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arXiv · 2610.17828

Shuf-Scatter: Permutation-Based DLI Suppression for OFDM Ambient Backscatter

Salim Chabani·Riadh Ouzane·Salah Eddine Zegrar·Huseyin Arslan
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Abstract

Direct Link Interference (DLI) remains a major bottleneck in Orthogonal Frequency Division Multiplexing (OFDM)-based Ambient Backscatter Communication (AmBC) systems. This letter proposes Shuf-Scatter, a scheme that applies a deterministic permutation to the reflected OFDM waveform to create a distinct correlation-domain signature. By exploiting the quasi-orthogonality between the reshuffled backscatter signal and the direct-link component, the proposed receiver effectively mitigates DLI and enables reliable detection without requiring dedicated spectral resources, or instantaneous Backscatter-Link (BL) Channel State Information (CSI). Analytical and simulation results demonstrate that Shuf-Scatter achieves superior Bit Error Rate (BER) performance under strong DLI while preserving the integrity of the legacy OFDM transmission.

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Salim Chabani, Riadh Ouzane, Salah Eddine Zegrar, Huseyin Arslan. 2026-10-13. Shuf-Scatter: Permutation-Based DLI Suppression for OFDM Ambient Backscatter. https://arxiv.org/abs/2610.17828

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