4.3 Loading a Waveform

The 0.6.2 release supports two options for loading a waveform:

1. The command-line wavLoader.py script discussed below
2. The graphical tool ALF described in Section 6

Directions here are for running the OSSIE demonstration waveform, ossie_demo. The demonstration waveform simulates a very basic QPSK communication system. It consists of three components: a transmitter, a channel, and a receiver. The transmitter generates bursts of 512 QPSK symbols that are sent through an AWGN channel and decoded by the receiver. The number of errors per burst will be printed out on the screen while the waveform runs. To run another waveform, substitute ossie_demo with the name of your waveform.

Load the waveform using wavLoader. In a terminal window, execute:

 $ cd /sdr/waveforms/ossie_demo
 $ wavLoader.py ossie_demo_DAS.xml

One or more SAD files (ending in .sad.xml) will be listed. To load the waveform, enter the number that corresponds to ossie_demo.sad.xml. If this file is listed twice, choose the first listing (//waveforms/ossie_demo/ossie_demo.sad.xml).

Finally, enter s to start the waveform.

The terminal window in which nodeBooter was started will now contain the output of the demonstration waveform. The lines will update with output similar to this:

 RxDemo errors:  X  / 1024

X denotes the number of QPSK bit errors out of 1024 that have been detected by the RxDemo component. The terminal should look like this:

Congratulations! You have just run the QPSK demonstration waveform for version 0.6.2. From here you may be interested in learning how to create your own waveforms and components using the OSSIE Waveform Developer as described in the following section.