一种基于VDFLL和CaKFPLL的INS/GNSS超紧耦合方法

摘要

为了提高复杂电磁环境下的GNSS抗干扰能力，针对低成本制导武器的导航需求特点，提出了一种基于矢量延迟锁定环和锁频环并级联卡尔曼滤波锁相环的INS/GNSS超紧耦合的改进算法。分析了 INS 辅助矢量跟踪结构，给出了基于鉴别器的低复杂度基带预处理滤波器和基于 EKF 锁相环滤波器的详细设计方法。此外，设计了干扰环境下的高动态飞行轨迹，用于验证INS/GNSS超紧耦合算法，动态仿真试验结果表明，在干扰环境下INS/GNSS超紧耦合系统的导航能力相对于独立式高动态跟踪技术的接收机有明显优势，跟踪GPS L1 C/A情况下，可容忍干信比为48.6 dB，比独立式接收机的干扰抑制能力提高了约12 dB。%In order to improve GNSS’s anti-jamming ability under complex electromagnetic environment, an improved algorithm of INS/GNSS ultra-tight coupling(UTC) based on vector DLL(delay locked loop) and FLL(frequency locked loop) as well as cascade loop filter of phase-locked loop is proposed for low cost guided weapon navigation. The architecture of INS-aided GNSS vector tracking is analyzed, a discriminator-based pre-processing filter for vector tracking is devised to reduce the computational complexity, and an extended Kalman filter for PLL is given. A ballistic trajectory under jamming condition is also designed to test the UTC algorithm. Dynamic simulation test shows that the performance of UTC is better than that of stand-alone high dynamic tracking under interference environment. The UTC can lock GPS L1 C/A signal at J/S level of 48.6 dB which is about 12 dB bigger than stand-alone receiver.