I'm reviewing AppNote 3248, "Using the MX1321x Internal Transmit/Receive Switch in a Low-Cost, Single-Port, Two Layer Design." I am not an RF engineer and I'll happily copy a tested design.
I'm curious about a feature of the design. Just before the antenna, the signal is sent through R111, which apparently is a zero ohm resistor.
Now, I'm a digital guy and anything analog is black magic to me. But I've just got to ask: what is the purpose of a zero-ohm resistor?