基于粒子滤波地形导航算法的精确近地告警方法

Accurate ground proximity warning method based on particle filter terrain navigation algorithm

近地告警系统利用导航设备提供的位置信息在机载数字高程模型(DEM)内对航空器周边区域进行搜索,在接近地面时给出告警信息,避免航空器与地面相撞,能够有效提高飞行安全。由于航空器位置和DEM都存在误差,航空器与DEM中地形相对位置和航空器与真实地形相对位置并不完全一致,从而增加虚警和漏警。为了减少虚警和漏警,在不增加和改善导航设备的情况下,提出利用粒子滤波地形导航算法得到航空器在DEM中与地形的准确相对位置,利用该相对位置做近地告警计算。经过实际地形数据飞行仿真实验,结果表明能够有效提高近地告警的精确度和有效性,有较强的实用价值。

The ground proximity warning system can search the area around aircraft＇s current position in Digital Elevation Model（DEM）, and give out alarm information when the aircraft flies too close to the ground. It can keep the aircraft from colliding into ground and improve its flight safety. Whereas, the relative position of aircraft in DEM is not the same as in terrain due to the aircraft position error and the DEM error, which results in false or missing alarm. In order to promote the accuracy of this warning system, this paper proposes an innovative method using particle filter terrain navigation algorithm to calculate the relative position which can be used in ground proximity warning system, without a need to improve equipment performance. Flight simulation results indicate that the method can effectively improve the accuracy and effectiveness of proximity warning, and shows great value in use.