Open AccessAnalogue predistortion lineariser control schemes for ultra‐broadband signal transmission in 5G transmitters
Author(s) -
Gumber Karan,
Rawat Meenakshi
Publication year - 2020
Publication title -
iet microwaves, antennas and propagation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.555
H-Index - 69
eISSN - 1751-8733
pISSN - 1751-8725
DOI - 10.1049/iet-map.2019.0253
Subject(s) - baseband , predistortion , electronic engineering , broadband , amplifier , bandwidth (computing) , computer science , engineering , telecommunications
Analogue predistorter (APD) has gained a new significance due to the need for high bandwidth in the fifth generation (5G) communication. As predistorted signal is generated in the analogue domain, it is free from data converter bandwidth limitation and presents an attractive linearisation solution for power amplifier (PA) in the 5G base station. Furthermore, it also finds its application in the multicarrier repeater system for long‐distance communication, where the baseband information is not readily available. However, the performance of the conventional APD is dependent on the appropriate control of gain and phase of the predistorted signal. The state‐of‐the‐art work in analogue linearisation solutions mostly utilises vector multiplier for such a control. This work points out the limitations of such a scheme and proposes a novel control scheme (CS) that is capable of extracting better benefits of the APD. An experimental validation is carried out by linearising 10 W HMC8500 broadband GaN PA, excited by a eight‐component carrier 160 MHz ultra‐broadband long‐term evolution signal. The proposed Type‐II CS delivers an adjacent channel power ratio of −45.05 dBc with an improvement of 18 dB, which is 4 dB better than Type‐I CS.