Re: [Discuss-gnuradio] Help required for dpsk_loopback.grc

[Tom Rondeau]

On Wed, Mar 4, 2015 at 5:18 AM, SACHIN REGUNDWAR <address@hidden> wrote:

Dear All,

I am very new to GNU Radio and currently trying to explore the example grc blocks available with the package. For example, I tried to execute the example given in the example folder as  "dpsk_loopback.grc" (/home/ubuntu/examples/digital/demod/dpsk_loopback.grc). I have following doubts:

1. There is no readme or document available which can explain about the total block or example in detail. Can I get any tutorial/document which will give complete info about all such examples?? i.e.Each grc example file to be explained in detail. If any such details are available, kindly give me the link for the same.

Nope. The examples show you how to use the various blocks but don't have write-ups on their own. You can find what each block does in the manual:

gnuradio.org/doc/doxygen

 

2. In the subject example, there is a signal source which is generating a cosine wave from 500Hz to 5KHz. This cosine wave after the throttle block is fed to packet encoder. Here, what is the role of packet encoder?? In the packet encoder block properties there are many fields like "samples/symbol", "bits/symbol", etc. These fields are generally related to data, not the analog signal which is fed to it. How does the packet encoder take cosine wave and use the fields like samples/symbol and bits/symbol??? Do we have any document which will explain in detail about all such blocks???

It is a bit strange, I'll admit, but that sine wave is just digital samples that are shaped like a sine wave. So passing them through as digitally modulated samples is the same as passing any value.

 

3. I want to analyze the output of packet encoder. How is it possible?? Which block will you suggest to analyze the output???

There are plenty of display widgets (QT or WX) that you can use here. Or dump it to a file and analyze the raw bytes anyway you know how.

 

4. As I am very new to the GNU field and I quite poor in software domain, I would like to get some help in the beginners level. Please provide me any link, if it is available.

Regards,

SACHIN M. REGUNDWAR
Hyderabad, India.

To get a good feel for GNU Radio:

http://gnuradio.org/redmine/projects/gnuradio/wiki/Guided_Tutorials

And for other reading:

http://gnuradio.org/redmine/projects/gnuradio/wiki/SuggestedReading

Tom