question related to mixer design

[nisha gupta]

why LC load is preferred in upconversion mixer and RC load in downconversion mixer

 

[BigBoss]

Up conversion=Output frequency is high,inductors haven't-practically-series resistors,more voltage headroom is available
Down Conversion=Output Frequency is low,inductors are bulky and not practical,amplification is easier after mixer,voltage headroom has second priority..
You can consider also Noise and Nonlinearity in according with them.

 

[vfone]

LC network can provide a better a Low Pass rejection, which is mandatory in up-conversion.