Software Defined Radio with USRP N200 and LabVIEW (GUIDE)
As a part of my electronic engineering degree I have decided to look into the world of Software Defined Radios, a complicated but very powerful tool.
Software Defined Radios, SDR in short, is in short a software-based radio platform, making it possible to program the RF transmissions schemes and updating them on the fly if necessary, a bit similar to what we in the digital world know as FPGA’s. This allows end-products to redefine their radio needs, such as when sending a satellite into orbit where it would be impossible to update the RF hardware platform to support other radio protocol and schemes.
To get familiar with the SDR’s I decided to work with a basic USRP N200 module which is supported by LabVIEW and other tools, eg. GNU Radio, and write a detailed report about my progress and discoveries (see the bottom of the post for a link to the report).
The N200 module is controlled over an Ethernet interface, which is also used to exchange (transmit and receive) the so called IQ samples when they have been converted by the analog RF frontend.
In the video below I demonstrate the use of a Software-Defined radio setup with two USRP N200 modules programmed in LabVIEW programmed with an AM modulation and demodulation scheme.
The modules are programmed and tested thru LabVIEW where a graphical interface allows me to transmit a single tone signals or an audio-file from one SDR unit to another for.
The programming of the USRP N200 is done thru the graphical block-based programming environment within LabVIEW, supporting both the IQ signal generation and reception (decoding). To give you an idea of the programming environment, the image below contains the modulation part of the audio-file modulator example shown and described within our report.
Further details and a comprehensive guide and tutorial on how to get started with the USRP N200 modules, from the very beginning with the basic setup and configuration followed by the programming thru LabVIEW, can be found in the following report:
The project ressources in terms of the LabVIEW project files can be downloaded here: usrp_am_modulation.zip