Wideband. CMOS integrated RF combiner for LINC transmitters

The design of a novel wideband RF signal combiner suitable for LINC transmitters in CMOS technologies is presented in this paper. Compared to the conventional narrowband design, the wideband architecture achieves a small reflection coefficient (less than 0.3) suitable for wideband spread spectrum multi-user mobile systems. A 0.18 /spl mu/m CMOS wideband signal combiner, designed to add two 8GHz signals and deliver 1.5W to the antenna from 1V class F power amplifiers, is presented and compared to a narrowband design.