The impact of hardware impairments on the spectral efficiency of communication systems is well studied, but their effect on sensing performance remains unexplored. In this paper, we analyze the influence of hardware impairments on integrated sensing and communication (ISAC) systems in cluttered environments. We derive the sensing signal-to-clutter-plus-noise ratio (SCNR) and show that hardware distortions significantly degrade sensing performance by enhancing clutter-induced noise, which masks target echoes. The isotropic nature of transmit distortion due to multiple stream transmission further complicates clutter suppression. To address this, we propose a distortion- and clutter-aware precoding strategy that minimizes the deviation from the communication-optimized precoder while improving sensing robustness. We also propose an alternative power allocation-based approach that reduces computational complexity. Numerical results confirm the effectiveness of the proposed approaches in overcoming hardware- and clutter-induced limitations, demonstrating significant performance gains over distortion-unaware designs.

翻译：硬件损伤对通信系统频谱效率的影响已有深入研究，但其对感知性能的影响尚未得到探索。本文分析了杂波环境下硬件损伤对集成感知与通信（ISAC）系统的影响。我们推导了感知信杂噪比（SCNR），并证明硬件失真通过增强杂波引起的噪声显著降低感知性能，从而掩盖目标回波。多流传输导致的发射失真各向同性特性进一步增加了杂波抑制的复杂性。为此，我们提出一种失真与杂波感知的预编码策略，在提升感知鲁棒性的同时最小化与通信优化预编码器的偏差。我们还提出一种基于功率分配的替代方案以降低计算复杂度。数值结果验证了所提方法在克服硬件与杂波引起的限制方面的有效性，相较于未考虑失真的设计方案展现出显著的性能提升。