This MIT Technology Review report provides the details of the work done by
Professor Humphrey and his team to reverse engineer starlink signals:
https://www.google.com/amp/s/www.technologyreview.com/2022/10/21/1062001/spacex-starlink-signals-reverse-engineered-gps/amp/

It is worth it to mention that Elon Musk does not like using starlink for
navigation which is the motivation behind Humphrey

Although the report mentions Humphrey non-peer reviewed paper, actually the
peer-reviewed paper has been published here

https://ieeexplore.ieee.org/abstract/document/10107477?casa_token=ws8yh0wRnRsAAAAA:Q0LZ3Gt-vxKsGQ170OhIp4X4tQoa_U2m6DlBKY7a-A0EYxTzRd4VLzpHkZKSglEPiMEJKK4XTHk