Microwave/millimeter-wave photonics is playing a prominent role in overcoming the challenges of RF signal generation and processing. This evolving technology has many advantages, such as RF carrier stability and broad operating bandwidth, and is applicable to a wide range of civil and military applications such as 5G communication networks, radar/jammer systems, and medical imaging. In this work, we leverage the multidimensional capabilities of microwave photonics in order to generate multi-band/multi-mode radar signals for multi-purpose applications. Our proposed system can generate up to five radar bands, simultaneously, with different modulation bandwidths, without hardware modifications. Additionally, various radar waveforms can be transmitted, simultaneously, over the corresponding radar bands. The RF radar signals are generated optically using a reconfigurable frequency comb source, which reduces the system cost significantly. The stability of the RF carriers is experimentally tested and compared with that of the mode-locked-loop-based laser sources, wherein a comparable performance is observed. Experimental results show the generation of four radar waveforms, including frequency modulated waveforms (pulsed linear frequency modulation and frequency modulated continuous wave) and polyphase codes (Barker-11 and Barker-13). Moreover, five carrier frequencies are used to transmit the various radar modulation schemes. These are 5.25, 9.325, 16.1, 26.4, and 28.15 GHz RF carriers. The signal quality is measured experimentally, and high signal-to-noise ratio (SNR) of 35, 30, 30, 25, and 20 dB SNR was observed in the C-, X-, Ku-, K-, and Ka-bands, respectively.

中文翻译：

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基于光子学的多波段/多模式雷达信号生成

微波/毫米波光子学在克服RF信号生成和处理的挑战中扮演着重要角色。这项不断发展的技术具有许多优势，例如RF载波稳定性和广泛的工作带宽，并且适用于广泛的民用和军事应用，例如5G通信网络，雷达/干扰系统和医学成像。在这项工作中，我们利用微波光子学的多维功能来生成用于多用途应用的多波段/多模式雷达信号。我们提出的系统可以同时产生多达五个雷达频带，具有不同的调制带宽，而无需进行硬件修改。另外，可以在相应的雷达频段上同时发送各种雷达波形。使用可重新配置的频率梳源以光学方式生成RF雷达信号，从而显着降低了系统成本。通过实验测试了RF载波的稳定性，并将其与基于锁模环路的激光源的稳定性进行了比较，其中观察到了相当的性能。实验结果表明生成了四个雷达波形，包括调频波形（脉冲线性调频和调频连续波）和多相代码（Barker-11和Barker-13）。此外，五个载波频率用于传输各种雷达调制方案。它们是5.25、9.325、16.1、26.4和28.15 GHz RF载波。信号质量是通过实验测量的，在C-，X-，Ku-，K-，