USRP2900 - RX Spectrum Analyzer

[Thierry.LE_GALL]

Overview

Spectrum Analyzer using USRP2900 and LabVIEW Communications System Design Suite 2.0. Useful to locate available received signals (RX) before going further in the implementation of demodulation processing in real-time in the loop. Also

could be useful to learn spectrum management and spectrum monitoring using USRP2900.

Description

This is a *.gvi to implementing spectral analysis of received signals from USRP2900 with VHF/UHF antenna. The *.gvi plots IQ signals (temporal view) and the I ar Q signal spectrum (frequency view)

Hardware and Software Requirements

USRP 2900 + VHF/UHF antenna
LabVIEW Communications System Design Suite 2.0
PC host / Window7 SP1

Steps to Implement or Execute Code

1. Plug the NI-USRP 2900 to the host (USB3)
2. Launch NI-USRP Utility and check USRP2900 conexion to the host
3. Launch LabViEW Communications System Design Suite 2.0
4. File/New/Project
5. Navigation Pane : Untitled Project -> right clic + Add File...
6. Add File : rx_spectrum_usrp2900.gvi
7. Run (0 errors, 1 warnings).

Additional Information or References

[singh8865]

how we can sense the range of frequency ie 935MHz-960 MHz in your vi

[Thierry.LE_GALL]

Hi Singh,

960 - 935 = 25 MHz bandwidth, so you need to set the RX IQ rate (fe) to 25 MHz at least

and

(960 + 935) /2 = 947.5 MHz; so you need to set the RX carrier frequency (f0) to 947.5 MHz

Regards,

Thierry

[john308]

Hi Thierry,

 I want to sense the range of frequency ie 70MHZ-110 MHZ. As you said,I set the RX IQ rate  to 40 Ms/s and  set the RX carrier frequency  to 90MHZ.

But an error occurred.

john

[john308]

Here are my VI program，

block diagramfront panel

regards，

John

[singh8865]

problem in syncing data with 4.615mshello Sir in above code can we collect 1000 sample in 4.615ms  i am not able to sync my execution timing with usrp2920 execution code

eg.

in 4.615ms i want to take 1000 samples

so in 1s=1000/4.615m samples=216684

in 1minute=2166848*60= 130010083 

i am saving tdms file within while loop but it is just giving around 60000000(almost less than half samples) why this is happening sir.....

problem in sync