How to noticeably speed up calculations?

Question

Radio communication

Dear colleagues, I ask for your advice.
The task, in principle, is understandable and can be solved: it is necessary to calculate the uncertainty function (uncertainty body, mismatch function) of the radar signal. The whole problem is that the signal itself is approximately 20.48 million samples and this is not the limit.
Such a number of readings leads to operating with arrays whose dimensions are ~ 21x21x10 million.
It is assumed that once all the values ​​of the FN have been calculated and saved, in the future, if necessary, it will be possible to investigate the necessary subdomains. Actually, the algorithms for generating a signal and calculating the FN are maximally vectorized, it remains to understand how to correctly calculate everything in a reasonable time.
I looked at possible solutions, settled on using the GPU, but still, it will take time, which I do not have.
Probably, those who process images or someone else have already encountered such problems and solved them. Please share.

Answer 1

Buy time from a supercomputer