We propose and demonstrate an agile X-band signal synthesizer with ultralow phase noise based on all-fiberphotonic techniques for radar applications. It shows phase noise of-145 dBc∕Hz(-152 dBc∕Hz) at 10 kHz(100 kHz...We propose and demonstrate an agile X-band signal synthesizer with ultralow phase noise based on all-fiberphotonic techniques for radar applications. It shows phase noise of-145 dBc∕Hz(-152 dBc∕Hz) at 10 kHz(100 kHz) offset frequency for 10 GHz carrier frequency with integrated RMS timing jitter between 7.6 and 9.1 fs(integration bandwidth: 10 Hz–10 MHz) for frequencies from 9 to 11 GHz. Its frequency switching time is evaluated to be 135 ns with a 135 pHz frequency tuning resolution. In addition, the X-band linearfrequency-modulated signal generated by the proposed synthesizer shows a good pulse compression ratio approximating the theoretical value. In addition to the ultrastable X-band signals, the proposed synthesizer can also provide 0–1 GHz ultralow-jitter clocks for analog-to-digital converters(ADC) and digital-to-analog converters(DAC) in radar systems and ultralow-jitter optical pulse trains for photonic ADC in photonic radar systems.The proposed X-band synthesizer shows great performance in phase stability, switching speed, and modulation capability with robustness and potential low cost, which is enabled by an all-fiber-photonics platform and can be a compelling technology suitable for future X-band radars.展开更多
基金National Research Foundation of Korea(NRF)(2012R1A2A2A01005544)China Scholarship Council(CSC)
文摘We propose and demonstrate an agile X-band signal synthesizer with ultralow phase noise based on all-fiberphotonic techniques for radar applications. It shows phase noise of-145 dBc∕Hz(-152 dBc∕Hz) at 10 kHz(100 kHz) offset frequency for 10 GHz carrier frequency with integrated RMS timing jitter between 7.6 and 9.1 fs(integration bandwidth: 10 Hz–10 MHz) for frequencies from 9 to 11 GHz. Its frequency switching time is evaluated to be 135 ns with a 135 pHz frequency tuning resolution. In addition, the X-band linearfrequency-modulated signal generated by the proposed synthesizer shows a good pulse compression ratio approximating the theoretical value. In addition to the ultrastable X-band signals, the proposed synthesizer can also provide 0–1 GHz ultralow-jitter clocks for analog-to-digital converters(ADC) and digital-to-analog converters(DAC) in radar systems and ultralow-jitter optical pulse trains for photonic ADC in photonic radar systems.The proposed X-band synthesizer shows great performance in phase stability, switching speed, and modulation capability with robustness and potential low cost, which is enabled by an all-fiber-photonics platform and can be a compelling technology suitable for future X-band radars.