Summer of Math Exposition

A few points of feedback:

• As a framing thing, it’s unclear to me what encoding a signal onto light means — it would have been helpful to have that elaborated upon. I have more a pure math background than anything else, so maybe it’s an audience issue, but generally I found it somewhat tricky to comprehend the connections to the world, and would have preferred some elaboration.
• Having more visuals — like including the graph of your root-raised cosine — would be nice.
• With regard to prose, you can usually delete lines like “I want to add a few closing thoughts” from the start of a conclusion — the big conclusion header announces this!

This post felt like a speedrun from basic signal theory to modern modulation schemes, which comes with ups and downs.

For someone with a vague understanding of the concepts involved, this was a nice roadmap of how one might mathematically arrive at the idea of OFDM, and it definitely inspired me to play around with it a bit myself.

However, due to the sheer amount of information in a relatively short post, it also feels a bit rushed. Most of the concepts are introduced at a level of “this can be done. here’s some formulas. trust me.”. I feel like a more indepth explanation of key steps would have been more engaging. Some other concepts are taken for granted, even tho they are likely far from trivial for somebody unfamiliar with the topic.

Motivation - Clear motivation from the beginning, the author has a lot of knowledge on this topic and wants to share this knowledge with anyone wondering about how wireless communications work. The introduction starts strong by introducing this curiosity about the world of communication around us before diving into the technical details.

Clarity - the writing and explanations are geared towards someone with a good understanding of the math, but several additional resources are also provided for those to review the information or go deeper. The post goes into detailed explanations of equations and the motivation for specific terms/coefficients without simply listing the equations or using too much jargon - I think this is nicely presented for a technical audience.

Novelty - The motivation and author’s familiarity and curiosity about the topic make the reading enjoyable and provided a good introduction on the topic.

Memorability - The interactive feature helped me understand how a shorter period can lead to interference - that was nicely presented, I wish there were more features like this in the article!

Could have used more visualisations — especially early on — but overall very well written!