Changes between Version 3 and Version 4 of Tutorials/k0SDR/Tutorial00b

Timestamp:

Jul 26, 2021, 7:25:39 AM (3 years ago)

Author:

mpk2138

Comment:

—

Tutorials/k0SDR/Tutorial00b

@@ -122 +122 @@
 {{{root@node1-X:~# sudo sysctl -w net.core.rmem_max=24862979}}}
 
-=== Building the GNU Radio Flowgraph ===
+=== Building the GNU Radio Flowgraphs ===
 ''See the troubleshooting section below for a common error and how to fix it.''
+
+==== Transmitter ====
 
 Start GNU Radio on {{{node1-1}}}:
@@ -134 +136 @@
  || [[Image(x310_sb2_tx_flowgraph.png, 600px)]] ||
 
-Here, the "Signal Source" generates samples for a 1 MHz cosine wave at the flowgraph sample rate, in this case 10 MHz. The samples then go into a "UHD Sink". The "UHD Sink" is what takes the signal samples generated in GNU radio and sends them to the USRP for transmission. Samples are generated
-
-When creating this flowgraph, you will need to set values for {{{samp_rate}}} as well as parameters in each of the blocks. Double clicking on a block will bring up an editor for all parameters that a block uses. See below for the parameters used in this experiment for each block:
-
- ||||||Figure 1: Gen-2 FDE Canceller Boxes in COSMOS Sandbox 2 ||
- || [[Image(Gen2Architecture.jpg, 280px)]] || [[Image(Gen2Ceiling.jpg, 375px)]] || 
- || (a) The FlexICoN Gen-2 RF Canceller Box and antenna  || (b) Rack-mounted, reorganized Gen-2 RF Canceller Box ||
+Here, the "Signal Source" generates samples for a 1 MHz cosine wave at the flowgraph sample rate, in this case 10 MHz. The samples then go into a "UHD USRP Sink". The "UHD USRP Sink" is what takes the signal samples generated in GNU radio and sends them to the USRP for transmission. 
+
+You can add blocks by clicking the magnifying glass to open a search bar and then search. Drag the block from the list into the flowgraph or double click and it will show up. To make connections, click on a blue tab and drag to another one.
+
+You will need to set values for {{{samp_rate}}} as well as parameters in each of the blocks. Double clicking on a block will bring up an editor for all parameters that a block uses. See below for the parameters used in this experiment for each block:
+
+ ||||||||Figure 2: Transmitter Flowgraph Parameters ||
+ || [[Image(x310_sb2_tx_usrp_sink.png, 280px)]] || [[Image(x310_sb2_tx_signal_source.png, 280px)]] || [[Image(x310_sb2_tx_options.png, 280px)]]
+ || (a) UHD USRP Sink  || (b) Signal Source || (c) Options ||
+
+Note that in the USRP Sink, we are setting the address to be 192.168.40.2. This is the same address we were setting up the network card interface to be able to communicate with earlier.
+
+After all of these parameters have been entered, press the green play button. It will prompt you to save the flowgraph, you can save it in the default directory with the filename {{{x310_tx.grc}}}.
+
+When the flowgraph runs, it should after some seconds open up a new GUI window with nothing on it. This is OK, it is blank simply because we used no GUI blocks. To stop it running, simply close this window.
+
+==== Receiver ====
+
+Start GNU Radio on {{{node1-2}}}:
+
+{{{root@node1-2:~# gnuradio-companion}}}
+
+We want to build a flowgraph that looks like the following:
+
+ ||||Figure 3: Transmitter Flowgraph ||
+ || [[Image(x310_sb2_rx_flowgraph.png, 600px)]] ||
+
+Instead of a USRP Sink, we have a USRP Source. This gives us samples received by the radio receiver at the specified sample rate of 10 MHz. We then feed these samples into a "QT GUI Frequency Sink", which will allow us to see the frequency spectrum of the signal we are receiving. We need the following parameters set up:
+
+ ||||||Figure 4: Transmitter Flowgraph Parameters ||
+ || [[Image(x310_sb2_rx_usrp_source.png, 280px)]] || [[Image(x310_sb2_rx_options.png, 280px)]] ||
+ || (a) UHD USRP Source  || (b) Options ||