AI 中文总结
本文分析AFDM系统在双选择性衰落信道下IQ不平衡对信号检测的影响，发现其引入镜像干扰导致性能下降，尤其高阶QAM，需补偿或感知算法保障稳健运行。
AI 中文摘要
本文研究了在双选择性瑞利衰落信道上，仿射频分复用（AFDM）系统中同相/正交（IQ）不平衡对信号检测的影响。评估了AFDM在不同IQ失配条件下的误码率（BER）性能，并与理想收发机进行了比较。仿真结果表明，在理想条件下，BER随着信噪比（SNR）的增加而迅速降低。然而，IQ不平衡引入了在仿射域中扩散的镜像干扰，导致显著的性能下降。结果进一步强调了实际IQ不平衡对AFDM系统在不同正交幅度调制（QAM）阶数、信道场景以及与正交频分复用（OFDM）和正交时频空间（OTFS）系统比较中的影响。特别是，高阶QAM性能显著下降，表明需要IQ不平衡补偿技术或感知损伤的检测算法，以确保实际AFDM系统的稳健运行。
英文摘要
This paper investigates the impact of in-phase/quadrature (IQ) imbalance on signal detection in affine frequency-division multiplexing (AFDM) systems over doubly dispersive Rayleigh fading channels. The bit error rate (BER) performance of AFDM under various IQ mismatch conditions is evaluated and compared with that of an ideal transceiver. Simulation results show that, under ideal conditions, BER decreases rapidly with increasing signal-to-noise ratio (SNR). However, IQ imbalance introduces image interference that spreads across the affine domain, causing significant performance degradation. The results further highlight the impact of practical IQ imbalance on AFDM systems across different quadrature amplitude modulation (QAM) orders, channel scenarios, and comparisons with orthogonal frequency-division multiplexing (OFDM) and orthogonal time frequency space (OTFS) systems. In particular, higher-order QAM performance degrades significantly, indicating the need for IQ imbalance compensation techniques or impairment-aware detection algorithms to ensure robust operation in practical AFDM systems.
