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Introduced GPS, short-wave radio timing technology. Based on analysis of high stability constant temperature crystal and its frequency characteristics, design a high precision clock system based on GPS, short-wave radio-technology timing design. The system using GPS, short-wave receiving and processing module to get the second pulse signal, the time information, after signal check, delay correction, pulse select, pulse statistics , pulse filter and kalman arithmetic process, PWM voltage adjust, then get a standard second pulse signal, realize calibration of the crystal oscillator frequency, and obtain a short-term and long-term frequency stability are excellent time and frequency, at the same time using 1pps signal which is from constant temperature crystal to calibrate the time chip, after frequency correction, output a high precision time. Described the basic working principle and some module circuit, the experimental results show that, at the time of not more than 1 hour, frequency accuracy up to 0.9×10-9 , due to the method is practical and easy , this system will reach the aim of get higher index point of crystal oscillator calibrated. 