基于改进Hatch滤波的BDS多基准一致性检测

Multi-reference Consistency Check for BDS Based on Improved Hatch Filter

多路径效应对伪距测量的影响一直是制约卫星系统完好性监测的重要因素,相位平滑伪距算法可以有效抑制多路径对伪距测量的影响。针对北斗卫星系统伪距测量易受多路径影响的特点,提出一种改进的Hatch滤波算法。基于输出方差最小原则,建立起滤波器参数θ与输出伪距方差的关系表达式,通过对方差表达式求导,选取了新的滤波器参数。实验证明,改进的Hatch滤波提高了伪距测量精度,减小了B值的偏差和波动范围,提高了北斗卫星系统多基准一致性检测的能力。

The influence of multipath effect on pseudo-range measurement is always an important constraint for integrity monitoring of satellite system, and carrier phase smoothing code pseudo-range method can restrain the influence effectively. Considering that the pseudo-range measurement of BeiDou System （BDS） is easily affected by the muhipath effect, we proposed an improved Hatch filter to solve the problem. The relational expression of the filter parameter θ with pseudo-range variance was established, and the new filter parameter was selected based on principle of minimum variance. The results show that the new method can improve the precision of pseudo-range measurement, and decrease the bias and fluctuation range of B-value. This method can improve the capability of muhi-reference consistency check.