Class AB vs. class J 5G power amplifier in 28-nm UTBB FD-SOI technology for high efficiency operation

Abstract

Nowadays, technological demands are exponentially and rapidly growing. The telecommunication market examines a growing demand for RF mobile devices where high latency performances are targeted. The power amplifier is a major element of the radio frequency front-end especially if power consumption and bandwidth are considered. This paper presents the design of mm-wave power amplifier for the candidate of 5G using both Common Source Class-AB and Class-J topologies by means of the 28-nm UTBB FD-SOI technology under body bias technique. Upon taking into consideration the parasitic extraction of the transistor, RF pads, and interconnection to ground, a comparison is made and the theoretical effectiveness of Class-J topology for single stage large signal amplification is simulated practically. Moreover, two distinct transistor widths 250 μm and 350 μm are simulated where each has its own topology to study the impact of increasing the width on the performance of the Power Amplifier. While 5G spectral band is not yet specified and determined; recent studies proved that the 28 GHz band is particularly effective for 5G mobile standardization. Thus, the 28 GHz band is chosen as the fundamental frequency of the operation for this work.