测量航空公司的S11和S21时的结果很奇怪

你没有说短1和短2之间的条件有什么不同（可能是两个不同的短标准）。
你没有说你的测试设置，但我认为它有一个测试端口电缆。
细纹波纹是由于电缆不良造成的。
根据细粒纹波的频率，您可以计算电缆长度。
缓慢的纹波是由于cal-kit错误造成的。
+ -0.3 dB的纹波意味着您具有-30 dB的源匹配和方向性误差的组合。
可能每个都大约相同，每个约为-36 dB。
我认为85032A校准套件是较旧的，它看起来只有2 GHz。
因此，它可能具有低频带负载，其调谐到2GHz并且在较高频率下具有较差的性能。
这可能是“你得到的是你付出的，而不是你所希望的”。



     以下为原文

  You don't say what is the difference in conditions between short 1 and short 2 (maybe two different short standards).  You don't say your test setup but i presume it has a test port cable.

The fine grain ripple is due to a bad cable.   From the frequency of the fine-grain ripple you can compute your cable length.  The slow ripple is due to cal-kit error. The ripple of +-0.3 dB means you have a combination of source match and directivity error of -30 dB.  It could be that each is about the same, and each is about -36 dB.

I think the 85032A cal kit is the older one and it looks to be specified to only 2 GHz. Thus it might have a low-band load which is tuned to 2 GHz and has poorer performance at higher frequencies.  It might be a case of "you get what you pay for, not what you hope for".

那是Joel，我犯了一个错误，我使用的是85032B。
关于端口设置，我使用两根APC7电缆Suhner sucoflex 100和两个Agilent APC7到N适配器。
使用相同的短标准在不同时间拍摄照片之间的差异。
所以这些结果告诉我，使用这些电缆，我将无法验证校准？
我确实在那些电缆的末端进行了校准，为什么我会放大？
编辑：theamberco于2014年8月13日上午11:12编辑：theamberco于2014年8月13日上午11:16



     以下为原文

  That's Joel, I made a mistake I was using the 85032B. With respect to the port setup I was using two APC7 cables Suhner sucoflex 100 with two Agilent  APC7 to N adapters.
The difference between the pictures were taken at different times with the same short standard.
So those results are telling me that with those cables I wont be able to verify the calibration?. I did calibrate at the end of those cables, why a I getting amplification?

Edited by: theamberco on Aug 13, 2014 11:12 AM

Edited by: theamberco on Aug 13, 2014 11:16 AM

所以你看到由于电缆坏而导致的高速纹波消失了。
低速纹波几乎可以肯定是由于负载，可能只指定并调整到2 GHz。
高达2 GHz的纹波为0.08，表示残余为-40 dB的总误差。
如果负载为-46 dB，则会产生此错误（因为负载中的误差会同时指向方向性和源匹配，并且测量线路末端的短路会在最坏情况下添加这些错误。
峰）。
并且航空公司可能存在错误以及未正确处理（您必须小心如何设置差距，这会产生影响）。
此外，这些套件必须小心处理以避免连接器重复性错误，最后，两个端口本身可能具有不同的特性，因此我认为这是您使用这些老式机械套件所获得的。
这就是今天每个人都使用Ecals的原因！
根据我对校准套件的理解，这些结果并不出乎意料。
你将需要一个更高频率的calkit，以便在高频率下获得更好的结果。



     以下为原文

  So you see the high speed ripple, which is due to the bad cable, is gone.

The low speed ripple is almost certainly due to the load, which is likely only specified and tuned to 2 GHz. The ripple up to 2 GHz is 0.08 which represents a total error of -40 dB residual. If the load were -46 dB, it would give this error (since the error in the load goes to both the directivity and the source match, and measureing the short at the end of a line gives the worst case addition of these errors at the peak).  And there can be errors in the Airline as well as not proper handling (you have to be careful how to set the gap, and it's affect).

Further, these kits have to be handled carefully to avoid connector repeatability errors, and finally, the two ports themselves could have different characteristics, so I think this is what you get with these old-fashioned mechanical kits.  That's why everyone uses Ecals today!

These results are not unexpected, according to my understanding of the cal kit.  you will need a higher frequency calkit to get better results at high freqeuncy.

谢谢，但使用的套件是85032B到6Ghz，但你说Ecal比机械套件更好？
我将尝试获取一个Ecal或另一个更高频率的套件，然后尝试。



     以下为原文

  Thanks, but the kit used is the 85032B goes to 6Ghz but you are saying that Ecal is better than mechanical kits? I will try to fetch one Ecal or another higher frequency kit then and try.

0.06dB p-p纹波表示约-49dB的总残差，推断出约-55dB的负载质量。
正是人们所期待的。
良好的负载可以带来更好
高速纹波看起来像微量噪声。
提高功率或降低IF BW以消除0.05 dB噪声误差。
我推荐1 kHz IFBW。
另外，你使用扭矩扳手吗？
他们需要获得高质量的测量结果。
而且您可能也需要清洁连接器。
一点点污垢会改变配合距离并限制质量。
但是，对于短路的反射测量，改进超过0.06 dB意味着您处于计量领域。
在这种情况下，您还必须知道频率低端的纹波有点预期，因为航空公司阻抗随频率不恒定，但由于非无限导电率的趋肤效应而在较低频率处增加。
根据航空公司的长度，您必须处理中心导体不是精确居中的事实，而是在中间下垂导致线路阻抗发生变化。
这一切都在计量实验室中得到了解决（它实际上形成了一条悬链曲线，就像金门大桥上的电缆一样）。



     以下为原文

  That 0.06 dB p-p ripple represents a total residual of about -49 dB, inferring a load quality of about -55 dB.  So exactly what one would expect.  Good loads give better results.  The high speed ripple looks like trace noise. Raise the power or lower the IF BW to remove that bit of 0.05 dB noisy error.  I recommend 1 kHz IFBW.  Also, do you use torque wrenches?  They will be needed to get high quality measurements than this.  And you will likely need to clean your connectors as well. A little bit of dirt can change the mating distance and limit the quality.  But improving beyond 0.06 dB for reflection measurements of shorts means you are in the realm of metrology.  In this case, you also have to know that the ripple at the low end of the frequency is a little expected as the airline impedance is not constant with frequency, but increases at lower frequency due to skin effect of not infinite conductivity.  And depending upon the length of the airline, you have to deal with the fact that the center conductor is not exactly centered, but droops in the middle causing a change in impedance of the line. This is all accounted for in metrology labs (it forms a catenary curve in fact, just like cables on the golden gate bridge).

最大的区别是IF BW和滑动负载。
我注意到2 GHz附近的迹线发生了离散跳跃，我认为这是由于你使用滑动负载进行校准。
滑动负载比固定负载好得多，因此在2 GHz以上您会看到较少的纹波，因为滑动负载设置了方向性和源匹配。
顺便说一句，第一篇帖子显示了这张照片。
我不知道如何删除重复的帖子。



     以下为原文

  The big difference is IF BW and sliding load.  I noticed a discrete jump in the trace near 2 GHz, and I presume that is due to you using a sliding load for the calibration. The sliding load is much better than the fixed load, so above 2 GHz you see less ripple because the sliding load sets the directivity and source match.  

BTW, the first posting showed the picture.  I don't know how to delete repeated postings either.