源衰减器对校准有什么影响

嗨，我已检查首选项检查选项。
但无论是检查还是未检查，回损都是一样的。
当我在PNAx电缆上进行校准时，还有一件事情，那么结果就可以了。
但是当我在PNAx的路径中插入任何类似开关矩阵的设备，然后进行校准@Switch矩阵结束时，就会出现这种问题。
我做错了什么？



     以下为原文

  Hi i have check that preference check option. but return loss is same whether it is check or not checked.

one more thing when i m doing calibration at PNAx cable then result found ok.
but when i m inserting any device like switch matrix in path of PNAx and then doing calibration @ Switch matrix end then such kind of problem is arising.

whether i m doing any thing wrong?

嗯，通常如果您将端口1连接到端口2，并且您已完成校准，则端口1测量端口2匹配并校正负载匹配，因此我应该期望大约-50 dB（不通过Ecal）
只有大约10-15分贝的匹配）。
所以得到-25说已经有些东西了。
如果你的意思是改变端口1衰减器并且S11从-25上升到-10，那么它比我预期的要多。
源匹配更改，但不是方向性。
另一件事可能是你已经卡住了注意器，所以即使端口认为它也没有切换值衰减器。
通过UNCALIBRATED测量，以及从端口1到端口2的通过，将参与者设置为校准的标称值，设置S11和S21跟踪，以及R1,1和B，1跟踪。
标准化（与Data => mem和Data / Mem相同）S21，B和R1;
对于S11，将数据写入mem，数据MINUS mem。
在每条痕迹上放置一个标记。
归一化迹线应读取0 dB，S11应为-70或更高dB。
现在切换衰减器，拍摄所见的屏幕截图，然后将其发回。
标准化迹线应在= -0.5 dB范围内读取相同值，S11应读取低于-50 dB。



     以下为原文

  Hmm, normally if you have port 1 connected to port 2, and you have done a calibration, then port 1 measures the port 2 match and corrects for the load match so I should expect about -50 dB for a thru (not through the Ecal which has only about a 10-15 dB match).  so getting -25 says already something is off. 

If you mean you changes port 1 attenuator and S11 goes up from -25 to -10, then it is more than I expect. The source match changes, but not the directivity.  The other thing could be you have stuck attenutator so the value attenuator doesn't switch even though the port thinks it does. 

With an UNCALIBRATED measurement, and a thru from port 1 to port 2, set the attenautor to the nominal value for the calibraiton, set up an S11 and S21 trace, as well as an R1,1 and B,1 trace.   Normalize (same as  Data=>mem and Data/Mem) S21, B and R1; For S11 do a data into mem, data MINUS mem.  put a marker on every trace.  The normalized traces should read 0 dB, and S11 should be someithing like -70 or more dB.  Now switch the attenuator, take a screen shot of what you see, and post it back. The normalized traces should read the same within =-0.5 dB, the S11 should read below -50 dB.

> {quote：title = KRACK_JACK写道：} {quote}>当我在PNAx电缆上进行校准时，还有一件事就是找到了结果。
>但是当我在PNAx的路径中插入任何类似开关矩阵的设备然后进行校准@Switch矩阵结束时，就会出现这种问题。
>如果开关矩阵是Agilent，型号是多少？
如果没有，请描述一下..>我是否做错了什么？



     以下为原文

  > {quote:title=KRACK_JACK wrote:}{quote}

> one more thing when i m doing calibration at PNAx cable then result found ok.
> but when i m inserting any device like switch matrix in path of PNAx and then doing calibration @ Switch matrix end then such kind of problem is arising.
> 
If the switch matrix is Agilent, what is the model number?  If not, please describe it..
> whether i m doing any thing wrong?

Krack-Jack，根据你对故障的描述，你有两个问题之一。
电缆组件不良或相对端口的负载匹配都会损坏。
如果使用相同的电缆反转测量方向并且更改的响应相同，则可能是电缆不良。
如果衰减器设置的响应变化不大，则端口耦合器，开关或采样器损坏。
如果相同，请尝试另一组电缆。
或者你可能有一个糟糕的E-cal模块！
正如Joel博士所提到的那样，在校准后应该测量质量负载时，应该测量大约40 dB的回波损耗。
戴夫



     以下为原文

  Krack-Jack,

By your description of the failure you have one of two problems.   Either a bad cable assembly or the load match from the opposite port is damaged.   If you reverse direction of your measurement with the same cables and the response from changing is the same, then it may be bad cables.  If the response does not change much with the attenuator setting then it is the either the port coupler, switch or sampler that is damaged.   If the same, try another set of cables.   

Or you could have a bad E-cal module!

As Dr. Joel mentioned, you should have about >40 dB return loss measuring with a quality load applied after calibration.

Dave