Software Defined Radio and more

UmTRX is a dual-channel wide-band SDR platform with gigabit Ethernet connectivity, that is developed by Fairwaves and designed to be used as a transceiver (TRX) with OpenBTS and OsmoBTS GSM base stations.

Given its SDR architecture UmTRX can easily be used with many other RF applications, and a combination of FPGA and FPRF (Field-Programmable RF) technology plus the ability to process data on a CPU or a DSP, makes it an extraordinarily flexible platform.

Key features

  • Two full duplex channels that can tune from 300MHz to 3.8GHz 1
  • 50mW to 100mW RF output power 2
  • Integrated TCXO and GPS for frequency stability
  • Thermal sensors for temperature based calibration
  • Optimised for industrial use and high MTBF
  • 1GbE Ethernet connectivity to a computer
  • Power amplifier control 3

1For GSM this means quad-band and dual-ARFCN support.
2For GSM this gives 100-200m coverage with an external duplexer, a small omnidirectional antenna and no power amplifier.
3Only available in UmTRX v2.3.1.

For more details on UmTRX v2.2 see UmTRX v2.2 page.

For more details on UmTRX v2.3.1 see UmTRX v2.3.1 page.


UmTRX v2.2 is open source hardware and Altium Designer schematic and board layout files are made available under the Creative Commons Attribution-ShareAlike 3.0 Unported license. UmTRX v2.3.1 hardware has not been made open-source yet.

FPGA HDL and host driver sources for all UmTRX versions are made available under the GPL v3 license.


UmTRX is part of the Osmocom family of open source projects, and is also a partner project of Myriad-RF. As such it benefits from being part of an ever-growing ecosystem of complementary hardware and software for mobile communications and more.


  • Alexander Chemeris — project leader
  • Andrey Sviyazov — hardware design
  • Jean-Samuel Najnudel — hardware design and manufacturing
  • Josh Blum — FPGA HDL, initial host-side code
  • Sylvain Munaut — various improvements
  • Eric Wild — host-side code
  • Andrey Sviyazov, Sergey Kostanbaev — debugging
  • Andrey Bakhmat — logo, diagrams and photos
  • Andrew Karpenkov – FPGA development
  • Andrew Back — community management


UmTRX uses its own version of the UHD firmware/driver platform and we would like to thank Ettus Research and all those who have contributed to UHD development.

Commercial solutions

UmTRX is a transceiver only. Turnkey base stations and the associated core network servers, along with consultancy services and support, are available from Fairwaves.