Design and implementation of low phase noise 100MHz TCXO based on phase locked method

The rapid development of electronic technology calls for high frequency, low phase noise and high stability of temperature compensated crystal oscillator (TCXO). This paper describes the design and implementation of high-frequency TCXO based on phase-locked method for solving the current TCXO industry pain points such as phase noise, compensation accuracy and mass production. Firstly, this paper establishes the theoretical noise model of phase locked loop. Then, by using phase locked loop to lock a low phase noise voltage controlled crystal oscillator (VCXO) to reference input signal which is generated by a 10MHz TCXO, a low phase noise 100MHz TCXO have been designed and realized. The frequency shift is ±0.28ppm(@-40°C~+85°C); and the phase noise is ≤ -117dBc/Hz@100Hz, ≤ -153dBc/Hz@lkHz, ≤ -171dBc/Hz@10kHz, ≤ -176dBc/Hz@100kHz respectively. Experimental results show that the low phase noise 100MHz TCXO implemented in this way has good frequency-temperature characteristics, excellent phase noise performance, and easy mass production as well.