专用短程通信辅助的车辆卫星定位故障检测方法

为了确保卫星定位性能满足特定协作式智能交通应用需求，提高车辆定位系统的故障容错能力，针对车辆卫星定位的自主故障检测与性能优化问题，提出基于专用短程通信辅助的卫星定位故障检测方法，充分利用专用短程通信设备的测距率观测信息，实现故障检测对不同类型卫星可视条件的有效适应。基于专用短程通信多普勒观测特性，构建基于载波频偏的车间测距率观测模型；设计卫星定位与专用短程通信组合观测与解算框架；基于容积卡尔曼滤波提出适于非线性观测特征的故障检测、识别与排除算法，并叠加量测噪声方差矩阵动态调整策略，对故障检测性能进行优化；基于实测试验检验车间测距率的观测性能，并运用实车轨迹对多车协同运行及定位采集过程进行仿真，检验所提出方法的故障检测性能。研究结果表明：提出的方法有效解决了常规接收机自主完好性监测算法受卫星可视条件限制的问题，所引入的量测噪声方差矩阵调整策略提升了故障检测及故障排除性能的稳定性，在给定仿真场景中，常规卫星观测条件下阶跃故障、斜坡故障排除率相对常规方法最高可分别提升52%、18%，受限观测条件下不同水平2类故障的排除率最高分别可达100%、89%，边界观测条件下不同水平2类故障的检测率最高分别可达100%、96%。研究结果对于充分发挥车-车协同模式的核心优势、保障车辆定位性能具有重要价值。

Dedicated Short-range-communication-aided Fault Detection Method for Satellite-based Vehicle Positioning

To meet the requirements of specific cooperative intelligent transportation system applications and improve the fault tolerance capabilities of vehicle positioning based on the Global Navigation Satellite System (GNSS), this study aimed to develop an autonomous fault detection method for satellite-based vehicle positioning and optimize its performance. Dedicated Short-range Communication (DSRC)-aided fault detection for satellite positioning was realized through the effective utilization of vehicle-to-vehicle range rate measurements. This allows adaptive fault detection under different satellite observation conditions. Firstly, a vehicle-to-vehicle range rate measurement model was established based on carrier frequency offsets derived from Doppler measurements through DSRC. Secondly, a GNSS/DSRC integrated framework was constructed for measurement updating and position computation. Based on this framework, a fault detection, identification, and exclusion method was developed using the nonlinear cubature Kalman filter. An adaptive tuning strategy for the measurement noise variance matrix was introduced to enhance fault detection capabilities. Finally, a field test was performed to verify the precision of DSRC-based range rate measurement. Simulations of vehicular cooperation and GNSS/DSRC data collection were conducted to validate the performance of fault detection and exclusion using the proposed method. The results demonstrate that the proposed method overcomes the constraint of satellite visibility using a conventional Autonomous Receiver Integrity Monitoring (RAIM) solution. The adopted parameter tuning strategy improves the stability of fault detection and exclusion under different fault scenarios. Under the target simulation scenario, the improvements in fault exclusion rates for step and ramp faults under the normal satellite observation condition can be as high as 52% and 18%, respectively, compared to the conventional RAIM method. Under the constrained GNSS observation condition, the exclusion rates for these two fault types at different levels can reach 100% and 89%, respectively. Under the critical observation condition, the fault detection rates for these fault types can be as high as 100% and 96%, respectively. These results demonstrate the advantages of guaranteeing the performance of vehicle positioning by taking advantage of the vehicle-to-vehicle cooperation mode.