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arXiv · 2603.17935

Overlap-Summation-Based Pulse Shaping Transceiver for Affine Frequency Division Multiplexing

Haojian Zhang·Jiayan Yang·Tingting Zhang·Xu Zhu·Qinyu Zhang
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Abstract

Affine frequency division multiplexing (AFDM) has recently emerged as a promising waveform for doubly-selective channels. A direct-windowing-based pulse shaping transceiver (PS-AFDM) was proposed to suppress the Doppler sidelobes, thus improving the accuracy of channel estimation. We observe that the legacy PS-AFDM significantly increases the condition number of the effective channel matrix when path delay and Doppler parameters are randomly distributed, such ill-conditioning leads to the degradation in the solution stability of channel equalization under noisy conditions, thus resulting in the degradation of bit error rate (BER). To address this issue, this letter applies the existing weighted overlap-summation (WOLA) transceiver to AFDM and proposes a novel channel-aware (CA) receive shaping window design, which simultaneously achieves accurate channel estimation and robust equalization performance, at the cost of time-domain prefix and receive window calculation overheads. The resulting scheme is termed CAWOLA-AFDM. Compared with the legacy WOLA scheme, which employs a fixed receive window, the proposed CAWOLA design exploits the non-instantaneous channel estimates of power gains and Doppler shifts to design a channel-tailored and closed-form receive shaping window, thereby further enhancing channel estimation accuracy while maintaining the channel condition number when a Nyquist prototype window is adopted. The proposed CAWOLA receive window design aims to provide the effective AFDM channel with a more compact DAFT-domain support. The source codes for the simulations are provided at https://github.com/SANIS-HITSZ/Waveform_AFDM.

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Haojian Zhang, Jiayan Yang, Tingting Zhang, Xu Zhu, Qinyu Zhang. 2026-03-18. Overlap-Summation-Based Pulse Shaping Transceiver for Affine Frequency Division Multiplexing. https://arxiv.org/abs/2603.17935

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