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Title: Minimizing Pilot Overhead in Cell-Free Massive MIMO Systems via Joint Estimation and Detection
We propose a joint channel estimation and data detection (JED) algorithm for cell-free massive multi-user (MU) multiple-input multiple-output (MIMO) systems. Our algorithm yields improved reliability and reduced latency while minimizing the pilot overhead of coherent uplink transmission. The proposed JED method builds upon a novel non-convex optimization problem that we solve approximately and efficiently using forward- backward splitting. We use simulation results to demonstrate that our algorithm achieves robust data transmission with more than 3x reduced pilot overhead compared to orthogonal training in a 128 antenna cell-free massive MU-MIMO system in which 128 users transmit data over 128 time slots.
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Award ID(s):
1717559 1652065
Publication Date:
Journal Name:
IEEE 21st International Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
Page Range or eLocation-ID:
1 to 5
Sponsoring Org:
National Science Foundation
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