alt Hacker NewsDecca navigation gear was common in British boats operating in near coastal waters right up to the 70s and 80s. The fundamentals of how this system worked were not radically different to the beam systems used for navigation in the war.
https://en.wikipedia.org/wiki/Decca_Navigator_System
Loran and then GPS competed and replaced.
Robert Buderi's book on Radar is an amazing read to one side of this, it drives all the way through to VLSI. Fascinating stuff.
https://books.google.com.au/books/about/The_Invention_that_C...
I had some exposure to Decca, we mainly got by with early Loran (less accurate than Decca), then transitioned to Loran-C (better accuracy) in parallel with reverse engineered NavStar, then onto early civilian GPS with home grown base stations and post processing .. and some time ground truthing older maps to the newer WGS ellipsoid standards.