Tips for measuring harmonics from a transmitter (~1W) with a spectrum analyzer
时间：04-09
整理：3721RD
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Hello,
I need some tips to measure harmonics from a transmitter (~1W) with a spectrum analyzer. I know that I need to use notch or high pass filter to remove the fundamental freq and so avoid the AS input from saturating. My concern is in this case the impedance seen by the transmitter at fundamental. I can use an attenuator to hide the mismatch at fund freq but this would be harmfull for the dynamic range. A circulator is also a solution but I don't have wideband enough.
Do you have any suggestion or test set-up for this measurement?
Thanks a lot.
I need some tips to measure harmonics from a transmitter (~1W) with a spectrum analyzer. I know that I need to use notch or high pass filter to remove the fundamental freq and so avoid the AS input from saturating. My concern is in this case the impedance seen by the transmitter at fundamental. I can use an attenuator to hide the mismatch at fund freq but this would be harmfull for the dynamic range. A circulator is also a solution but I don't have wideband enough.
Do you have any suggestion or test set-up for this measurement?
Thanks a lot.
Apart from analyzer dynamic range, it's spurious IM is most likely the basic issue. Thus filtering of fundamental by higpass or bandstop filter is badly needed. A 10 dB attenuator may be a compromise to keep the transmitter impedance matching within an acceptable range. With usual analyzer senistivity, 20 dB should be possible as well.