For military use, where you are trying to blend in with civilian equipment, either the direct sampling clock, or the local oscillator frequency, could be random

For military use, where you are trying to blend in with civilian equipment, either the direct sampling clock, or the local oscillator frequency, could be randomly chosen in quite a wide range at bootup and still have the device work. In todays world with everything software reconfigurable, changing the sampling rate or local oscillator frequency is very do-able.