wideband, broadband. multiband antennas

Archived from groups: alt.cellular.tech,rec.radio.amateur.antenna (More info?)

Hi folks
I'd like to know more about the antennas that are in many of the
multiband cellphones today.
A lot of the phones are multiband,(some are multimode), yet they have
only one antenna.
Would i be correct in assuming that most such phones have an
omnidirectional antenna which is tuned for centerfreq(computed by
considering all the bands for the phone)
If so did the RF frontend designers had to compensate for the fact that
the antenna may have a different vswr at different frequencies...
Or there are dual/tri/quadband antennas in such phones.

Also if you can reccomend some good books/website on this topic that
will be great.
Thanks In Advace
-EOS