NI PXIe-5641R Real-Time Spectrum Analyzer

This example code utilizes the Real-Time processing capabilities of the open FPGA featured on the NI PXIe-5641R.

Introduction

The Real Time Spectrum Analyzer is a piece of example code that utilizes the high speed hardware timed processing capabilities of the NI PXIe-5641R IF Transceiver to perform windowing and FFT on the incoming IF data. Normally this is a very CPU intensive process that requires the majority of your PC's processing power and it also introduces a large latency between when the data is actually acquired to when it can be displayed in the appropriate form. Using the in line processing power of the NI 5641R's FPGA optimizes this process and erases most of the processing burden as well as the latency. This example uses an external PXI-5600 down converter to bring the RF signal to an IF frequency that the NI 5641R can acquire. Figure 1 shows the front panel during a single tone acquisition.

Figure 1: Real-Time Spectrum Analyzer User Interface.

Using the Code

This example code is contained in a project named SIGINT Demo.lvproj which holds one FPGA VI that implements the processing of the acquired data. There are two usable host side VIs; one for a normal spectrum acquisition and one that also implements a streaming architecture for streaming the raw data to disk. Figure 2 shows the addition of the Streaming FIFO in the FPGA VI.

Figure 2: FPGA VI with FIFO To Stream Raw IQ Data to Host.

 

To run the VI, simply open the LabVIEW project mentioned above and open either SIGINT Demo (HOST).vi or SIGINT Demo (HOST)_Stream to Disk.vi. Select the resource name for your NI-5641R device and run the VI.

Additional Notes

Note that this VI is hard coded to use the "5600" as it’s down converter resource as seen in Figure 3.

Figure 3: Downconverter Resource Code Seteup.

You may have to open the block diagram and change the down converter resource name to match your down converter.

Requirements

Filename: spectrum_analyzer_demo5641r.zip

Software Requirements

Language(s): LabVIEW

Hardware Requirements

Hardware Group: RF

Reader Comments | Submit a comment »

Can we use this using Measurement Studio?
- Ramprasad Pandranki, CMC Ltd. ramprasad.pandranki@cmcltd.com - Sep 11, 2012

nice!much better if more comments on code
- chen qiang, NISH. - Aug 20, 2010

Can you please also post this vi for Labview 8.6.1? Thanks, Rocio
- Apr 9, 2010