基于精密时间基准测试仪的高精度信号源的设计

摘要

精密时间基准测试仪需要高精度标准频率信号。针对传统晶体振荡器产生信号精度低、频率固定、长期稳定性差的问题，设计了基于FP GA的高精度信号源系统。系统采用小型铷原子钟P RS10产生参考信号，结合FP GA与上位机，设计了输出20 kHz~40 MHz的频率、波形可实时程控高精度信号源。测试5 MHz和10 MHz正弦信号，精度可达10-9量级，杂散在-64.4 dBm以下，满足高精度标准频率信号的要求。%Precision time benchmark need high-precision standard-frequency signal. A high-precision signal source system design was put forward which was based on FPGA to solve problems that the signal produced by traditional crystal oscillator was low-precision,frequency-fixed,single waveform and long-term stability is poor.The system used a miniature rubidium atomic clock PRS10 to generate reference signal combing with FPGA and PC,20 kHz to 40 MHz high-precision signal source whose waveform and frequency can be real-time changed.The results of tests about 5 MHz and 10 MHz sinusoidal signal show that precision can be up to 10-9 order of magnitude and the spurious is under-64.4 dBm,meeting the requirements of high-precision standard-frequen-cy signal.