The singular spectrum analysis (SSA) technique has been applied for the elimination of ripples in the measured phase constant ($\beta$) of transmission lines with small impedance mismatches by the line–line method. Compared with other postprocessing switching error (SW) procedure, the error correction (EC) technique, and the rolling average (RA) approach, it has been found that the SSA technique is more effective in removing the ripples of measured $\beta$ of reflecting and nonreflecting X-band and/or Ku-band waveguide straights with different lengths. As a metric for quantitative analysis, we computed the normalized root-mean-square-error (RMSE) and goodness-of-fit (GoF) values of the retrieved $\beta$ values. Better performances of the SSA technique over the SW procedure, the EC technique, and the RA approach are observed when the RMSE and GoF values are considered. Besides, the effect of artificial noise added to scattering parameters on the overall performance of the SSA technique in $\beta$ determination of symmetric reflecting and nonreflecting lines was examined. Furthermore, we investigated the roles of the window length and the number of principal components in the application of the SSA technique and then proposed a two-step procedure for $\beta$ extraction of dispersive lines considering their roles.

中文翻译：

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奇异谱分析技术在对称反射线和非反射线相位常数确定中的应用

奇异谱分析 (SSA) 技术已用于消除测量相位常数中的纹波 ($\beta$) 具有小阻抗失配的线-线方法的传输线。与其他后处理切换误差 (SW) 程序、误差校正 (EC) 技术和滚动平均 (RA) 方法相比，已经发现 SSA 技术在去除测量的纹波方面更有效。$\beta$ 反射和非反射 X-带和/或 库带不同长度的波导直线。作为定量分析的指标，我们计算了检索到的归一化均方根误差 (RMSE) 和拟合优度 (GoF) 值$\beta$值。当考虑 RMSE 和 GoF 值时，观察到 SSA 技术优于 SW 程序、EC 技术和 RA 方法的性能。此外，添加到散射参数中的人工噪声对 SSA 技术的整体性能的影响$\beta$检查了对称反射线和非反射线的确定。此外，我们研究了窗口长度和主成分数量在 SSA 技术应用中的作用，然后提出了一个两步程序$\beta$ 考虑到它们的作用来提取色散线。