UHD, short for USRP Hardware Driver, is the driver and programming interface behind the USRP family of software-defined radios. It is written by Ettus Research, the company that designs and sells those boards, and its source code is published on the company’s GitHub repository under the GPL v3. Ettus Research has belonged to National Instruments since 2010, and NI was in turn bought by the American industrial group Emerson, which closed the deal on 11 October 2023. The ettus.com website still describes Ettus as a brand of NI.
This is a mature project. The repository history shows the version 3.0 tag dating back to 2011, and the current branch has reached version 4.11, released in September 2026. Judging by the releases page, Ettus ships roughly two stable versions a year, each one preceded by a series of release candidates.
What UHD is for
A software-defined radio moves most signal processing out of dedicated hardware and onto a computer. The USRP board turns radio waves into digital samples and back again, while software handles demodulation, filtering and decoding. UHD sits between the two. It finds devices connected over USB or Ethernet, sets frequency, gain and sample rate, loads the right FPGA image and streams samples in both directions with precise timestamps, which is what makes it possible to keep several radios in step.
One driver serves the entire Ettus line-up, from the small USB boards of the B series to the networked X300 and X400 families and the embedded units that run their own Linux system. For those embedded models the repository also includes MPM, a management daemon that runs on the radio itself. UHD exposes a C++ API and a Python API, along with command-line tools such as uhd_find_devices, which lists every radio it can see, and uhd_usrp_probe, which prints a device’s full configuration. It also ships RFNoC, a framework for moving part of the processing into the board’s FPGA so the host CPU has less to do.
Few people actually code against UHD directly. Most reach it through GNU Radio, LabVIEW, MATLAB and Simulink, or through open mobile network projects such as srsRAN, OpenAirInterface and Osmocom’s GSM software, all of which rely on it to talk to the hardware. Its role mirrors that of the bladeRF software at Nuand: each vendor maintains the driver for its own boards, and the two cannot stand in for each other. Analysis tools like SigDigger and Inspectrum come later in the chain, once the signal has been captured.
Who is it for?
UHD is meant for anyone working with a USRP: university labs, telecom research teams, engineers prototyping private mobile networks or experimental radio links, and experienced radio amateurs. Developers get an extensive reference manual at uhd.readthedocs.io and a knowledge base full of application notes at kb.ettus.com.
The limits are clear-cut. UHD only handles Ettus Research hardware and does nothing without a USRP board, which has to be bought separately. Nor is it a receiver application: it shows no spectrum or waterfall, so it needs a companion program such as GNU Radio before you see any result. The installed version also has to match the FPGA images loaded on the board, which means refreshing them with the uhd_images_downloader utility whenever you upgrade. Owners of an RTL-SDR dongle, a HackRF or a bladeRF should look to their own vendor’s driver instead.
Download UHD safely
Three official locations cover everything. The EttusResearch/uhd repository on GitHub publishes the source code and the FPGA images for each release. Windows installers and binary packages live on files.ettus.com, with the newest stable build in the latest_release folder. On Ubuntu, Ettus maintains the ettusresearch/uhd PPA, Fedora users get a dedicated package repository, and on macOS the documentation points to MacPorts. Most Linux distributions also carry UHD in their own repositories, sometimes a little behind the Ettus release.
The driver itself is free. NI does offer a less restrictive licence than the GPL, but only to manufacturers embedding Ettus hardware in volume, and only on request. Because installing UHD on Windows adds USB drivers and requires administrator rights, an installer picked up from a forum or a generic download portal has no business on a lab machine. Stick to the Ettus addresses and check the published checksums for the FPGA images.
Frequently asked questions
Is UHD free?
Yes. The driver is released under the GPL v3 and can be downloaded at no cost for Windows, Linux and macOS. An alternative licence exists, but NI keeps it for manufacturers that build Ettus radios into their products in large numbers.
Does UHD work with radios other than USRPs?
No. UHD is designed for Ettus Research hardware only. Boards from other makers, such as Nuand’s bladeRF, come with their own driver, although an abstraction layer like SoapySDR lets some applications talk to several radio families.
Who publishes UHD today?
Ettus Research, a brand of NI. NI has been part of Emerson since October 2023, inside its Test & Measurement business. Development continues on GitHub, where version 4.11 came out in September 2026.
