电离层残差辅助北斗三频伪距载波相位组合周跳探测

提出一种基于单差模型的电离层残差辅助伪距相位组合周跳探测方法。基于北斗三频实测数据,以波长、电离层延迟系数与噪声为约束条件,优化选取3个线性无关的超宽巷(EWL)、宽巷(WL)组合(0,-1,1)、(1,4,-5)、(4,-2,-3),并利用伪距相位组合法进行周跳的探测与修复。实验结果表明,这3个组合甚至可以实时探测出原始频点上1周的小周跳。针对三频伪距相位组合周跳探测法可能出现的误探情况,提出利用电离层残差法辅助三频伪距相位组合周跳探测的方法,即首先利用原始观测量求出历元间电离层残差,再将相邻历元间所求的历元间电离层残差二次作差。实验表明,该方法可以实时准确地探测与修复不同基线下单差的各类大小周跳。

Cycle Slip Detection with Code-Phase Combination and Ionospheric Residual Error

With BDS real data, three linearly independent combinations of extra-wide lane (0, 1, -1), (1, 4, -5) and sub-extra-wide lane (4,-2,-3) are chosen based on triple-frequency theory with the constraints of wavelength, factor of ionospheric delay and noise, and then the code-phase combination algorithm is adopted to detect and correct cycle slip. Experimental results show that the three combinations can even detect one small slip. Considering the probability of detecting a wrong slip, the ionospheric residual error method is proposed to assist in detection. That is, original observations are used to calculate the ionospheric residual error, followed by difference of the ionospheric residual delay between adjacent epochs. The results validate that the algorithm can detect and correct all kinds of single-differenced cycle slip in real time.