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We present the Hybrid Polar Decoder (HyPD), a hybrid classical-quantum decoder design for Polar error correction codes, which are becoming widespread in today’s 5G and tomorrow’s 6G networks. HyPD employs CMOS processing for the Polar decoder’s binary tree traversal, and Quantum Annealing (QA) processing for the Quantum Polar Decoder (QPD)-a Maximum-Likelihood QA-based Polar decoder submodule. QPD’s design efficiently transforms a Polar decoder into a quadratic polynomial optimization form, then maps this polynomial on to the physical QA hardware via QPD-MAP, a customized problem mapping scheme tailored to QPD. We have experimentally evaluated HyPD on a state-of-the-art QA device with 5,627 qubits, for 5G-NR Polar codes with block length of 1,024 bits, in Rayleigh fading channels. Our results show that HyPD outperforms Successive Cancellation List decoders of list size eight by half an order of bit error rate magnitude, and achieves a 1,500-bytes frame delivery rate of 99.1%, at 1 dB signal-to-noise ratio. Further studies present QA compute time considerations. We also propose QPD-HW, a novel QA hardware topology tailored for the task of decoding Polar codes. QPD-HW is sparse, flexible to code rate and block length, and may be of potential interest to the designers of tomorrow’s 6G wireless networks.
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The Design and Implementation of a Hybrid Classical-Quantum Annealing Polar Decoder
We present the Hybrid Polar Decoder (HyPD), a hybrid of classical CMOS and quantum annealing (QA) computational structures for decoding Polar error correction codes, which are becoming widespread in today’s 5G and tomorrow’s 6G networks. HyPD considers CMOS for the Polar code’s binary tree traversal, and QA for executing a Quantum Polar Decoder (QPD)–a novel QA-based maximum likelihood submodule. Our QPD design efficiently transforms a Polar decoder into a quadratic polynomial optimization form amenable to the QA’s optimization process. We experimentally evaluate HyPD on a state-of-the-art QA device with 5,627 qubits, for Polar codes of block length 1,024 bits, in Rayleigh fading channels. Our results show that HyPD outperforms successive cancellation list decoders of list size eight by half an order of bit error rate magnitude at 1 dB SNR. Further experimental studies address QA compute time at various code rates, and with increased QA qubit numbers.
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- Award ID(s):
- 1824357
- PAR ID:
- 10357374
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 978-1-6654-3540-6
- Format(s):
- Medium: X
- Location:
- Rio de Janeiro, Brazil
- Sponsoring Org:
- National Science Foundation
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