flywill
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Hi, Forgive me if the question seems dummy. I know impedance matching in RF design is important for maximum power transfer and min reflection. So that we need input/output Z match. It is a bit easier to understand for out Z match to have max power delivered to load. For input impedance match, it is not very clear. 1. in RX, after 1st stage (LNA), we care only voltage (assume no external components after LNA), so why max power transfer matters as long as max voltage sensed? From LNA until input to ADC, we are amplifying signal voltage, aren't we? 2. with matched input Z, no reflection in the source point, but between matching network to input of chip(assuming matching network done on pcb instead of on-chip), reflection sustains, why it does not matter? 3. if there is input Z mismatch, if max voltage sensed at input stage and amplified in following stages, what is the matter to have matching requirement? 4. what is the bad effect of input mismatch or reflection?
Thanks in advance for any clarification.
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