Generate Square wave and Sine wave with variable frequency for USRP

[josephkirmani]

Can any one guide me how to create a VI which gives Square wave and Sine wave with variable frequencies and also I want to use USRP to transmit these waveforms? So can any one guide me how can I do that ? I will really appreciate your help in this regard.

[Sarah_Y]

Hi waqash21,

When you say variable frequency, do you want to vary the frequency of the sine wave, or the carrier frequency of the USRP?  There is a shipping example that lets you do both--niUSRP EX Tx Continuous Async Reconfig on the Fly.vi.  You can adjust the frequency of your sine wave by adjusting the tone frequency.  You can adjust the frequency that your USRP is transmitting at by changing the carrier frequency.  Please note, the tone frequency will not update on the fly.  This is because the sine wave is only being generated once at the beginning of the VI.

Can you tell me a little more about your application?  Why do you want to send a square wave to your USRP?

[josephkirmani]

Dear Sarah,

1) I want to vary the frequency of the Sine/Square wave.

2) I want to drive the LED using Square wave. Is there any example VI available. If not can you guide what changes do I need to make in the file you mentioned ?

Best Regards

JK

[josephkirmani]

Dear Sarah,

Can you please guide me how to generate square wave using LabView for USRP ? Also can I connect oscilloscope with USRP to see the generated waveform ? 

[Wan-L]

Search in quick drop for "sine waveform.vi" and "square waveform.vi". These VIs generate arrays storing samples of waveform you want to specify. 

I found another forum post from you asking if the USRP can be made into a function generator. I think what you want to do is transmit a message signal that is the function to be generated (sine, square, triangle, etc). If thats the case, you will need the modulation toolkit to FM or AM modulate the output of the sine waveform.vi into I Q pairs for the USRP write VI