VSWR峰值取决于使用的点数

可能有几个原因。
不幸的是，我们需要了解更多信息。
1.您是否使用与进行测量时相同的点数来执行开路，短路，负载校准（或ECal）？
如果没有，那么你正在使用插值，这可能会导致问题，尤其是在宽扫描等问题上。
这是大多数迹线上较小的尖刺的原因。
2.您是否启用了步进扫描？
默认情况下，未启用步进扫描，除非启用，否则我们不保证+任何+。
注意：使用1KHz或更低的IFBW将自动使用步进扫描，即使它尚未启用。
大穗可能是由于带交叉造成的。
如果不遵循上述第1项和第2项，这将使情况更糟。
我现在在家，不知道这是不是乐队的交叉。
服务目录中有一个名为ShowBandInfo的程序，它将列出所有的带交叉。
要避免此问题，请在1601,3201或更高的许多点执行用户校准;
特别是这种频率扫描。
使用1KHz或更低的IFBW执行校准。
如果这对你来说太慢了，那么至少打开Stepped Sweep！
完成校准后，您可以以用于校准的点数的子倍数进行测量。
例如，如果您将校准值设置为3201点，则可以在1601,801,401,201等点测量您的测量值。
试试这个，让我们知道结果。
还有其他解决方案，但上面是最简单的。



     以下为原文

  There could be several reasons.  Unfortunately we would need to know a bit more information.  

1. Did you perform your Open,Short,Load cal  (or ECal) using the same number of points as when you made your measurement?  If not, then you are using interpolation, which can cause problems, especially on wide sweeps such as this.  This is the cause of the smaller spiky-ness on most of the trace.

2. Do you have Step Sweep  enabled?  By default, step sweep is NOT enabled and we do not guarantee +anything+ unless it is enabled.  Note: Using an IFBW of 1KHz or less will automatically use step sweep even if it is not already enabled.

3. The large spike could be due to a band cross.  The effect of this will be made worse by not following items 1 and 2 above.  I am at home now and do not know if that is a band cross or not.  There is a program in the service directory called ShowBandInfo that will list all the band crossings.

To avoid this issue, perform your user calibration at a high number of points such as 1601, 3201, or more; especially with this wide of a frequency sweep.  Perform your cal with an IFBW of 1KHz or less.  If this is too slow for you, then at least turn on Stepped Sweep!  Once your cal is done, you can then take your measurements at a sub-multiple of the number of points that you used for the cal.  For example, if you made your cal at 3201 points, you can take your measurement at 1601, 801, 401, 201, etc. number of points.

Try this and let us know the results.  There are other solutions also, but the above is the easiest.

谢谢回复。
我使用Ecal重新校准。
扫描点3201，IF BW 700 Hz。
我使用3201测量然后减少到401进行比较。
现在，尖峰出现在越来越多的点上。
我找不到这个ShowBandInfo ...你能告诉我吗？
再次感谢AJ
3201.PNG29.3 KB



     以下为原文

  Thanks for the reply.

I have recalibrated using Ecal. Sweep points 3201, IF BW 700 Hz. I measured using both the 3201 and then reduced to 401 for comparison. Spike occurs on larger and smaller number of points now.

I couldn't find this ShowBandInfo...can you please let me know?

Thanks again
AJ

附件

• 401.PNG28.3 KB
  
• 3201.PNG29.3 KB
  

我有一种感觉，这是由于电缆的改装...所以在更换电缆后，尖钉消失了。



     以下为原文

  I had a feeling it was due to moding of the cable...so after replacing the cable, the spikes have disappeared.

哦，好......这很容易。
ShowBandInfo程序可能只适用于较新的乐器。
但是你可以从这里下载它：http：//na.support.keysight.com/pna/apps/showbandinfo.exe很高兴，但现在我可以回去做税了。
呸。



     以下为原文

  Oh good...that was easy.
The ShowBandInfo program may only be on newer instruments.  However you can download it from here: http://na.support.keysight.com/pna/apps/showbandinfo.exe

Glad that worked out...now I can get back to doing my taxes. Yuck.