This calculator converts the ratio of Frequency variation to Center frequency (Hz/kHz/MHz/GHz) to parts per million (PPM)
ppm = (df/F)*106
- F is the center frequency
- df is the peak frequency variation
- ppm is the resulting parts per million
At a frequency of 1 GHz if the system is specified for a peak frequency shift of 100 Hz, then the reference oscillator has to be better than +/- 0.1 ppm.