CREW offers Open Access

CREW is in continuous Open Access phase to support your experiments free of charge!

Final public event & Globecom tutorial

CREW will present its final results at the Wireless Community event (Leuven, Belgium, 29 October 2015, more info) and organises a hands-on tutorial at Globecom (San Diego, USA, 10 December 2015, more info)

CREW PORTAL: access the CREW facilities

Interested in using the CREW facilities?
[Start here] - [Browse by name] - [Overview images] - [Advanced info] - [WTA GitHub].

Control of the USRP remote power switches

Powering the USRPs

In the testbed we have installed two remote power switches which allow us to remotely power each of the USRPs on and off. To access the remote power switches you must first be logged into one of the testbed nodes. Details on obtaining access can be found here. These switches can be controlled through web interface.

Access the switches by navigating to


in the web browser of one of the testbed nodes (again, the power switch interfaces can only be accessed from the testbed nodes). On doing so you will see a similar interface to the following:


The login details are identical to those used to access the nodes themselves. Here, you can power the USRPs for each node on and off. Please remember to power USRPs off when you have finished using them. The positioning of the different testbed nodes as well as the spectrum analyser and signal generator can be found here .

Powering the USRPs via command line/scripts

The remote switch can also be accessed via HTTP Post commands, using a tool such as curl, or equivalent calls in a script or program. Using a UNIX based system with curl installed

curl --data 'P<port>=<command>'

will alter the state of socket <port> according to <command>.

<port> choices are as follows:

    For switch

      * 1 - Node 08 USRP N210 (ETH1)
      * 2 - Node 08 USRP N210 (ETH1)
      * 3 - Node 05 USRP N210 (ETH1)
      * 4 - Node 06 USRP2 (ETH1)

    For switch

      * 1 - Currently unspecified
      * 2 - Currently unspecified
      * 3 - Currently unspecified
      * 4 - Currently unspecified

    <command> choices are:

      * 0 - Switch Off
      * 1 - Switch On
      * t - Toggle state
      * r - Restart

Commands to multiple ports can be strung together using ampersands, as per the following example:

curl --data 'P0=r&P1=r&P2=r'

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