Laird Connectivity is now EzurioAnswer
The exact figure is difficult to specify, but a rough rule of thumb is that the ground plane size should be about a quarter of a wavelength at 2.5GHz (3 cm in air, less if using FR4 board).
The exact figure is difficult to specify, but a rough rule of thumb is that the ground plane size should be about a quarter of a wavelength at 2.5GHz (3 cm in air, less if using FR4 board).