※ 引述《normanT (門中有心)》之銘言： : 因為非電機本科 所以在看論文的時候有些符號不知道是什麼東西 : 所以想再這邊請問一下 S11 (11是S的下標)是什麼意思？ : 在這邊給一下前後文 : This section considers a simple interconnect example for : which the generation of a macromodel fails. We present the example : under the standpoint of the design engineer, who knows : the physical geometry of the interconnect and is required to : generate a SPICE-compatible model in order to carry out the : design. The structure is a three-conductor transmission line. Its : scattering matrix is first computed over a bandwidth of 4 GHz : using a commercial frequency-domain 3-D field solver. Then, : the various scattering matrix entries are processed by the very : popular and robust vector fitting (VF) algorithm [3] in order to : produce a lumped model for the structure. It is well known that : VF produces a model in poles-residues form, which is readily : synthesized into a SPICE netlist. It turns out that VF fails to : provide a reasonably accurate model. As an example, we report : in Fig. 1 the original return loss S11 and the corresponding : response of a rational model with 20 poles. Although the raw : data are quite smooth, the model is very inaccurate. 簡單的說，你想找到S11是什麼 就去找 two port network（去wiki找最快） 跟two port有關的東西有 S(11,12,21,22) Y(11,12,21,22) Z(11,12,21,22) ...... 而two port是電子電機很重要的觀念 （雖然現在的電路學跟電子學課程都不太教了） 在研究noise時會常常用到，在做RF、MMIC更是天天會碰到這些 其他相關的還可以找找state space Smith Chart Noise Figure -- 為什麼那邊那個人那麼傷心呢? ││││││ 因為他是北部人啊，吃的比我們還毒哩! 2.5ppm ˍ︵ │││ 還好我們 0.5ppm ◥ ◥ 2ppm ╱ ╱▏ ││ 不用吃… ◤ ◥ ◤ ◥ │￣▏ ˍ 0ppm | | | ╱ ╱ ﹨ ◥◢ ￣ （||） ω ╯ ㄦ --

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