If you search "pips network" on these forums you will see they have been discussed here off and on for 10 years or so.
The transmission consists of a dit or dash and a pause some multiple of that dit or dash. In the case of this transmission it is a 40 millisecond long dit, with a 4.000 second long pause (many different combinations of pulse length and pause have been seen). The signal starts at some low frequency, makes a pulse, steps up to the next higher frequency, makes another pulse, etc, to the highest frequency, after which it starts over at the low frequency. So you see it allows, in this specific case, for up to 100 different frequencies to be in each sequence.
Based on past receptions, this network appears to be sourced in the US, from 2 different locations. Some frequencies are shared between both networks / locations, and so those frequencies show double dits.
I have never been able to confirm the purpose (or exact sources) of this signal, but my supposition is that it is some kind of ionospheric tool.
T!