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arXiv · 2609.26150

Fronthaul-Efficient Cell-Free Massive MIMO via Stream-Adaptive Resolution Control

Özlem Tuğfe Demir·Sinan Gezici
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Abstract

We consider the uplink of a fronthaul-constrained cell-free massive MIMO system with a single multi-antenna user equipment (UE) transmitting multiple spatial streams to distributed access points (APs). Due to heterogeneous channel conditions and limited fronthaul capacity, uniform-resolution quantization across APs and streams is highly inefficient. To address this, we propose a stream- and AP-adaptive resolution control framework that jointly optimizes the transmit power and per-AP per-stream quantization resolutions. By leveraging a distributed implementation of singular-value decomposition (SVD)-based processing, the data streams are decoupled at the APs, enabling flexible fronthaul compression across both spatial streams and APs. The resulting non-convex optimization problem is tackled using a weighted minimum mean-squared error (WMMSE)-based block coordinate descent algorithm with semi-closed-form updates.

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Özlem Tuğfe Demir, Sinan Gezici. 2026-08-12. Fronthaul-Efficient Cell-Free Massive MIMO via Stream-Adaptive Resolution Control. https://arxiv.org/abs/2609.26150

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