AI 中文总结
该研究针对ISAC系统HPA非线性失真问题，分析了AFBM波形的鲁棒性，推导其AF统计特性，提出低复杂度接收机，仿真表明AFBM在非线性放大下仍兼具良好感知与通信性能。
AI 中文摘要
未来感知与通信一体化（ISAC）系统严苛的能效要求面临根本性挑战。与传统通信系统不同，ISAC发射机必须辐射显著更高的功率以确保可靠的目标检测，这迫使高功率放大器（HPA）工作在接近饱和的状态，此时非线性失真不可避免。因此，必须仔细评估每种候选ISAC波形对HPA非线性的鲁棒性。在此背景下，本文研究了仿射滤波器组调制（AFBM）的鲁棒性，AFBM是一种新近提出的波形，它结合了仿射调制的延迟-多普勒鲁棒性，同时具有降低的峰均功率比（PAPR）和改善的频谱约束。我们对放大后的AFBM波形的模糊函数（AF）进行了统计表征，推导了其均值、方差和服从莱斯分布的幅度的近似表达式。此外，我们提出了一种考虑HPA非线性的低复杂度高斯信念传播接收机，用于通信检测。仿真结果验证了该分析框架，证明即使在严重的非线性放大下，AFBM仍能保持良好的感知特性和鲁棒的误码率（BER）性能。
英文摘要
The stringent energy-efficiency requirements of future Integrated Sensing and Communications (ISAC) systems are fundamentally challenged. Unlike conventional communication systems, ISAC transmitters must radiate significantly higher power to ensure reliable target detection, forcing the High-Power Amplifier (HPA) to operate closer to saturation, where nonlinear distortions become unavoidable. Consequently, the robustness of every candidate ISAC waveform to HPA nonlinearities must be carefully assessed. In this context, this paper investigates the robustness of Affine Filter Bank Modulation (AFBM), a recently proposed waveform that combines the delay-Doppler resilience of affine modulation with reduced Peak-to-Average Power Ratio (PAPR) and improved spectral containment. We develop a statistical characterization of the Ambiguity Function (AF) of the amplified AFBM waveform, deriving approximate expressions for its mean, variance, and Rician-distributed magnitude. Furthermore, a low-complexity Gaussian belief propagation receiver accounting for HPA nonlinearities is proposed for communication detection. Simulation results validate the analytical framework and demonstrate that AFBM preserves favorable sensing characteristics and robust Bit Error Rate (BER) performance even under severe nonlinear amplification.
CommentsSubmitted to IEEE Transactions on Wireless Communications
