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arXiv · 2603.26143

Optimized Non-Uniform Pilot Pattern for OFDM Sensing

Amir Bouziane·Huseyin Arslan
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Abstract

Standard periodic pilot patterns in orthogonal frequency division multiplexing (OFDM) systems induce severe delay-domain grating lobes, compromising radar sensing. This paper proposes a two-stage framework to design non-periodic pilot patterns that minimize the peak sidelobe level (PSL) while strictly enforcing communication anchor constraints. We black solve this combinatorial problem using a low-complexity hybrid greedy-stochastic cyclic coordinate descent (SCCD) algorithm. This approach shatters cyclic periodicities to suppress deterministic grating lobes beneath the impassable data-to-pilot interference (DPI) noise floor. System-level evaluations demonstrate the performance of the proposed design in resolving the sensing-communication trade-off, showing improved range root mean square error (RMSE) without degrading the primary communication bit error rate (BER).

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Amir Bouziane, Huseyin Arslan. 2026-03-27. Optimized Non-Uniform Pilot Pattern for OFDM Sensing. https://arxiv.org/abs/2603.26143

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