Spectrum sensing with USRP2

Description

In this tutorial we'll use the USRPs on the grid for FFT-based spectrum sensing. Each USRP (centered on a frequency with specified bandwidth) will collect data into an OML server for post processing. For details on available USRP2s on the grid, please see ​available USRP2 HW.

Hardware / Software Resources utilized

1. Grid nodes with a USRP2 connect via Ethernet.
2. ubuntu-11-10-gnuradio.ndz: disk image loaded onto nodes. This image has all the precompiled - software required to configure the USRPs and analyze recorded data. The USRP2's interface with the node is already configured.
3. spectrum: application on node to set up & collect data from USRP2 and send to OML server / local file for recording in database file.
4. spectrum_console: application on console to configure & initiate spectrum sense application on node.
5. Octave / sqlite3: for post processing data measured spectrum sense data.

Set up

• To get started first make a reservation on the ​Orbit Scheduler for using the Grid.

• After logging into grid console, make sure all nodes are turned off

  nilanjan@console.grid:~$ omf-5.3 tell -a offh -t system:topo:n210
  

• Verify state of node before continuing. Make sure all nodes are in the POWEROFF state.

  nilanjan@console.grid:~$ omf-5.3 stat
  

• Image nodes

  nilanjan@console.grid:~$ omf-5.3 load -i ubuntu-11-10-gnuradio.ndz -t system:topo:n210
  

• After nodes are imaged, verify that nodes are in POWEROFF state. Otherwise issue the following to turn them off for a reboot

  nilanjan@console.grid:~$ omf-5.3 tell -a offh -t system:topo:n210
  

• Turn nodes back on and verify they are in POWERON state

  nilanjan@console.grid:~$ omf-5.3 tell -a on -t system:topo:n210
  

• Before proceeding, download the ​spectrum console application code to your local directory. This is the application that will invoke the application to configure the USRP on the nodes.

  nilanjan@console.grid:~/UHD/SPECTRUM/w$ wget http://www.orbit-lab.org/raw-attachment/wiki/Documentation/GNURadio/Tutorials/FFTSpectrum/spectrum_console.cpp
  

• Compile the application code.

  nilanjan@console.grid:~/UHD/SPECTRUM/w$ g++ spectrum_console.cpp -lboost_program_options-mt -loml2 -o spectrum_console
  

Usage