Allan variances calculation and simulation

The article deals with the oscillator frequency stability solution. Phase noise is modeled and simulated in the frequency domain and consequently recalculated to the time domain for the Allan variance expression. Given phase noise points are linearly interpolated, randomized and transferred to the time domain, where the time fluctuations are calculated. These are used to obtain simple and overlapping Allan variances in a dependency on the averaging time. Simultaneously, the integral formula for the direct conversion from the frequency to the time domain is used to get results for comparison. Results show the possibilities of the presented procedure that is going to be used for the evaluation of direct time domain oscillator frequency stability measurements. Processes are focused on the area of space communications where a question of the oscillator frequency stability is very important.