already obsolete hardware platform. Adding support for a new well documented SDR platform is significantly easier than reverse-engineering mobile phone's hardware and software. This could sustain OsmocomBB project's life even in the absence of hacked mobile phones it is able to run on.

A comparison of Calypso based and SDR based approaches can be found on SDR PHY vs Calypso subpage.


Project status

Please see:

Known limitations (not implemented):

Work in progress:

  • Extend supported hardware list (Soapy?)
    • LimeSDR support (Rx-only for now)
  • GAPK based audio back-end
  • Frequency Hopping

Future plans:

  • AMR (Adaptive Multi-Rate)
  • GPRS protocol stack

More info

What to watch?

Demo (USRP B200, UmTRX, and Nokia 3310):

Date Event Topic Language Speaker Links
29.12.2017 34C3 Running GSM mobile phone on SDR English Vadim Yanitskiy, Piotr Krysik
15-16.05.2018 PHDays 2018 Turning SDR into a GSM mobile phone Russian Vadim Yanitskiy, Piotr Krysik
07.06.2018 PT webinar How to make a GSM mobile phone on SDR Russian Vadim Yanitskiy
26.04.2019 OsmoDevCon 2019 Frequency hopping for SDR based GSM mobile station English Piotr Krysik

What to read?

Topic Author Language Links
How to assemble a GSM phone based on SDR Vadim Yanitskiy Russian
How to assemble a GSM phone based on SDR Vadim Yanitskiy English


The project has support of NLnet Foundation:


Files (1)
nlnet_logo_320x120.png View nlnet_logo_320x120.png 12.5 KB Logo of NLnet ptrkrysik, 09/04/2018 12:41 PM

Updated by fixeria almost 5 years ago ยท 30 revisions

Add picture from clipboard (Maximum size: 48.8 MB)