How to test an RF crystal oscillator performance integrated into a Cellular radio?
Assuming you have audio spectrum analysis capability, get hold of a decent RF mixer, mix two identical oscillators, and analyse the (low side) result. This is easiest if you can pull one of the oscillators 1kHz or so,(e.g. by tuning the loading capacitances).

The noise, jitter, etc you see will be the sum of two nominally identical uncorrelated sources, so subtract 3dB to get the level from each source.