Vijay,
A great example for measuring RF phase noise can be found in the LabVIEW Example Finder. The name of the VI is "MT RFSA Phase Noise.vi" This example performs phase noise density measurements on I-Q data acquired using RFSA. You may also want to take a look at Performing Modulation Measurements on Real-World IQ Data With Carrier Frequency Drift to see if phase measurement could be implemented: http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=EEAFD63A09CD3B79E0340003BA7CCD71&p_node=200054&p_source=External
What type of RF signal would you be analyzing? Are you trying to measure phase shift of a carrier frequency that is varying with time?
Shea C
Applications
NI
