无人机载低成本北斗/GPS实时定位精度分析

Real-Time Positioning Accuracy Analysis Using Low-Cost BDS/GPS Equipped on Unmanned Aerial Vehicles

北斗卫星导航系统采用3种轨道类型卫星组成的混合星座,抗遮挡能力强,同时创新融合导航与通信能力,具备全球定位、导航、授时服务能力。利用小型无人机搭载低成本北斗/GPS芯片,设计并实现软硬件系统。通过实时回传的观测数据,采用GPS、北斗以及北斗/GPS组合三种定位模式,进行实时单点定位,并对各模式下的可见卫星数、空间几何精度衰减因子和定位精度进行分析与评估。实验表明:无人机载北斗/GPS组合定位,平均PDOP值为1.4,可见卫星数达32,实现了较优的观测几何构型,历元利用率高。北斗/GPS组合模式与RTK接收机获取的坐标比较,在E、N、U方向上定位偏差分别达到2.5m、4.1m和2.4m。

The BciDou navigation satellite system(BDS)employs a hybrid constellation consisting of three types of orbit satellites,enabling robust anti—obstruction capabilities and providing positioning,navigation,and timing services for global users.Software and hardware systems were designed and implemented for BDS/GPS standard point positioning using small unmanned aerial vehicles equipped with cost—effective BDS/GPS chips.By transmitting real—time positioning data,the system utilizes three modes:GPS,BDS,and BDS/GPS combination.Analysis and evaluation were conducted to compare visible satellite numbers,position dilution of precision(PDOP),and positioning accuracy across each mode.The experiment demonstrated that the unmanned aerial vehicle using BDS/GPS combined positioning achieved an average PDOP value of 1.1,with 32 visible satellites,achieving an optimal observational geometric configuration and high epoch utilization.When comparing the BDS/GPS combination mode with coordinates obtained by an RTK receiver,positioning deviations reached 2.5 m,4.1 m,and 2.4 m in the cast,north,and up components,respectively.