校准后S21纹波无法消除

0.05 dB纹波实际上非常小，校准过程中电缆和/或电缆的移动很容易成为问题的根源。
您使用的是高质量的相稳定电缆吗？
您是否将它们固定在工作台上以最大程度地减少校准步骤期间以及之后连接到DUT时的移动？
这些快速噪音般的涟漪还是类似于驻波？
消除噪声是罪魁祸首的可能性，在校准期间打开10-20扫描平均值和/或降低IFBW。



     以下为原文

  0.05 dB ripple is actually very small and bad cable and/or cable movement during calibration can easily be the source of the problem.  Are you using high quality phase stable cables?  are you securing them to the work surface to minimize movement during calibration steps and afterwards when you connect to the DUT?  Are these fast noise-like ripples or do they resemble a standing wave?  to eliminate the possibility that noise is the culprit, turn on 10-20 sweep averages and/or reduce the IFBW during the calibration.

我们使用的是测试级Mega Phase电缆，连接校准标准之间似乎没有超过6英寸的移动。
校准期间和DUT的测量范围在3英寸直径范围内。
IFBW在1kHz时非常低，但我们可以尝试进一步降低它。
由于纹波在位置上相当稳定，所以平均似乎没有多大意义。
波纹看起来不像驻波，它更像锯齿。



     以下为原文

  We are using test grade Mega Phase cables and there doesn't seem to be more than 6 inches of movement between connecting cal standards.  The measurement during calibration and of the DUT are within a 3in diameter area.  The IFBW is quite low at 1kHz, but we can try lowering it further.  Averaging doesn't seem to do much which makes sense since the ripple is quite stable in position.  The ripple doesn't look like a standing wave, it's more saw tooth.

我可以做的另一个建议是使用PNA的引导校准和执行和未知直通校准。
这将消除适配器移除所需的所有额外步骤。
您基本上会在每个端口上执行OSL，然后将两根电缆连接到任何直通适配器（只要它的损耗小于40 dB）。
如果您有一个2端口PNA-L型号，那么您可以直接执行此操作，但如果您有4端口型号，则必须执行宽带第1层校准，我们称之为“全球三角洲匹配”（更多信息_
*这里*_ ）。



     以下为原文

  Another suggestion I can make is to use the PNA's Guided cal and perform and Unknown Thru calibration.  this will eliminate all the additional steps needed for the adapter removal.  you'll essentially do a OSL on each port and then connect the two cables with any thru adapter (as long as it has less than 40 dB of loss).  If you have a 2-port PNA-L model then you can do this directly, but if you have 4-port model you'll have to perform a broadband 1st tier calibration that we call the "Global Delta Match" (more info _*HERE*_ ).

> {quote：title = daras写道：} {quote}> 0.05 dB纹波实际上非常小，校准过程中电缆和/或电缆的移动很容易成为问题的根源。
Em，有趣的daras，你说+/- 0.05 dB很小，因为Joel表示我的S21纹波在+/- 0.02 dB处于良好的极限。
这看起来是否过度波动？
什么值得注意的？
我使用的设备比Dave_11要差一些，后者有PNA。
我有* 8720D VNA * 85032B N校准套件* Agilent 85131F VNA电缆，带3.5 mm到N的适配器。
（但我只工作到6 GHz，而不是8.5到11.5 GHz）使用我的8720D VNA，85052B 3.5 mm校准套件和Agilent 85131F VNA电缆，我似乎无法获得比+/- 0.02 dB更好的效果，
我试图尽可能保持。
事实上，0.02 dB似乎是一个好日子，但我通常可以做到+/- 0.05 dB。
我希望我能够更好地使用85052B中的滑动负载。
当我使用该套件作为光荣的85052D，这是原始海报（Dave_11）。
*（我很乐意看到安捷伦或Maury Microwave制作一些关于使用滑动载荷和验证套件的视频）*。
也许有滑动负载我可以做得更好。
戴夫



     以下为原文

  > {quote:title=daras wrote:}{quote}
> 0.05 dB ripple is actually very small and bad cable and/or cable movement during calibration can easily be the source of the problem. 

Em, 
interesting daras that you say +/- 0.05 dB is small, since Joel indicated my S21 ripple at +/- 0.02 dB was on the limits of being good. 

Does this look to be excessive ripple? What caues it? 

I was using somewhat more antiquated equipment than Dave_11, who has a PNA. I had

* 8720D VNA
* 85032B N calibration kit
* Agilent 85131F VNA cables with 3.5 mm to N adapters. 

(But I was only working up to 6 GHz, not 8.5 to 11.5 GHz)

I can't ever seem to get any better than about +/- 0.02 dB with my 8720D VNA, 85052B 3.5 mm cal kit and Agilent 85131F VNA cables, which I try to keep as still as possible. In fact, 0.02 dB seems a good day, but I can usually do better than +/- 0.05 dB. 

I wish I was more confident of being able to use the sliding loads in my 85052B properly. At the minute I'm using the kit as a glorified 85052D, which is what the original poster (Dave_11) has. *(I would love to see Agilent or Maury Microwave produce some videos about using sliding loads and verification kits)*. Maybe with sliding loads I could do better. 

Dave