针对实际试验过程中在轨运行卫星资源限制问题, 该文提出采用无人机等效模拟卫星部分功能开展试验测试, 并围绕无人机飞行航迹与卫星轨迹在干扰站视角下的等效性、无人机与卫星在成像观测试验中的差异程度和合成孔径雷达干扰设备辐射波在无人机位置电磁辐射强度的等效性3个核心问题展开了分析与计算。研究结果表明：优化后的无人机飞行轨迹使无人机能以恒定或分段可变速度沿预设航线飞行, 在小区域仿真中, 该轨迹与卫星轨迹相比, 展现出较高保真度和可靠性; 无人机影像与卫星参考数据之间的灰度均方根误差始终低于5%, 成像观测差异较小; 配备光学和SAR传感器的旋翼无人机沿预设轨迹飞行时, 可有效模拟卫星的观测和干扰行为。该文通过系统分析无人机模拟卫星观测的等效程度, 验证了在特定条件下, 无人机模拟卫星实施观测方案的可行性。该文研究结果可为后续新型探测和识别载荷在轨等效观测试验验证方式提供参考。

Objective: With the rapid proliferation of spacecraft, on-orbit satellite resources have become highly congested, resulting in increasingly scarce and non-repeatable experimental windows. This bottleneck severely impedes the iterative validation of emerging optical payloads, synthetic aperture radar (SAR) architectures, and interference countermeasure technologies. To address this challenge, this paper proposes the use of an unmanned aerial vehicle (UAV) system as a controllable and functionally equivalent surrogate for a satellite. By developing a high-fidelity UAV trajectory emulation framework, the study systematically evaluates the UAV's substitutability in three representative mission scenarios (optical imaging, SAR imaging, and SAR jamming), thus providing a low-cost, repeatable, and risk-controllable ground-air integrated validation pathway for future satellite experiments and enabling a rapid-prototyping technology loop for forthcoming space missions. Methods: The proposed methodology comprises the following components: (1) Trajectory feasibility analysis: a straight-line emulated trajectory, combined with a piecewise constant velocity flight pattern, is configured to simulate a satellite orbit. Simulation results are used to optimize the UAV's flight path for improved fidelity and reliability. (2) UAV-based satellite trajectory planning: the two-line element (TLE) set of the target satellite is parsed to obtain orbital parameters. The satellite's azimuth-elevation profile relative to a ground-based jammer is derived and converted using an angle-equivalent mapping function into a sequence of UAV waypoints. This mapping accounts for airspace constraints, yielding a practical waypoint-generation protocol. (3) Joint imaging-jamming experiment: the UAV is equipped with optical and SAR payloads to measure discrepancies between its imagery and satellite benchmarks. Simultaneously, the electromagnetic field intensity of SAR jamming signals at the UAV location is assessed to validate equivalence. Results: The optimized UAV trajectory enabled the aircraft to follow predefined routes with constant or piecewise variable speeds. The entry-point timing deviations remained within 2 s, and waypoint position errors stayed below 5.00 m, ensuring consistent alignment within the jammer-to-satellite antenna beam. This demonstrated the system's viability for small-area emulation with high fidelity and reliability. The experimental analysis confirmed that UAV-based satellite observation was technically feasible. The grayscale root-mean-square error between UAV imagery and satellite references remained below 5%, supporting the effectiveness of the emulation strategy. Conclusions: In the absence of an operational satellite, a rotary-wing UAV equipped with optical and SAR sensors can emulate a satellite's observational and jamming behavior when flown along a predefined trajectory. The piecewise constant velocity flight pattern allows the UAV to remain aligned along the satellite-target axis, with temporal deviations kept within acceptable limits despite minor speed variations. Following flight control optimization and electromagnetic hardening, the UAV-based emulation platform proves feasible for real-world deployment. Within a restricted operational zone, the UAVs onboard generate spatially resolved data comparable to satellite outputs. Moreover, a co-tracking jammer can effectively intercept SAR signals at the UAV location, thereby achieving an equivalent satellite observation scenario to a significant extent.