IEEE Vehicular Technology Conference

Quantum-Assisted Maximum Likelihood Detection of Generalized Spatial Modulation

Taku Mikuriya, Hyeon Seok Rou, Giuseppe Thadeu Freitas de Abreu, Koji Ishibashi, Naoki Ishikawa

Published Oct 19, 2025• 1 citation

Abstract

We propose a new quantum-assisted maximum likelihood detection (MLD) scheme for generalized spatial modulation (GSM) systems. To that end, we first present a novel MLD formulation for GSM, and then describe a corresponding novel method to prepare the initial state for an associated quantum-computing Grover adaptive search (GAS) algorithm. Simulation results are presented to show that our approach achieves optimal performance and reduces query complexity compared both to the classical MLD and to earlier quantum search methods, which do not achieve an advantage over classical MLD for some parameter settings.

DOI: 10.1109/vtc2025-fall65116.2025.11310105

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