Frequency estimation of microwave signals is a crucial functionality for applications ranging from biomedical engineering to electronic warfare systems. Photonics-based frequency measurement systems offer advantages of flexible reconfigurability and wide bandwidth compard to electronic methods. However, photonic based systems are limited by trade-offs between measurement range and accuracy. Here, we propose and experimentally demonstrate a frequency identification system with ultrahigh accuracy of 900 kHz, large bandwidth of 39 GHz, and the capability of multiple frequencies estimation. The great performance is achieved by wideband distributed frequency-to-power mapping created by self-heterodyne low-coherence interferometry. The results show that the system we proposed is beneficial for applications in RF spectrum sensing of modern communication and radar applications.

中文翻译：

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基于自外差低相干干涉技术的宽带多微波频率精确识别

微波信号的频率估计对于从生物医学工程到电子战系统的各种应用来说都是至关重要的功能。与电子方法相比，基于光子学的频率测量系统具有灵活的可重新配置性和宽带宽的优势。但是，基于光子的系统受到测量范围和精度之间折衷的限制。在此，我们提出并通过实验演示了一种频率识别系统，该系统具有900 kHz的超高精度，39 GHz的大带宽以及多种频率估计的能力。自外差低相干干涉测量法创建的宽带分布式频率至功率映射可实现出色的性能。