Integration of RF front-end modules in cellular handsets

The hardware implementation and its evolution of the second generation (2G) cellular handsets have significantly contributed to the tremendous success of wireless communication industries in the past 15 years. The radio portion of the handsets has evolved from a nearly all-discrete implementation towards a very high level of integration in baseband IC, transceiver IC and integrated front-end (FE) modules. This paper first reviews the transceiver architectures of 2G cellular handsets followed by a close examination of the building blocks of RF FE with the exception of power amplifier module (PAM), which is beyond the scope of the current review. The attention is then directed to the enabling technologies leading to RF FE integration. Finally, the migration of handsets hardware to 2.5 generation (2.5G) and third generation (3G) systems is discussed with similar focuses on transceiver architectures, FE hardware implementation and trends in RF FE integration.