Basic AM/FM transmitter in Simulink

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wleonsal
Posts: 4
Joined: Fri Feb 27, 2015 1:51 pm

Basic AM/FM transmitter in Simulink

Post by wleonsal » Mon Mar 02, 2015 3:19 pm

Hello,

Does anybody have a working Simulink model that implements a basic AM or FM transmitter?

Thank you.

jynik
Posts: 455
Joined: Thu Jun 06, 2013 8:15 pm

Re: Basic AM/FM transmitter in Simulink

Post by jynik » Tue Mar 03, 2015 8:29 am

Perhaps you could modify some of the RTL-SDR examples?

I haven't worked with these, but from the documentation and block diagrams, it seems like they'd be a good start...

wleonsal
Posts: 4
Joined: Fri Feb 27, 2015 1:51 pm

Re: Basic AM/FM transmitter in Simulink

Post by wleonsal » Thu Mar 05, 2015 9:45 am

Thank you for the reply jyink.

The RTL-SDR examples are for a receiver. However, I am looking for a transmitter using Simulink and the bladeRF.
I've been following the Simulink examples for the USRP, which can be found here: http://www.mathworks.com/help/supportpk ... k-examples.

However, even with a very simple AM transmitter the spectrum produced by the bladeRF is very "noisy" and "choppy". Here is the Simulink model I am using as my transmitter:
am_tx_model.JPG
Simulink model for AM transmitter
This is how the bladeRF sink block is being configured:
bladerf_config.JPG
bladerf block configuration
Here is the configuration of the sinewave block:
sinewave_config.JPG
sinewave block configuration
Any help or insight will be appreciated
Thank you

jynik
Posts: 455
Joined: Thu Jun 06, 2013 8:15 pm

Re: Basic AM/FM transmitter in Simulink

Post by jynik » Mon Mar 09, 2015 6:21 am

Perhaps try a lower sample rate as a test? What you're describing sounds like discontinuities the MATLAB sink is not keeping up...

For the same hardware configuration, you could try supplying your samples in a CSV format to the bladeRF-cli (using the tx config file=myfile.csv format=csv and tx start commands). You should definitely be able to run at that low of a sample rate.

If the above CLI test works, this would tell us that something about that MATLAB bladeRF sink needs debugging and improvement.

yoshimifuj
Posts: 15
Joined: Wed May 07, 2014 8:59 pm

Re: Basic AM/FM transmitter in Simulink

Post by yoshimifuj » Sun Oct 25, 2015 6:52 pm

It's a simple narrow band FM transmitter with SimuLink (MATLAB 2015b).
Am I too late?
Attachments
bladerfNFMtx.png

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