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arXiv · 2607.24227

Beam-Domain Channel Estimation for mmWave MIMO using Sub-6 GHz Out-of-Band Information

Faruk Pasic·Mariam Mussbah·Stefan Schwarz·Markus Rupp
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Abstract

Future wireless multiple-input multiple-output (MIMO) systems will integrate sub-6 GHz and millimeter wave (mmWave) bands to support high data rates for latency-critical applications. The coexistence of these bands enables the use of reliable out-of-band sub-6 GHz information to assist mmWave link establishment, particularly for channel estimation. In this paper, we propose a novel beam-domain channel estimation method for mmWave MIMO that leverages sub-6 GHz beam-domain information to improve estimation accuracy. We compare the proposed method with conventional in-band methods. Simulation results show that our proposed method outperform existing baselines in terms of spectral efficiency, in both line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios.

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Faruk Pasic, Mariam Mussbah, Stefan Schwarz, Markus Rupp. 2026-07-27. Beam-Domain Channel Estimation for mmWave MIMO using Sub-6 GHz Out-of-Band Information. https://arxiv.org/abs/2607.24227

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