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arXiv · 2304.05795

A Low-Complexity Post-Weighting Predistorter in a mMIMO Transmitter Under Crosstalk

Ganesh Prasad·Håkan Johansson
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Abstract

The beam-oriented digital predistortion (BO-DPD) is not sufficient to linearize the output from a subarray of power amplifiers (PAs) in different directions except the desired direction. Therefore, subsequent to the BO-DPD operation, we perform a post-weighting (PW) processing to minimize the nonlinear radiations in the wide range of directions under crosstalk. Here, the optimized PW coefficients are multiplied by the polynomial terms of the BO-DPD, then, the resultant signals are distributed to the PAs to compensate the nonlinear radiations. In this work, first, we propose fully-featured post-weighting (FF-PW) scheme, then, we derive a low-complexity post-weighting (LC-PW) scheme.

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Ganesh Prasad, Håkan Johansson. 2023-04-12. A Low-Complexity Post-Weighting Predistorter in a mMIMO Transmitter Under Crosstalk. https://arxiv.org/abs/2304.05795

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