标题： 交叉谱实验方法 显示英文标题

标题： The cross-spectrum experimental method

摘要： 被测设备（DUT）的噪声同时由两个仪器进行测量，每个仪器都贡献其自身的背景噪声。 平均交叉功率谱密度趋于DUT的功率谱密度。 即使DUT的噪声显著低于背景噪声，该方法也能提取出DUT的噪声谱。 在对实际实验进行快照后，我们探讨了统计理论和估计器的选择。 描述了一些实验技术，并参考了射频/微波系统和光子系统中的相位噪声和幅度噪声。 该方法的应用范围很广。 最后一节简要介绍了射电天文学、辐射计、量子光学、测温（基础和应用）、半导体技术、冶金学等。 本报告旨在作为教程，而非高级研究的报告，但面向广泛的读者群体：技术人员、实践者、博士生、学者和全职科学家。 显示英文摘要

摘要： The noise of a device under test (DUT) is measured simultaneously with two instruments, each of which contributes its own background. The average cross power spectral density converges to the DUT power spectral density. This method enables the extraction of the DUT noise spectrum, even if it is significantly lower than the background. After a snapshot on practical experiments, we go through the statistical theory and the choice of the estimator. A few experimental techniques are described, with reference to phase noise and amplitude noise in RF/microwave systems and in photonic systems. The set of applications of this method is wide. The final section gives a short panorama on radioastronomy, radiometry, quantum optics, thermometry (fundamental and applied), semiconductor technology, metallurgy, etc. This report is intended as a tutorial, as opposed to a report on advanced research, yet addressed to a broad readership: technicians, practitioners, Ph.D. students, academics, and full-time scientists.