WWVB is a very interesting radio station. It has high transmitter power (50,000 watts), a very efficient antenna and an extremely low frequency (60,000 Hz). For comparison, a typical AM radio station broadcasts at a frequency of 1,000,000 Hz. The combination of high power and low frequency gives the radio waves from WWVB a lot of bounce,
and this single station can therefore cover all of the continental United States plus much of Canada and Central America as well …The coverage map looks like this:
So this single transmitter can be received well into the Pacific and Atlantic oceans as well as parts of Canada, Central America and even part of South America.
It would seem to me that it would only take maybe a dozen or so of such transmitters to cover the entire
plant.
In fact, WWV can indeed cover the globe when propagation is good enough. Just like a GPS satellite, it constantly broadcasts the time, and it seems possible that one could use its signals in precisely the same way as one uses GPS to determine one's location, given several signals. There is a rub, though - WWV broadcasts in the high frequency part of the radio spectrum (1.8-30 MHZ is HF) which is subject to ever changing and anomalous propagation.
GPS operates in the gigahertz range, which is not subject to this kind of anomalous propagation. It is more or less strictly line of sight, perhaps bouncing off raindrops and snowflakes by by and large going in a straight line, unlike HF signals which bend when the encounter the ionosphere (or the giant crystalline orb inside the hollow earth in which we live which contains all of "space").