Implementation of a Simple FM Receiver in GNU Radio
From Ettus Knowledge Base
Contents
Revision History
| 2016-05-01 | Neel Pandeya | Initial creation |
Application Note Number
AN-5501
Introduction
Implementation of a Simple FM Receiver in GNU Radio
Authors: John Smith and Jane Smith
Organization: Ettus Research
Last Modified Date: 2016/04/15
Overview
In this application note, a Universal Software Radio Peripheral (USRP™) N200/N210 and a WBX daughterboard is used with GNU Radio to build a simple FM receiver. The intent of this example is to:
- Teach some basic DSP and RF concepts including: filtering, demodulation, and sample rate conversion.
- Show how to build graphical applications with GNU Radio Companion
- Illustrate the simplicity of the software tools that can be used with the USRP product family.
Requirements
- USRP with compatible daughterboard to receive 88-108 MHz
- GNU Radio
- UHD
Blocks
UHD Source Block
- Configures USRP
- Receives data stream from USRP
FFT Sink
- Display Fast Fourier Transform of data stream
Low Pass Filter
- Apply low pass filter to data stream
- Optional: Decimation or Interpolation
WBFM Receive
- Demodulates Wide Band Frequency Modulated signal from data stream
Rational Resampler
- Decimate or Interpolate data stream to desired sample rate
Audio Sink
- Audio hardware interface
- Optional: Decimate Audio Rate
Wav File Sink
- Save data stream as WAV file type
WX Widgets
- Textbox - Input field
- Slider - Adjustable slider
- Notebook - Assign Widgets/GUI Sinks to tabs within flowgraph
Variable
- Creates variable within flowgraph
Video
https://www.youtube.com/watch?v=KWeY2yqwVA0
You can download the sample GRC file here: http://files.ettus.com/app_notes/fm_rcvr/fm_example.grc
