I'm finding it hard to find an answer for the question, as I'm asking about the circuit's GND, where searching for an answer online or in stack-exchange is coming up with Earth GND for large Antennas such as VHF.
As an example from this application note from Cypress, one antenna has a node connected to system GND like so:
Where as another antenna in the same doc has no connection to system GND:
I don't understand how the antenna can work when it's output is just shorted to GND. Can someone help? Thanks!