# Low-Altitude Sensing Model: Analysis Leveraging ISAC in Real-World Environments
## 4 Performance Verification and Analysis
### Single Base Station Sensing Validation  
Single base station sensing tests were conducted in the real-world scenario test environment. Through multi-altitude, multi-directional flight tests, the effectiveness of the single base station 3D sensing model in real-world scenarios was verified, highlighting its advantages and shortcomings and providing a basis for model optimization and practical deployment. We aimed to verify the practical ability of the single base station 3D sensing model to replicate sensing characteristics in real-world environments. To this end, a single base station sensing test was conducted with only the sector in one direction of Site 3 activated. The antenna of this station was at a height of 30 m, and the normal direction of the antenna is shown in Figure 12.  
Figure 11: Single base station real-world scenario test environment. When analyzing the results in the horizontal direction, it is necessary to clarify the differences between the radial and horizontal directions. The radial direction refers to the straight-line direction from the antenna center to the target, where changes in the distance directly reflect the proximity of the target to the antenna. On the other hand, the horizontal direction focuses on the positional changes of the target in the horizontal cross-sectional plane relative to the antenna, emphasizing azimuthal information within the UAV. In the flights at the base station height, the nearest sensing distance in the horizontal direction deviated from the theoretical expectation by 4.5 m. Analysis shows that this deviation was not caused by the model or measurement errors but rather by the limitations of the actual test conditions. During the UAV flight tests, safety considerations prevented the UAV from taking off immediately adjacent to the antenna, requiring a certain safety distance to be maintained. This prevented setting the test starting point at the theoretical 0 m position. In the horizontal direction, this safety distance resulted in a deviation between the actual starting point and the theoretical value. In the radial direction, it manifested as the flight starting radial distance being larger than the theoretical starting distance. Therefore, this deviation was caused by the difference between the actual test environment and the ideal conditions rather than by the model. The measured data within the constraints of the safety distance reasonably reflected the sensing capabilities of the single base station, which aligned with the expectations from the perspective of the actual test logic. In the tests involving horizontal flight along the normal direction (3 OA paths), the farthest distances in both the radial and horizontal directions exceeded the theoretical values. The deviations ranged from 32.9 to 51.4 m across different heights, averaging 4.5% above the theoretical values. In the radial direction, the hardware design of the base station typically set the sensing range slightly larger than the theoretical value to mitigate coverage blind spots in complex environments, which increased the actual sensing farthest radial distance. Additionally, hardware limitations and factors such as beam fluctuations affected signal propagation, leading to deviations between the actual farthest radial distance and the theoretical value. In the horizontal direction, when the target was at the farthest distance, its positional deviation was also influenced by these factors. As the target radial distance changed, horizontal positioning changed. For the nearest distances in horizontal flight along the normal direction, both the radial and horizontal distances were slightly smaller than the theoretical values, with deviations ranging from 8.0 to 29.7 m across different heights, averaging 8.0% below the theoretical