大家早上好，这里我有一个关于EM模拟中“细胞数/波长数”选项的问题。我已经阅读了有关EM模拟中Mesh选项的文档。从文档中，随着细胞数量/波长的增加，您可以获得更准确的结果。在这种情况下，我假设忽略模拟的时间，主要目的是模拟的准确性。我用这个选项进行了测试，这对我来说是一个问题。在我的工作中，一个50欧姆TL与RO4003c，导体厚度= 17um，sub。厚度= 0.504 mm，2.45 GHz为1.12mm（这是LAB中的实际尺寸）。根据这些信息，我将RO4003C的er调整为er = 3.62。然后，我通过EM模拟模拟这个物理宽度。 1.case：80个细胞/波长：S11：-40dB 2.case：180 celss /波长：S11：-55dB，两种情况下都是“匹配”，180个细胞/波长给出更好的结果。在这一步，您可以得出结论：80cells /波长就足够了，因为实际上对于非常好的校准，VNA只能得到-65dB的最佳结果（这是我们在LAB中得到的最好结果），所以我们无法区分这些差异。现在，我将这种方法应用到我的实际电路中，即50欧姆耦合器。图1：具有80个单元的耦合器（粗线是80个单元，细线是180个单元）图2：具有180个单元的耦合器如您所见，现在差异非常明显。我们关心耦合分支的匹配条件（S33），耦合（S31）和隔离（S41）。 S31没有变化，但S33和S41变化很大。对于180个细胞，S33是匹配的，但在我看来，80个细胞不匹配。所以，我的问题是，我们应该依赖哪些价值观？如果你需要一些检查我附加了我的工作区最好的问候，Rinc耦合器_80cells.PNG81.0 KBCoupler.7zap3.1 MB 以上来自于谷歌翻译 以下为原文Good morning everyone, here i have a question about "Number of cells/wavelength" option in EM simulation. I already read documents about the Mesh options in EM simulation. From documents, as you increase the number of cells/wavelength more, you get more accurate results. In this case, i assume to neglect the time of simulation, the main aim is the accuracy of simulation. I made a test with this options, here it arises a question for me. In my work, a 50 Ohm TL with RO4003c, conductor thickness = 17um, sub. thickness = 0.504 mm, at 2.45 GHz is 1.12mm ( this is a real dimension in LAB). From this information, i adjust the er of RO4003C as er=3.62. Then, i simulate this physical width by EM simulation. 1.case: 80 cells/wavelength: S11: -40dB 2.case: 180 celss/wavelength: S11: -55dB in both cases, it is "matched", and 180 cells/wavelength give better results. At this step, you can conclude that: 80cells/wavelength is enough, because in reality for really good calibration, VNA only gives best result of -65dB (this is the best result we got in LAB), so we cannot distinguish the differences. Now, i apply this method into my real circuit, the 50Ohm Coupler. Figure1: coupler with 80cells (Bold lines is 80 cells, and thin line is 180cells) Figure2: coupler with 180cells As you can see, now the difference is dramatically visible. We care about the matching condition (S33), coupling (S31), and isolation(S41) of Coupling branch. There is no change in S31, but S33 and S41 change alot. For 180 cells, S33 is matched, but with 80 cells, in my opinion, it is not matched. So, my question is, which values should we rely on? I attached my workspace for you if you need some checks Best Regards, Rinc附件coupler_180cells.PNG79.5 KBcoupler_80cells.PNG81.0 KBCoupler.7zap3.1 MB
2019-02-19 06:15
你好。我拥有一台DSO-X 2002A 2通道70MHz 2 GSa / s示波器，我正试图通过发射器/接收器P波换能器在岩石核心内的某些边界的反射上进行双向传播。问题是我只看到示波器显示屏上的脉冲。我检查了电缆是否连接在正确的端口，经过了所有可能的配置（Itried改变波的频率，幅度，增益，阻尼，高通和低通滤波器等等，它仍然没有给我一个值得分析的信号）。我的岩石核心长度为6.5厘米，p波速度略高于4000米/秒，其中第一个也是最重要的边界是在第一个1厘米之后，尽管应该给出最高阻抗的边界是边界它的核心和铝板下面（6.5厘米），我在信号中看不到。 prtscr.jpg是脉冲发生器的规格; sig_inter.png是没有核心连接到传感器的信号; dig_read_inter.png是核心连接到传感器的信号。任何人都可以帮我弄清楚为什么我无法看到边界反射的正确信号？干杯! sig_inter.png22.0 KBprtscr.jpg112.6 KB 以上来自于谷歌翻译 以下为原文Hello. I possess a DSO-X 2002A 2 channel 70MHz 2 GSa/s oscilloscope and I'm trying to two way travel time's on reflections in some boundaries within a core of rock through a transmitter/receiver P-wave transducer. The problem is that I only see the impulse on the oscilloscope's display. I've checked the cables are connected in the right port's, went through all of the configurations possible (Itried to change the wave's frequency, amplitude, gain, damping, high and low pass filters and so on and it still isn't giving me a signal worth analyzing). My core of rock has 6,5cm lenght, p-wave velocity is a tiny bit higher than 4000m/s and the first and most importante boundary within it is just after the first 1cm although the boundary that should give the highest impedance is the boundary of the core and the aluminum plate it has underneath (at 6,5cm) which I don't see either in the signal. prtscr.jpg is the specs for the pulser; sig_inter.png is the signal without the core attached to the transducer; dig_read_inter.png is the signal with the core attachedto the transducer. Can anyone help me figure out why I haven't been able to see a proper signal with the boundaries reflections? Cheers!附件sig_read_inter.png25.3 KBsig_inter.png22.0 KBprtscr.jpg112.6 KB
2019-02-19 12:49
软性显示器的构造包括那几部分软性显示器有哪几种型态软性显示器技术的发展潜力
2021-04-26 07:01
