There are a lot of open source projects. And technology (algorithms and receivers) wise it isn't too complicated nor a secret. That stuff is almost 100 years old.

An easy start is always looking at VHF reflection of strong transmitters that are not creating a lot of noise (like FM stations). ILS or VORs stations are classics.

There are also a lot of meteor and space radars ( https://en.wikipedia.org/wiki/GRAVES_(system) ). Universities are super happy in publishing very very detailed (https://www.iap-kborn.de/en/research/department-radar-remote...) specs of their sky radars. And frequencies are well known for ages.

The quality usually depends on the vendor adapting it to their silicon.

If you look at ST and their STM32 the lwip integration is extremely bug ridden. Just read all the articles in their forum from "Piranha". I also struggled with extremely hard to debug bugs coming from their adaption layers.

Lwip itself has a solid quality.

That sounds like ST. They make some really intriguing chips at good prices, but the tradeoff is that their hardware and software are full of bugs.

Can you say, with which hardware does, the LWIP stack, work well?

There are high quality alternatives:

- NetXDuo from ThreadX. It's Opensource for a while now.

- Zephyr also brings its own stack

It'd be interesting to see a breakdown of IP stacks for MCUs, their performance, how many security issues, etc.

NetX, Zephyr, LwIP, and SmolTCP all sort of fit in this realm these days it seems like. Probably others too... but yeah hard to discern the differences at a high level without digging in.