Abstract: Highly efficient power amplifiers (PAs) and associated linearization techniques have been developed to accommodate the explosive growth in the data transmission rate and application of massive multiple input multiple output (mMIMO) systems. In this paper, energy-efficient integrated Doherty PA monolithic microwave integrated circuits (MMICs) and linearization techniques are reviewed for both the sub-6 GHz and millimeter-wave (mm-Wave) fifth-generation (5G) mMIMO systems; different semiconductor processes and architectures are compared and analyzed. Since the 5G protocols have not yet been finalized and PA specifications for mMIMO are still under consideration, it is worth investigating novel design methods to further improve their efficiency and linearity performance. Digital predistortion techniques need to evolve to be adapted in mMIMO systems, and some creative linearity enhancement techniques are needed to simultaneously improve the compensation accuracy and reduce the power consumption.

面向大规模MIMO系统的高效功率放大器及其线性化技术综述

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