I have found some papers and a description on this topic, I am wondering if anyone has had experience for this use for mobile phone application. Any help/comments would be appreciated.
I think you are refering at what it is known as
"Dielectric Resonator Antenna". I am not sure
but for some 2.4 GHz where the size is small they
called chip antenna.
a simple google search about Dielectric Resonator Antenna
will you a lot of information. There is a profesor
on UMiss who is a specialist on that. You will find
a book reference as well.