QUESTION

Question

Hello, which Raptor-Antenna placement would be the better one? GNSS-L1/L5 Band application;some more wireless stuff on the pcb...

Thank's

Fritz

Answer 1

Hi Fritz,

The Raptor antenna does not want to see any PCB ground plane to the left as shown on page 10 of the data sheet. So based on that, the second layout picture would be best.

Please note that the minimal ground plane free clearance underneath the antenna must be 17 x 9.5mm. If by any chance you are able to remove some of the PCB ground to the right of the antenna, then this will only help to improve performance and antenna efficiency, which is important in GPS/GNSS designs.

I would also like to point out that the ground plane clearance underneath the antenna is on every layer of your PCB, and no metal objects like a battery or LCD should be placed directly underneath either.  

Is the IC/module closest to the antenna the GNSS one? For GNSS designs its best to keep the antenna relatively close to the IC/Module so as to reduce the length of the feed trace, otherwise the trace could potentially pick up noise.

Kind regards

Colin

Answer 2

Hello, thank you.

But what with theese suggestions? "Grey" is the battery-pack unterneath pcb.From my oppinion, the first picture (from second post) allows more GND-surface for LoRa-Antenna (right down corner).