Tagged: MATLAB

Software Defined Radio for Engineers: Free University Level Text Book with PlutoSDR Examples

Analog Devices has recently released a new text book for free called "Software-Defined Radio for Engineers, 2018". This is an advanced university level text book that covers communication systems theory as well as software defined radio theory and practice. The book uses the PlutoSDR as reference hardware and for practical examples. The PlutoSDR is Analog Devices $150 RX/TX capable SDR that was released about a year ago.

The objective of this book is to provide a hands-on learning experience using Software Defined Radio for engineering students and industry practitioners who are interested in mastering the design, implementation, and experimentation of communication systems. This book provides a fresh perspective on understanding and creating new communication systems from scratch. Communication system engineers need to understand the impact of the hardware on the performance of the communication algorithms being used and how well the overall system operates in terms of successfully recovering the intercepted signal.

This book is written for both industry practitioners who are seeking to enhance their skill set by learning about the design and implementation of communication systems using SDR technology, as well as both undergraduate and graduate students who would like to learn about and master communication systems technology in order to become the next generation of industry practitioners and academic researchers. The book contains theoretical explanations about the various elements forming a communication system, practical hands-on examples and lessons that help synthesize these concepts, and a wealth of important facts and details to take into consideration when building a real-world communication system.

The companion site for the book which contains links to complimentary online lectures, slides, and example MATLAB code can be found at https://sdrforengineers.github.io. MATLAB is a very powerful programming language and toolset used by scientists and engineers. MATLAB is not a cheap tool, but there is a home user licence available for a more reasonable price. To do some of the exercises in the book you'll probably at least require the core MATLAB plus the Communications System Toolkit which is an extra add on.

The full book can be purchased as a Hardcover from Amazon, or downloaded freely online as a PDF.

If you're interested in a similar book, there is also the free DesktopSDR book which uses RTL-SDR dongles for the practical examples.

SDR For Engineers Book
SDR For Engineers Book

Decoding ADS-B in MATLAB Video Tutorial

Over on YouTube the official MATLAB channel has uploaded a new video that is a tutorial on setting up ADS-B decoding in MATLAB. MATLAB is a technical computing language that is frequently used by many scientists and engineers around the world. They write:

Use the software-defined radio capabilities that are part of Communications System Toolbox™ to capture and decode ADS-B messages. ADS-B is a relatively simple standard used by commercial aircraft to transmit flight data such as aircraft ID, position, velocity, and altitude to air traffic control centers. ADS-B messages are 56 or 112 bits long, the data rate is 1 Mbit/sec, and the messages are amplitude modulated signals, transmitted at a carrier frequency of 1090 MHz

The video goes over what ADS-B is, how to receive it, and then goes on to explain a bit of the MATLAB code. This is a good introduction for people wanting to use an RTL-SDR in MATLAB, or for anyone wanting to learn about ADS-B.

Real-time Airplane Tracking with ADS-B Signals and RTL-SDR Radios

An AIS Decoder for MATLAB and the RTL-SDR

RTL-SDR.com reader Mike wrote in to us today to let us know that he has released his AIS decoder for MATLAB and the RTL-SDR. MATLAB is a technical computing language used by many scientists and engineers in the world. Mike writes the following about his work:

Automatic Identification System (AIS) is a communication standard that is used by commercial and recreational maritime vessels to report a ship’s ID, position, course and other information. This data is used for collision avoidance, search and rescue and many other applications. AIS has the following characteristics:

  • Access protocol: Self-organizing Time Division Multiple Access (SOTDMA)
  • Transmission frequencies: 161.975 MHz and 162.025 MHz
  • Transmit Power: 2 W or 12.5 W
  • Modulation: Gaussian Minimum Shift Keying (GMSK)
  • Data Rate: 9600 bits per second

An AIS decoder that uses the RTL-SDR and MATLAB to capture AIS transmissions is posted on MATLAB Central, the MathWorks file sharing exchange. The decoder has three main components

  1. Software to connect MATLAB to the RTL-SDR and bring IQ data directly into the MATLAB workspace (http://www.mathworks.com/hardware-support/rtl-sdr.html)
  2. Demodulation and decoding algorithms to convert the IQ samples into bits and decode the AIS data (http://www.mathworks.com/products/communications/)
  3. A user interface to configure the RTL-SDR, launch the capture and decoding process, and display the decoded messages (http://www.mathworks.com/matlabcentral/fileexchange/57600-ais-decoder)

The MATLAB Central post includes MATLAB source code for the AIS decoder, captured data files from Boston and San Francisco, an app for easy configuration and operation of the decoder, and instructions for installing the RTL-SDR Hardware Support Package and AIS Decoder app.

If you want to learn how AIS works, and how to write a decoder, then a MATLAB example like this is an excellent resource.

DesktopSDR MATLAB RTL-SDR Text Book Released

Back in August we posted about an RTL-SDR related text book called DesktopSDR that was due to be released later in the month. The text book discusses technical SDR topics, with the RTL-SDR used as the radio receiver and MATLAB used as the digital signal processing tool. It looks to be very useful to students of radio or communications engineering. There were a few delays with the release, but it is now out at www.desktopsdr.com. The eBook version is free whilst the print version is soon to be released on Amazon for about $68 USD for the paperback and $89 USD for the hard back

To go along with the book they have also released several accompanying videos that are available at desktopsdr.com/videos.

