Broadband Highly Efficient and Linear Power Amplifiers for Next-Generation RF Front-Ends

Frequency-band proliferation has become a signature of modern wireless communications, such as 4G Long Term Evolution (LTE) systems, due to the insatiable need for spectrum resources. To cover such a rapidly growing number of fragmented spectra, RF power amplifiers are generally expected to operate linearly and efficiently over a significantly extended bandwidth often spanning beyond octave. Recent advances show that continuous Class-F and inverse Class-F modes offer a solid solution to design and realize broadband PAs. In this talk, we will present our latest research on broadband PA technologies based on advanced matching network synthesis together with dynamically combined continuous modes, namely mode transferring. This mode-transferring technology leads to substantially expanded design space, demonstrated by state-of-the-art broadband PA performance. By further extension, we will show that reconfigurability can be incorporated into the broadband PA design, leading to enhanced back-off efficiency and good linearity. It offers a promising solution to support future-generation (5G) ultra-high data-rate communication systems.