Envelope Modulator & X-Band MMICs on Highly Integrated 3D Tunable Microcoax Substrate

As next generation wireless communication systems move to higher data rates, the bandwidth (BW) and peak to average power ratio (PAPR) of the signal increase. Envelope tracking power amplifier systems provide a means to efficiently amplify these complex waveforms. Envelope power modulators, which achieve greater than 70% EA efficiency while reproducing the envelope of up to 100MHz (DC-500 MHz envelope bandwidth) LTE signals, paired with various amplifiers are presented with high efficiency and linearity. This result for a wide band signal represents the current record state of the art for envelope tracking high power amplifiers.

I. Introduction

High data-rate wireless communication is essential for future wireless communication systems. As the frequency spectrum becomes increasingly crowded due to civilian, commercial and military use, the wireless carriers have been forced in two directions. First, the spectrum which is currently in use must be utilized more efficiently. Secondly, radios which can operate at carrier frequencies in the tens of GHz (e.g. 5G cellular), where large swaths of unused bandwidth is available, must be deployed. Moving in either of these directions puts strain on the power amplifier (P A) which must be small and power efficient, as weight, size and battery life are a concern in handheld, man-pack, vehicular and airborne terminals.