The books blurb reads:

The availability of the RTL-SDR device for less than $20 brings software defined radio (SDR) to the home and work desktops of EE students, professional engineers and the maker community. The RTL-SDR can be used to acquire and sample RF (radio frequency) signals transmitted in the frequency range 25MHz to 1.75GHz, and the MATLAB and Simulink environment can be used to develop receivers using first principles DSP (digital signal processing) algorithms. Signals that the RTL-SDR hardware can receive include: FM radio, UHF band signals, ISM signals, GSM, 3G and LTE mobile radio, GPS and satellite signals, and any that the reader can (legally) transmit of course! In this book we introduce readers to SDR methods by viewing and analysing downconverted RF signals in the time and frequency domains, and then provide extensive DSP enabled SDR design exercises which the reader can learn from. The hands-on SDR design examples begin with simple AM and FM receivers, and move on to the more challenging aspects of PHY layer DSP, where receive filter chains, real-time channelisers, and advanced concepts such as carrier synchronisers, digital PLL designs and QPSK timing and phase synchronisers are implemented. In the book we will also show how the RTL-SDR can be used with SDR transmitters to develop complete communication systems, capable of transmitting payloads such as simple text strings, images and audio across the lab desktop.

Download the book at desktopsdr.com
Download the book at desktopsdr.com

DesktopSDR: A new free textbook about using the RTL-SDR with MATLAB

On the 26th of August a new technical text book titled “Software Defined Radio using MATLAB® & Simulink® and the RTL-SDR” is due to be released for free in eBook form and in print form for an as of yet unknown price on Amazon. The book is written by four members of the Department of Electronic and Electrical Engineering at the University of Strathclyde in Scotland. 

MATLAB is a technical computing language and software suite used commonly by professional and student scientists and engineers. It is similar to GNU Radio in terms of its digital signal processing (DSP) capabilities. Back in January 2014 the MATLAB team released an update which enabled the RTL-SDR to be used as an RF input device.

The text book’s blurb reads:

The availability of the RTL-SDR device for less than $20 brings software defined radio (SDR) to the home and work desktops of EE students, professional engineers and the maker community. The RTL-SDR can be used to acquire and sample RF (radio frequency) signals transmitted in the frequency range 25MHz to 1.75GHz, and the MATLAB and Simulink environment can be used to develop receivers using first principles DSP (digital signal processing) algorithms. Signals that the RTL-SDR hardware can receive include: FM radio, UHF band signals, ISM signals, GSM, 3G and LTE mobile radio, GPS and satellite signals, and any that the reader can (legally) transmit of course! In this book we introduce readers to SDR methods by viewing and analysing downconverted RF signals in the time and frequency domains, and then provide extensive DSP enabled SDR design exercises which the reader can learn from. The hands-on SDR design examples begin with simple AM and FM receivers, and move on to the more challenging aspects of PHY layer DSP, where receive fi lter chains, real-time channelisers, and advanced concepts such as carrier synchronisers, digital PLL designs and QPSK timing and phase synchronisers are implemented. In the book we will also show how the RTL-SDR can be used with SDR transmitters to develop complete communication systems, capable of transmitting payloads such as simple text strings, images and audio across the lab desktop.

While the book is not yet released the full table of contents is currently available for viewing on their downloads page. From looking at the table of contents, we can see that the text book looks very comprehensive and will likely be extremely useful for students who are learning RF and DSP concepts in university level classes. The team behind the book (desktopsdr.com) also have a YouTube channel where it appears that they are releasing supporting videos.

We will post again when the book is released.

Download the book at desktopsdr.com
Download the book at desktopsdr.com

https://www.youtube.com/watch?v=kK7xNQ9NVno

Visualizing ADS-B Data in 3D using MATLAB

Over on Reddit user JorgeGT has posted an animated 3D visualization of his local ADS-B air traffic data using a MATLAB script he wrote. The script collects data from a dump1090 server. If you have a copy of MATLAB, his code can be downloaded from Github here. To run the code JorgeGT writes that you’ll need to do the following.

  • Get dump1090 running on an accessible server: http://url:8080.
  • Get countries/states/provinces SHPs from Natural Earth if you want them to show them and store them in a folder called 10m_cultural.
  • Have a look at my MATLAB script and try to run it.
MATLAB Visualization of ADS-B Data
MATLAB Visualization of ADS-B Air Traffic Data

Studying VOR Signals with the RTL-SDR

VHF Omni Directional Radio Range (VOR) signals are used in aviation as a short range radio navigational system. Amateur radio hobbyist F4GKR decided to study these VOR signals by recording them using his RTL-SDR, and then analyzing them in MATLAB. On his post he shows his method of analysis and discusses his results.

VOR Spectrum and Waterfall
VOR Spectrum and Waterfall

RTL-SDR Now Supported by MATLAB

The Communications System Toolbox in MATLAB 2013b now supports the RTL-SDR dongle. MATLAB is a scientific computing software product which scientists and engineers use for complex technical computations and simulations.

The RTL-SDR radio support package enables you to design wireless receivers using real world signals. Using Communications System Toolbox™ in conjunction with an RTL-SDR USB radio, you can design and prototype systems that process real-time wireless signals in MATLAB® and Simulink®.

Wireless engineers, students, and hobbyists can learn to receive and decode real-world radio signals using this low cost RTL-SDR hardware connected to your computer.

Key Features:

  • RTL-SDR radio as an I/O peripheral to receive streaming RF signals
  • Configurable center frequency and sample rate
  • NooElec™ NESDR Mini USB Stick (R820T) and NooElec NESDR Nano USB Stick (R820T) SDR devices with frequency range 30MHz – 1.8GHz
  • Compatible with other RTL-SDR USB radios (eg., Terratec T-Stick E4000)
  • Several application examples for getting started:
    • FM Mono / Stereo with RTL-SDR
    • FRS Receiver with RTL-SDR
    • Spectral Analysis with RTL-SDR radio
    • Frequency offset calibration with RTL-SDR