※ 引述《normanT (门中有心)》之铭言： : 因为非电机本科 所以在看论文的时候有些符号不知道是什麽东西 : 所以想再这边请问一下 S11 (11是S的下标)是什麽意思？ : 在这边给一下前後文 : 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. 简单的说，你想找到S11是什麽 就去找 two port network（去wiki找最快） 跟two port有关的东西有 S(11,12,21,22) Y(11,12,21,22) Z(11,12,21,22) ...... 而two port是电子电机很重要的观念 （虽然现在的电路学跟电子学课程都不太教了） 在研究noise时会常常用到，在做RF、MMIC更是天天会碰到这些 其他相关的还可以找找state space Smith Chart Noise Figure -- 为什麽那边那个人那麽伤心呢? ││││││ 因为他是北部人啊，吃的比我们还毒哩! 2.5ppm ˍ︵ │││ 还好我们 0.5ppm ◥ ◥ 2ppm ╱ ╱▏ ││ 不用吃… ◤ ◥ ◤ ◥ │￣▏ ˍ 0ppm | | | ╱ ╱ ﹨ ◥◢ ￣ （||） ω ╯ ㄦ --

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