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arXiv · 2608.07428

QMIMO: Circuit Based Quantum MIMO Design with Variational Receiver

Sayeda Bipanchi Ahmed·Bikash K. Behera·Mandar Thatte·Prasanta K. Panigrahi
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Abstract

This paper investigates a quantum extension of classical Multiple-Input Multiple-Output (MIMO) communication in which the conventional linear channel model is replaced by a parameterized multi-qubit unitary transformation. Within this framework, interference is represented through coherent quantum interactions rather than additive signal coupling. To recover transmitted information, a Variational Quantum Circuit (VQC) receiver is introduced that learns an approximate inverse channel transformation through supervised variational optimization. The proposed system is evaluated under realistic noisy intermediate-scale quantum (NISQ) conditions incorporating depolarizing noise, thermal relaxation, and measurement imperfections, and its performance is compared with that of standard classical detection methods. The results reveal a trade-off between the two approaches: classical detectors achieve substantially lower bit-error rates across much of the investigated parameter range but exhibit pronounced performance degradation for specific channel configurations, whereas the VQC receiver maintains a more uniform error profile as channel complexity increases, albeit at a higher average BER. These findings suggest that variational quantum receivers are not a direct replacement for classical detection methods, but rather a complementary approach that may offer increased performance stability in communication scenarios characterized by strong coupling and complex interference patterns.

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Sayeda Bipanchi Ahmed, Bikash K. Behera, Mandar Thatte, Prasanta K. Panigrahi. 2026-08-07. QMIMO: Circuit Based Quantum MIMO Design with Variational Receiver. https://arxiv.org/abs/2608.07428

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