How to combine (range, elevation, azimuth) data to obtain a meaningful joint probability density function

I have available (range, elevation, azimuth) data acquired by a radar sys. I'd like to know if it could be meaningful to consider their joint probability density function and if yes how do I have to combine them in order to do this right?

Do you have any idea about this? I'd appreciate any suggestion since I need help to connect my knowledge concerning joint probability distribution between to generic variable X1,X2 with the real world( that in this case is represented by (range, elevation, azimuth) data)

Thank you in advance!