Stable scalable digital frequency reference

A system for implementing a scalable stable digital frequency reference, the system comprising:

• a plurality of independent crystal oscillator circuitry coupled to each other, each of the plurality of independent crystal oscillator circuitry comprising:
• (a) an independent crystal oscillator;
• (b) a direct digital synthesizer having a first input from the independent crystal oscillator and second input comprising a phase increment clock source cycle to align all direct digital synthesizers in frequency;
• (c) a phase sampler for sampling an output phase of each direct digital synthesizer into a common synchronous clock domain;
• (d) a sin/cos look-up table stored in a computer-readable medium, wherein the sin/cos look-up table generates a precision digital complex tone based on output of the phase sampler;
• a collective coherent vector sum module for combining the precision digital complex tone in-phase to other precision digital complex tone for each of the other direct digital synthesizer to generate a collective coherent vector sum;
• a phase management block wherein each of the plurality of independent crystal oscillator circuitry compares its own sin/cos vector with the collective coherent vector sum to determine requisite phase and frequency corrections of its own direct digital synthesizer;
• and
• a conditioner for conditioning the collective coherent vector sum and outputting the scalable stable digital frequency reference.