Abstract
Development of 5G networks requires a substantial increase to both spectral and power efficiency of transmitters. It is known that these two parameters are subjected to a mutual trade-off. To increase the linearity without losing power efficiency, linearization techniques are applied to power amplifiers. This paper aims to compare most popular linearization techniques to date and evaluate their applicability to upcoming 5G networks. The history of each respective linearization technique is followed by the main principle of operation, revealing advantages and disadvantages supported by concluding the latest research results. Three main groups of linearization methods currently known are feedforward, feedback, and predistortion, each with its own tradeoffs. Although digital predistortion seems to be the go-to method currently, other techniques with less research attention are still non-obsolete. A generalized discussion and a direct comparison of techniques analyzed are presented at the end of this paper. The article offers a systematic view on PA linearization problems which should be useful to researchers of this field. It is concluded that there are still a lot of problems that need to be addressed in every linearization technique in order to achieve 5G specifications.
Highlights
This is expected to utilize a massive amount of MIMO multichannel and multi-standard RF transceivers with a highly integrated density of RF power amplifiers (PA’s), making the PA’s PAE, cost, and small form-factors critical to the mission success of the 5G revolution [3]
This study shows that the peak value of the efficiency curve is sharply defined using more efficient amplifiers
In addition to the standard feedback, a reference signal path is used, which subtracts the main signal from the feedback signal, leaving only the distortions generated by the amplifier
Summary
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. 5G wireless networks will connect a wide range of devices that support a variety of communication standards and bands This is expected to utilize a massive amount of MIMO multichannel and multi-standard RF transceivers with a highly integrated density of RF power amplifiers (PA’s), making the PA’s PAE, cost, and small form-factors critical to the mission success of the 5G revolution [3]. Without the use of any linearization techniques, the amplifier must be used in class A mode with a considerable power back-off, which in turn, significantly reduces the energy efficiency of the system. This problem has been known and solved for a long time, but in order to achieve the goals set by 5G, it is becoming more and more relevant again. This work serves as an in-depth introduction to a wide, deep, and interesting power amplifier linearization problem
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
