Begun with a frustration on the lack of technical public information on ADS-B and Mode-S in the year 2015, I created a live online document to record my understanding of ADS-B data. Previously, this was known as "ADS-B Decoding Guide" project. Together with the tutorial, we also developed its related Python library, the pyModeS. With time, I received many feedbacks, compliments, and contributions from open-source community users.

Since the beginning of 2017, the interests of tapping into Enhanced Mode-S (EHS) data brought us a whole new chapter of Mode-S inference and decoding into the pyModeS. This also enriches the "ADS-B" guide. With the advance in this area, I am planning to compile a more comprehensive online book to cover both ADS-B and Mode-S decoding and related topic.

That's the starting of this new repository. I am also starting to host the online book on my own server to allow more flexibility of editing and publishing. You can read the most up-to-date book on mode-s.org.

Oh, it is still GNU GPL. It was great to see the pull requests from different contributors previously. I am looking forward to seeing more comments and pulls from the community. Enjoy!