低轨（LEO）卫星系统具有覆盖范围广、连接数量多等优势，但同时也面临通信被侦听和干扰的安全风险。本文研究了一种面向Massive MIMO通感一体化的低轨卫星隐蔽通信技术。首先建立了卫星通信信道和雷达感知信道模型，并推导了系统的隐蔽性约束条件。在此基础上，构建了以多用户隐蔽通信速率总和最大化为目标的联合优化问题，约束条件包括雷达感知性能下限、隐蔽性要求以及卫星与雷达发射功率上限。针对该非凸优化问题，设计了交替优化框架，并结合下界最大化（MM）算法进行迭代求解。仿真结果表明，当雷达发射功率为80 W时，所提方案的系统隐蔽通信速率总和较基准方案提升约80%。与无通感一体化的低轨卫星隐蔽通信系统相比，所提方法能够利用雷达信号对监听者形成友好干扰，从而同时提升系统的隐蔽速率与通信隐蔽性。

Low Earth Orbit (LEO) satellite systems offer advantages such as wide coverage and massive connectivity but also face significant security risks from eavesdropping and interference. This paper investigates a covert communication technology for LEO satellites based on Massive MIMO Integrated Sensing and Communication (ISAC). A comprehensive system model is first established, including both the satellite communication channel and the radar sensing channel, followed by the derivation of the system’s covertness constraint. On this basis, a joint optimization problem is formulated to maximize the total multi-user covert communication rate, subject to constraints on radar sensing performance, covertness requirement, and transmit power limits of the satellite and radar. To tackle the resulting non-convex problem, an alternating optimization framework combined with the Minorize Maximization (MM) algorithm is developed to iteratively obtain a locally optimal solution. Simulation results demonstrate that when the radar transmit power is 80 W, the proposed scheme achieves approximately 80% improvement in the total covert communication rate compared to the benchmark. Compared with conventional LEO covert communication systems without ISAC, the proposed method effectively exploits radar signals to generate friendly interference against the eavesdropper, thereby enhancing both the covert transmission rate and communication covertness simultaneously.