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arXiv · 2603.08962

Mitigation of UE Antenna Calibration Errors via Differential STBC in Cell-Free Massive MIMO

Marx M. M. Freitas·Stefano Buzzi
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Abstract

This letter investigates the use of differential space-time block coding (DSTBC) to address antenna array calibration impairments at multi-antenna user equipment (UE) in the downlink (DL) of cell-free massive MIMO (CF-mMIMO) systems. We show that, by exploiting DSTBC, reliable DL communication can be achieved without explicit UE-side calibration or channel phase knowledge. Simulation results demonstrate that the proposed DSTBC-based transmission effectively mitigates the impact of antenna-dependent phase offsets, restoring near-coherent performance in CF-mMIMO networks.

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Marx M. M. Freitas, Stefano Buzzi. 2026-03-09. Mitigation of UE Antenna Calibration Errors via Differential STBC in Cell-Free Massive MIMO. https://arxiv.org/abs/2603.08962

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