Working with GNU and Nutaq

Description

This example will demonstrate how to use GRC (GNU Radio Companion) with Nutaq's Zepto SDR.

Set up

To get started, make a reservation on the grid and then load the ubuntu-14-04-64bit-sdr.ndz on two nodes - one node with a Zepto SDR and the other node a USRP. For this example we'll use node20-13 and node20-20 which have a Zepto SDR and USRP, respectively.

user@console.grid:~$ omf load -i ubuntu-14-04-64bit-sdr.ndz -t [[20,13],[20,20]]

Turn on both nodes and verify that the interface to each SDR is configured correctly. Verify connection to Zepto SDR:

ifconfig eth2 192.168.0.1 netmask 255.255.255.0 mtu 9000 up
ping 192.168.0.101

Verify connection to USRP:

ifconfig eth2 192.168.10.1 netmask 255.255.255.0 mtu 9000 up
ping 192.168.10.2

Run the GRC scripts

Download the receiver zepto_rx.grc into node20-13 and open it with GNU Radio Companion.

root@node20-13:~# cd /opt/Nutaq/ADP6/ADP_MicroTCA/sdk/gnuradio/gr-nutaq/examples
root@node20-13:/opt/Nutaq/ADP6/ADP_MicroTCA/sdk/gnuradio/gr-nutaq/examples# wget http://www.orbit-lab.org/raw-attachment/wiki/Tutorials/k0SDR/Tutorial10/zepto_rx.grc
root@node20-13:/opt/Nutaq/ADP6/ADP_MicroTCA/sdk/gnuradio/gr-nutaq/examples# cd ..
root@node20-13:/opt/Nutaq/ADP6/ADP_MicroTCA/sdk/gnuradio/gr-nutaq#sh launch_gnuradio_companion.sh &

A window should pop up similar to the following:

Next download the transmitting side usrp_tx.grc and open with GNU Radio Companion.

root@node20-20:~# wget http://www.orbit-lab.org/raw-attachment/wiki/Tutorials/k0SDR/Tutorial10/usrp_tx.grc
root@node20-20:~# gnuradio-companion

A window should pop up similar to the following:

On both GRC windows click on the execute (side ways triangular) button to start both scripts. On the receiver side and spectrum window should open showing a carrier frequency. The details of the center frequency, power, gain, etc are in the GRC files - tweak a some of the parameters and validate by observing the spectrum.