Changes between Version 10 and Version 11 of Tutorials/k0SDR/Tutorial00

Timestamp:

Aug 29, 2012, 6:27:43 PM (12 years ago)

Author:

nilanjan

Comment:

—

Tutorials/k0SDR/Tutorial00

@@ -285 +285 @@
 
   Two distinguishable peaks should be present in the frequency spectrum of the receiving node. The peak at 5001 MHz corresponds to the 1 MHz sine wave generate and the smaller peak at 5000 MHz corresponds to carrier signal. This can be a very rough estimate of the carrier signal strength of about 75 dBm.
-
 {{{
                                                                                  :.
@@ -319 +318 @@
 }}}
 
-= Next: Capture waveform and record to file & add time-domain plot of waveform =
+== Capture waveform and record to file & add time-domain plot of waveform ==
+
+ * Now record the received signal to an OCTAVE / MATLAB file.
+  From node1-1 transmit a waveform with the following attributes
+{{{
+root@node1-1:~/uhd/host/build/examples# ./tx_waveforms --wave-freq 1e6 --wave-type SINE --freq 5000e6 --rate 8e6 --ampl 0.5
+}}}
+
+  On node1-2, use the rx_sample_to_file utility to dump the received samples into a file.
+{{{
+root@node1-2:~/uhd/host/build/examples# ./rx_samples_to_file --freq 5000e6 --rate 8e6 --type float
+}}}
+
+  The samples will be recorded into the file ''usrp_samples.dat''. Upload this file into octave and plot the time-domain samples.
+  On node1-2, start up octave
+{{{
+root@node1-2:~/uhd/host/build/examples# octave
+GNU Octave, version 3.2.4
+Copyright (C) 2009 John W. Eaton and others.
+This is free software; see the source code for copying conditions.
+There is ABSOLUTELY NO WARRANTY; not even for MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  For details, type `warranty'.
+
+Octave was configured for "i686-pc-linux-gnu".
+
+Additional information about Octave is available at http://www.octave.org.
+
+Please contribute if you find this software useful.
+For more information, visit http://www.octave.org/help-wanted.html
+
+Report bugs to <bug@octave.org> (but first, please read
+http://www.octave.org/bugs.html to learn how to write a helpful report).
+
+For information about changes from previous versions, type `news'.
+
+octave:1>
+}}}
+
+  From the Octave prompt verify received signal in the file
+{{{
+octave:5> c=read_float_binary('usrp_samples.dat');
+octave:6> creal = c([1:2:length(c)]);
+octave:7> cimage = c([2:2:length(c)]);
+octave:8> subplot(211) ; plot(creal(100:230)) ; title('real') ; axis([0 140 -0.010 0.010]) ;
+octave:9> subplot(212) ; plot(cimage(100:230)) ; title('imag') ; axis([0 140 -0.010 0.010])
+}}}
+
+ A window should pop up from the 
 
 == Troubleshooting ==