1MHz phase noise point for Phase Lock Loop

[Analog.World]

Why most journal and book authors quote 1MHz phase noise data ?
What is the physical significance behind it ? Something to do with specification from communication related application ?

 

[dick_freebird]

Phase noise has a slope with frequency and often you are
interested in either the PN which violates an adjacent
channel, or one that violates the channel receiver's
data constellation phase "bins". But it could be also as
simple as man's fondness for nice round numbers when
creating test methods.