This paper proposes an anti-interference affine frequency division multiplexing (AFDM) system to ensure reliability and resource efficiency under malicious high-power interference originating from adversarial devices in high-mobility scenarios. Closed-form expressions of interferences in the discrete affine Fourier transform (DAFT) domain are derived by utilizing the stationary phase principle and the Affine Fourier transform convolution theorem, which indicates that interference impacts can be classified into stationary and non-stationary categories. On this basis, we reveal the analytical relationship between packet throughput and the paramerters of spread spectrum and error correction coding in our proposed anti-interference system, which enables the design of a parameter optimization algorithm that maximizes packet throughput. For reception, by jointly utilizing the autocorrelation function of spreading sequence and the cyclic-shift property of AFDM input-output relation, we design a linear-complexity correlation-based DAFT domain detector (CDD) capable of achieving full diversity gain, which performs correlation-based equalization to avoid matrix inversion. Numerical results validate the accuracy of the derived closed-form expressions and verify that the proposed anti-interference AFDM system could achieve high packet throughput under interference in high-mobility scenarios.

翻译：本文提出了一种抗干扰仿射频分复用系统，旨在高移动性场景下，对抗来自恶意设备的高功率干扰，确保通信的可靠性与资源效率。通过利用平稳相位原理和仿射傅里叶变换卷积定理，推导了离散仿射傅里叶变换域中干扰的闭式表达式，表明干扰影响可分为平稳与非平稳两类。在此基础上，我们揭示了所提抗干扰系统中数据包吞吐量与扩频及纠错编码参数之间的解析关系，从而设计出一种最大化数据包吞吐量的参数优化算法。在接收端，通过联合利用扩频序列的自相关函数及AFDM输入输出关系的循环移位特性，我们设计了一种基于相关性的线性复杂度DAFT域检测器，能够实现全分集增益，并采用基于相关的均衡方法以避免矩阵求逆。数值结果验证了所推导闭式表达式的准确性，并证实所提出的抗干扰AFDM系统在高移动性干扰场景下可实现较高的数据包吞吐量。