Spectrum visualization with Fosphor

Description

This tutorial illustrates use of ​RFNoC Fosphor block for spectrum visualization. RFNoC Fosphor block is the FPGA accelerated version of ​gr-fosphor (CPU/GPU version). As any other RFNoC blocks, RFNoC Fosphor can be instantiated on 3rd generation USRP devices, and can be used in conjunction with gnuradio-companion(GRC) on the host computer. This tutorial demonstrates GRC RFNoC Fosphor application on USRP-2974s in [COSMOS testbed wiki:Hardware/sdr/usrp2974] and USRP X310s in [ORBIT].

Running a GRC application on a testbed node requires using graphical user interface(GUI) over SSH. This tutorial also illustrates use of ​MobaXterm and jumphost to setup X forwarding for accessing GUI over SSH.

Prerequisites

In order to access the test bed, create a reservation and have it approved by the reservation service. Access to the resources is granted after the reservation is confirmed. Please follow the process shown on the COSMOS getting started page to get started.

Resources required

2 servers srv3-lg1, srv4-lg1, 2 USRP X310s rfdev3-1, rfdev3-2 and both the Sivers platforms rfdev3-5, rfdev3-6 on COSMOS SB1.

Tutorial Setup

Follow the steps below to gain access to the sandbox 1 console and set up nodes with appropriate images.

1. If you don't have one already, sign up for a ​COSMOS account
2. Create a resource reservation on sandbox 1
3. Login into sandbox 1 console (console.sb1.cosmos-lab.org) with two SSH sessions.
4. Make sure all the nodes and devices used in the experiment are turned off:

   omf tell -a offh -t srv3-lg1,srv4-lg1,rfdev3-1,rfdev3-2,rfdev3-5,rfdev3-6  
   

5. The image sivers_sb1_cosmos.ndz is [baseline_uhd.ndz] with Sivers control software installed. Load sivers_sb1_cosmos.ndz on srv3,srv4.

   omf load -i sivers_sb1_cosmos.ndz -t srv3-lg1,srv4-lg1
   

6. Turn all the required resources on and check the status

   omf tell -a on -t srv3-lg1,srv4-lg1,rfdev3-1,rfdev3-2,rfdev3-5,rfdev3-6
   

   omf stat -t system:topo:allres
   

7. ssh to the nodes, use option -Y for using GUI.

Experiment Execution

Configure MobaXterm for node access

Prepare the node

Run gr-fosphor

gnuradio-companion  /root/gr-ettus/examples/rfnoc/rfnoc_fosphor.grc

root@sdr2-s1-lg1:~# gnuradio-companion  /root/gr-ettus/examples/rfnoc/rfnoc_fosphor.grc
<<< Welcome to GNU Radio Companion 3.7.13.5 >>>

Block paths:
        /usr/local/share/gnuradio/grc/blocks

Loading: "/root/gr-ettus/examples/rfnoc/rfnoc_fosphor.grc"
>>> Done