Antenna Design For Mobile Devices

Hi all,

I would like to design a flexible PCB antenna which will be use in mobile device, may I know what type of material or substrates which is suitable for such design?

Or is there any other better recommendation of antenna design for mobile device?

Thanks.

Most of the mobile phones use Planar Inverted-F type antennas (PIFA), and the substrate is plastic and air.

Hi, the plastic substrate that you are referring is the casing or the antenna? how about the air?