# Connecting antenna directly to RF module

I have a general question regarding the connection of an antenna to a RF module like GPS receiver or 433 MHz TXD:

Is a direct connection of an antenna (e.g. GPS ceramic patch) to a module preferred over the regular solution to use a 50 Ohm PCB trace? Or is there more signal reflection, attenuation or other negative impact?

Practically it would look like to have the RF module on the bottom of a PCB and the antenna wire would be fed from the top through a via directly to the antenna pin of the module.

Thanks!

• What do you mean by direct connection to the module? Basically you have to connect the antenna to a 50 ohms "thing" in the module (assuming the antenna impedance is 50 ohms), be it a PCB trace or the transceiver input/output, to avoid reflections. However, you may want to avoid coupling between the antenna and whatever other conductors in the module (which can affect the antenna performance) and so it may be a good idea to place it somewhat far away from other components. Aug 30, 2016 at 16:04

$$Z_{antenna} \leftrightarrow Z_{connection} (via) \leftrightarrow Z_{TX/RX}$$