To address the issue of metallic objects around a balise affecting its electromagnetic transmission performance,a balise antenna model is established in electromagnetic simulation software. The simulation experiments are carried out by varying three parameters:the metal surface area,the vertical distance between the metal surface and the balise,and the metal surface thickness. The uplink signal amplitude curves of the balise under different parameters are obtained,and the transmission performance metrics are calculated to analyze the impact. Results show that: a larger metal surface area leads to lower performance metrics,such as a reduced number of safety message frames received by the balise transmission module (BTM),with a more significant degradation and greater interference from the sidelobe region. When the metal area is greater than 320 mm×320 mm,the uplink field strength consistency requirement can no longer be met. A greater absolute distance between the metal surface and the balise results in less interference from the sidelobe region,and the distance must be greater than 123 mm to satisfy the field strength consistency requirement. Increased metal surface thickness causes greater interference from the sidelobe region,and the thickness should not exceed 1 mm.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |