robismyname
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My RX Design is as follow:
Stage 1) Low Loss BP Filter: 2.4GHz - 2.483MHz
Stage 2) LNA: 20dB of Gain IP3 of 36dBm
Stage 3) Preselector SAW Filter: 2.4GHz - 2.483GHz
Stage 4) Mixer/Multiplier: assume LO freq and RF freq are in output IP3 of 25dBm
Stage 4a) LO (2260MHz - 2343MHz)
Stage 5) 140MHz IF SAW Filter
etc.
Assuming my LO freq (f1) = 2260MHz and RF freq(f2) = 2400MHz
My hand calculations are telling me that my 2nd order IMD/mixer products will be:
f1 = 2260Mhz
f2 = 2400MHz
2f1= 4520MHz
2f2= 4800MHz
f1+f2 = 4660MHz
f2-f1 = 140 MHz
Considering that I have a 140MHz IF SAW Filter at Stage 5 everything will be attenuated except for f2-f1 correct? Or is there something else I am missing?
Stage 1) Low Loss BP Filter: 2.4GHz - 2.483MHz
Stage 2) LNA: 20dB of Gain IP3 of 36dBm
Stage 3) Preselector SAW Filter: 2.4GHz - 2.483GHz
Stage 4) Mixer/Multiplier: assume LO freq and RF freq are in output IP3 of 25dBm
Stage 4a) LO (2260MHz - 2343MHz)
Stage 5) 140MHz IF SAW Filter
etc.
Assuming my LO freq (f1) = 2260MHz and RF freq(f2) = 2400MHz
My hand calculations are telling me that my 2nd order IMD/mixer products will be:
f1 = 2260Mhz
f2 = 2400MHz
2f1= 4520MHz
2f2= 4800MHz
f1+f2 = 4660MHz
f2-f1 = 140 MHz
Considering that I have a 140MHz IF SAW Filter at Stage 5 everything will be attenuated except for f2-f1 correct? Or is there something else I am missing?
