欺骗干扰对GNSS/INS系统定位性能的影响

Influence analysis of spoofing interference on positioning performance of GNSS/INS system

全球卫星导航系统(GNSS)/惯性导航系统(INS)的组合导航系统中,GNSS模块易受欺骗干扰的影响,通过开展欺骗干扰对GNSS/INS系统定位性能的影响分析,有助于发掘潜在的GNSS/INS组合系统欺骗干扰检测和抑制方法。将欺骗干扰分为阶跃式位置欺骗、斜坡式位置欺骗、阶跃式速度欺骗和斜坡式速度欺骗四类,根据相应类型的特点建立了欺骗干扰模型,基于该模型理论推导了欺骗干扰影响下位置偏差和速度偏差的变化规律:阶跃式位置欺骗产生阶跃的位置偏差和脉冲的速度偏差;斜坡式位置欺骗产生呈比例变化的位置偏差和阶跃的速度偏差;阶跃式速度欺骗产生阶跃变化的位置和速度偏差;斜坡式速度欺骗产生呈比例变化的位置和速度偏差。仿真结果表明,四类欺骗干扰对应的位置和速度偏差与理论分析一致,通过调整观测噪声矩阵中伪距测量噪声标准差,位置偏差最高减少了34.5%,速度偏差减少了99.5%,有效降低欺骗干扰对位置速度影响的程度。

Global Navigation Satellite system(GNSS)/Inertial Navigation System(INS)integrated navigation system is susceptible to spoofing interference because of the GNSS module.By analyzing the impact assessment of spoofing interference on position performance of GNSS/INS system,it is helpful to explore potential spoofing detection and suppression methods for GNSS/INS system.In this paper,spoofing interference is divided into four types:step position spoofing,ramp position spoofing,step velocity spoofing and ramp velocity spoofing.According to the characteristics of each type,the spoofing interference model is established.Based on the model,the impact assessment of spoofing interference on GNSS/INS system’s position and velocity offset are analyzed:Step position spoofing produces step position offset and pulsing velocity offset.Ramp position spoofing produces proportional position offset and step velocity offset.Step velocity spoofing produces position offset and velocity offset with step changes.Ramp velocity spoofing produces position offset and velocity offset with proportional changes.The simulation results show that the position and velocity offset caused by spoofing interference are consistent with the theoretical analysis.By adjusting the standard deviation of pseudo-range measurement noise in the observation noise matrix,the position offset is reduced by 34.5%and the velocity offset is reduced by 99.5%,which effectively reduces the impact of spoofing on position and velocity.