怎么在PNA-X上使用-088进行有效负载牵引

是的，要在DUT参考平面上获得精确测量，您必须进行2端口引导功率校准。端口2校准信息通知固件第二个端口的丢失和延迟，以便可以创建正确的匹配状态
。
如果没有calibraiton，数据将看起来正常，因为有效负载会将负载值（a2 / b2）强制为所需的值，但a2和b2的读数有错误，因此负载的真实值也会出错。
引导功率校准增强了正常的2端口校准，不仅可以校准S参数，还可以校准接收器，信号源和接收器比率。



     以下为原文

  Yes, to get accurate measurements at the DUT reference plane, you must do a 2-port guided power calibration..  The port 2 calibration information informs the firmware on the loss and delay of the second port so that the proper matching state can be created.

Without calibraiton, the data will look OK, as the active load will force the load value (a2/b2) to the value desired, but the readings of a2 and b2 have errors, so the true value of the load will also have errors.  The guided power calibration enhanced the normal 2 port calibration to calibrate not only S-parameters, but receivers, sources, and receiver ratios as well.

谢谢乔尔博士！
这很有道理。
虽然帮助文件告诉您要按什么按钮（或要发送什么命令），但如果安捷伦制作了关于该技术的简短应用说明，那将会很棒。
我们获得的结果给我留下了非常深刻的印象，它使我们能够快速确认我们的一个放大器设计的行为。
这是一个非常有用的功能 - 其中一个很棒的功能是它可以从前面板'手动'使用，或者自动化 - 所有这些都是以滑动螺丝调谐器的价格出售的！
再次感谢andy



     以下为原文

  Thanks Dr Joel!  That makes perfect sense.

Whilst the help file tells you what buttons to press (or what commands to send), it would be great if Agilent produced a short application note on the technique.  I was very impressed by the results we obtained and it allowed us to quickly confirm behaviour of one of our amplifier designs.  It is a very useful capability - one of the great things is that it can be used 'manually' from the front panel, or automated - and all for the price of a slide-screw tuner!

Thanks again

andy

你好Dr_Joel等，也许我在考虑这个问题......使用源代码控制的史密斯圆图覆盖范围有多“好”？
我感兴趣的是 - 考虑到具有源/接收器校正的2端口校准，我可以准确地合成多大的回波损耗（对于符号迂腐）吗？
我可以合成一个15 dB的回波损耗，一个20 dB的回波损耗，一个30 dB的回波损耗....鉴于我不会确切地知道负载匹配项（负载匹配的残余误差？）....或者放另一个
有什么方法可以验证校准/有源负载拉动操作？
我的简单尝试是设置相位控制，扫描0-360 @固定频率。
然后我测量了3.5mm THRU的S11（执行Ecal：2port后用src / rx cal）。
我希望看到S11变化，因为我改变了我的有效负载的大小，但它仍然坚持在-38 dB。
如果我关闭了cal（并失去了所有良好的不匹配校正），我现在可以看到有效负载。
我在N5242A上运行A.9.50.13 ....所有内省的原因是我获得的带有和不带校准的放大器负载拉的结果。
任何想法，安迪



     以下为原文

  Hello Dr_Joel et al,

Maybe I am thinking about this too much...  How 'good' is the Smith Chart coverage using source control?  What I am interested in is - how large a return loss (being pedantic about signs) can I synthesize accurately - given a 2port cal with source/receiver correction?  Can I synthesize a 15 dB return loss, a 20 dB return loss, a 30 dB return loss....  Given that I will not know the load match term exactly (residual error of load match?)....

Or put another way, is there any way I can validate the calibration/active load pull operation?

My simplistic attempt was to set up the phase control, sweeping 0-360 @ fixed frequency.  Then I measured the S11 of a 3.5mm THRU (after performing Ecal: 2port with src/rx cal).  I was hoping to see S11 vary as I changed the magnitude of my active load but it stayed doggedly at -38 dB.  If I turn the cal off (and lose all that good mismatch correction), I can now see the active load.  I am running A.9.50.13 on an N5242A....

The reason for all the introspection is the results I obtain for an amplifier load pull with and without calibration.  

Any thoughts,

andy

因为它是actvie，你可以覆盖整个史密斯圆图，甚至可以超越它。
对于非常小的反射（信号小于约-20 dB），您必须将端口2衰减器设置为更高的值。
这是因为如果在扫描中发现实际负载匹配非常小的点，则必须将源2设置得非常小以获得小负载（例如-40 dB回波损耗）。
使用0 dB衰减器时，源不能设置得很小。
有趣的是，您可以通过使用第二个VNA，设置为CW模式，以及在活动加载模式下测量端口2的S11来调整结果。
你必须锁定两个引用togehter。
但是会发生什么是088 VNA将测量输入信号并为其创建有效负载。
测量VNA不知道大约088，因此只显示有效有效负载。
您不能只将端口1连接到端口2，因为088 VNA知道它处于活动负载模式，并且将显示DUT的S参数，并且完全打开2端口，从而解除端口2源的影响
来自S11测量。
您可能会创建一个具有两个1端口校准的通道，但我不记得我们是否支持088。



     以下为原文

  Because it is actvie, you can cover the entire Smith chart and even go outside of it.

For very small reflections (signals less than about -20 dB) you really must set the port 2 attenuator to a higher value.  That is because if you find a point in the sweep where the actual load match is very small, then the source 2 must be set very very small to get a small load (say -40 dB return loss).  The source can't be set that small with the 0 dB attenuator.

Interestingly, you can vaildate your result by using a second VNA, set to CW mode, and measure S11 of port 2 while in active load mode.  You have to lock the two references togehter.  But what will happen is the 088 VNA will measure the input signal and create an active load for it.  The measuring VNA doesn't know about 088 and so just shows the effective active load.

You cannot just connect port 1 to port 2, as the 088 VNA knows it is in active load mode, and will show the S-parameters of the DUT with full 2 port cal on, and thus de-embed the effect of port 2 source from the S11 measurments.   You might get away with creating a channel with two 1-port calibrations, but I don't remember if we support that in 088.