I want to build a simple transceiver (half duplex) for 433.92 MHz ASK modulation. I have found a transmitter chip and a receiver chip that I want to use. I want to use the same antenna for RX and TX but I am unsure of how to approach this (The receiver can handle the full output power of the transmitter). I do not want to buy a ready-made circuit for this, I'm doing this mostly to learn.
The antenna is 50 ohms but the receiver and transmitter both have their own impedances and need some matching network. If I used separate antennas this would be simple (say a PI attenuator).
But I’m unsure of how this would work with having both RX and TX on the same antenna. My very naïve approach to this would be to use a splitter/combiner after the matching networks and accept the -3 dB loss from this. This way every side sees 50 ohms.
But this feels very wrong and any input here would be much appreciated!