For anyone who hasn't read it, I highly recommend
R. V. Jones' book, "The
Wizard War" - it covers all the various navigation systems (on both sides),
and much more.
This is very good book, but it is getting a bit outdated - at least
the old edition I read many years ago (has it been updated? I do not
know.). In the past 15 or so years, quite a lot of information about
German technology has come out* that takes a bit of the shine off
Allied developments.
* and not from the Space Nazi nut jobs, either. They can be ignored.
--
Will