Research On The Method Of Compressing The Linewidth Of The Crystal Resonator Based On Boder Effect

Conventional oven controlled crystal oscillator has disadvantages of low precision, low stability, easy to aging and other aspects. Based on the analysis of common OCXO, this paper proposes a method of compressing the bandwidth of crystal resonator with the theoretical basis of the edge effect of fuzzy region, which solves the above problems effectively. In the view of high-resolution, the crystal resonant frequency is not a single point, but a range of interval. The purpose of this approach is that compressing this interval, in order to improve the accuracy of the crystal oscillator frequency. LC resonator is used in common crystal oscillators, but in this paper the crystal oscillator contains two crystals, one for frequency selection, and another for frequency stabilization. When the crystal is oscillating, by adjusting the center frequency of the crystal for frequency selection makes frequencies of these two crystal resonators being close. So that edges of bandwidths of these two crystal resonators overlap, eventually the oscillation circuit works in this region, with compressed oscillations range and improved accuracy. This paper includes oscillation circuit, temperature control circuit, and the method of measuring the output signal of the oscillation circuit. Ultimately through the experiment of measuring the phase noise of the oscillator, it is find that the phase noise is reduced and the accuracy of the circuit is improved. So making use of the edge effect can realize the compression of the resonant crystal bandwidth.