Some questions about GaAs HBT RF PA about cellphone

welcome come here discuss with me

I want to design a RF PA which used in cellphone ,this cellphone used in GSM850,GSM900,DCS1800 and PCS1900.we want to use GaAs HBT.this PA contain a PA and a power control block(in CMOS).

I used design PA for BT2.4G in CMOS,So i don't know much about this PA,do you have any idea about this PA,such as PA and power control.

can you introduce me some useful book or documents about GaAs PA used in cellphone

so appreciation!