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Is mixer's 2RF-LO spur euqal to its 2IF+LO spur?

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tony_lth

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I have a mixer, and I want to know what level is of the 2IF+LO spur compared to the IF+LO level.
The datasheet of the mixer doesn't have 2IF+LO spur sheet at RF port, but have mRF+nLO spurs sheet at IF port .
Can I calculate the 2IF+LO spur at RF from the datasheet?
 

vfone

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In a dual-balanced mixer, 2*IF+LO has lower level than IF+LO, whatever type of LO injection is used (lower side, or upper side).
 

tony_lth

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The mixer is double balanced mixer ICs with integrated LO amplii ers. This mixer can operate as an upconverter or downconverter. And the spurs table is as following. Any way to calculate the spur level of LO+2*IF?
 

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tony_lth

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LO is lower side. The RF=LO+IF, and I want to know the spur level of LO+2*IF?
 

vfone

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There is no formula which predicts exactly the level of spurious at the output of a mixer.
You only can simulate, or measure.
Simulation is based on a complex calculation, which includes the characteristics of the semiconductor components used, input levels, matching impedances, shape of input waveforms, etc.
 

biff44

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go to a popular website (marki, mini circuits, etc) and find an equivalent mixer, and use its spur table as a rough guide.

If it is really critical, make the measurement yourself using the exact same topology (filters, pads, amplifier, etc) as in your final system.
 
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