I am trying to design a gps data logger. I am not able to comprehend the chip antenna layout given here.
The pads 1 & 2 in the layout share the same terminal? Isn't it same as connecting the feed line to GND?
You are correct that Pads 1 & 2 in the diagram share the same terminal, however this is not the same as connecting DC ground on both ends of the antenna. This is how the magnetic field is coupled into the antenna. The electric field travelling in the substrate is referenced to both the ground vias which is a coplanar waveguide mode of propagation. This RF short circuit forces a magnetic field to exist at the antenna pad and excites the resonant mode in the dielectric resonator antenna.