标题： 在位置不确定性下的低轨卫星干扰抑制的零点整形 显示英文标题

标题： Null-Shaping for Interference Mitigation in LEO Satellites Under Location Uncertainty

摘要： 射频干扰（RFI）对卫星通信构成了日益严峻的挑战，特别是在低地球轨道（LEO）系统的上行链路信道中，这是由于频谱拥挤程度的增加以及地面干扰源位置的不确定性。 本文研究了RFI源位置不确定性对基于波束成形的干扰抑制的影响。 首先，我们从理论上分析了RFI位置的地理不确定性如何转化为从卫星观测到的角度偏差。 在此基础上，我们提出了一种鲁棒的零点成形框架，通过随机优化将RFI位置不确定性的概率密度函数（PDF）纳入波束成形设计，从而提高通信链路的弹性。 这使得天线阵列的零点模式能够自适应地调整，以在不确定性下增强干扰抑制效果。 大量的蒙特卡洛仿真，结合了现实的卫星轨道动力学和各种RFI场景，表明所提出的方法相比传统的确定性设计显著提高了干扰抑制性能。 显示英文摘要

摘要： Radio frequency interference (RFI) poses a growing challenge to satellite communications, particularly in uplink channels of Low Earth Orbit (LEO) systems, due to increasing spectrum congestion and uncertainty in the location of terrestrial interferers. This paper addresses the impact of RFI source position uncertainty on beamforming-based interference mitigation. First, we analytically characterize how geographic uncertainty in RFI location translates into angular deviation as observed from the satellite. Building on this, we propose a robust null-shaping framework to increase resilience in the communication links by incorporating the probability density function (PDF) of the RFI location uncertainty into the beamforming design via stochastic optimization. This allows adaptive shaping of the antenna array's nulling pattern to enhance interference suppression under uncertainty. Extensive Monte Carlo simulations, incorporating realistic satellite orbital dynamics and various RFI scenarios, demonstrate that the proposed approach achieves significantly improved mitigation performance compared to conventional deterministic designs.