To understand what this course is about, please first have a look at my book. While the mathematics in the text is simple, I was looking for a way to explain the fundamental concepts of DSP and Software Defined Radio (SDR) without using any mathematics. Consequently, this course is a summary of main ideas in relation to wireless communication systems from an SDR perspective.

## Rapid Skill Acquisition

Emphasizing on the most valuable stuff is crucial to learning any field. This is the key to rapid skill acquisition where we can go from 0.00 to 0.75 in a reasonably quick time. To understand this further, consider the following series.

\begin{equation*}

\frac{1}{2} + \frac{1}{4} + \frac{1}{8} + \frac{1}{16} + \cdots = 1

\end{equation*}

Now let us draw this series in a diagram.

I want to bring your attention to the following points.

- The same concept is much easier to understand from the above diagram as compared to the equation. While a mathematician would rightly argue that this is not a rigorous proof, it serves our purpose well.
- Even though 1/2 + 1/4, the shaded part in the diagram, does not become 1, it covers a substantial part of the whole. Similarly, from watching these videos and doing the provided GNU Radio exercises, you will gain an expert working knowledge of the subject that can be acquired within a reasonable time.

In old days, the information was scarce and we needed to learn everything, regardless of where it was coming from. In the past few decades, particularly with the rise of wireless connectivity and Internet, we have far more information than we can handle and the target should be to save our time and energy by separating the important from the unimportant. This is where I help the viewer by summarizing the main ideas.

## Learning = Information + Activity

You might think that if you can read the book and understand all the concepts, what is the advantage of watching the videos and doing the GNU Radio exercises. Below I describe the main issue with most online courses and how this course solves that problem.

At its core, learning anything involves two parts: (a) information, and (b) activity. A simple act of walking or climbing to the top of any stairs is very difficult by committing only one leg to this task. Similarly, the first step towards expertise is acquiring information through books, people and online resources. The second step is doing the activity. Then, continue the cycle.

Information → activity → more information → more activity, ……

Some experts refer to this as the Input + Output cycle of our minds. In our context, these two parts are: (a) knowledge of communications and DSP algorithms, and (b) building (in fact, coding) the software defined radios.

To complement the knowledge part from the video lectures, this course provides several GNU Radio Companion (GRC) exercises for you to play with and learn about wireless communications by walking the path yourself. An example screenshot of a flowgraph is shown below (click on the image to enlarge it).
For some built-in blocks, I explain the logic behind C++ code and relate them to the DSP algorithms explained in the lecture.

In the light of the above, this course is more suited to the following audiences.

- Telecommunication professionals interested in gaining hands-on knowledge of what exactly goes on in the physical (PHY) layer of a wireless network
- Any radio hobbyists
- General technical persons looking to expand their knowledge outside their areas of specialities

Most importantly, you will become able to visualize the amazing world of signals that lies underneath the seemingly simple process of bits sent and bits received. As an example, see a short demo based on the flowgraph above.

## Course Contents

You can access the course here.

- Introduction to signals + DSP
- Introduction to systems
- Linear modulations
- Phase Locked Loop (PLL)
- Carrier phase synchronization
- Carrier frequency synchronization
- Timing or clock synchronization
- Wireless channel
- Equalization
- Orthogonal Frequency Division Multiplexing (OFDM)

Fantastic read. The author makes it easy to understand the wireless concepts without needing a degree in mathematics and I highly recommend that you take his online course which compliments the book. It’s definitely a book that I will be referring back to again and again.

Alan Lawrence, via email

Basic | Complete |

10-Chapter eBook (PDF, 828 pages) | |

Video Lessons (8+ hours) | Video Lessons (8+ hours) |

Original Slides | Original Slides |

48 GNU Radio Companion (GRC) exercises | 48 GNU Radio Companion (GRC) exercises |

**Frequently Asked Questions**

*Q.** Is it a guide to build an SDR?*

*A**.* Yes and no. The focus of this course is not on SDR hardware but instead on the DSP part. Using concepts from time and frequency domains, you will come to know how to produce IQ samples on the Tx side that are fed into the SDR hardware. On the Rx side, once the RF signal is converted into IQ samples, you will understand the physical layer (PHY) algorithms leading to the detection of bits.

*Q.** Can GNU Radio be installed on Windows as well?*

*A**.* Yes. See this link. Remember that most flowgraphs work with GNU Radio version 3.8 or higher.