适用于单频GPS用户的周跳探测方法

摘要

针对单频GPS（Global Position System）用户的载波相位周跳探测问题,在传统的载波相位和伪距组合方法的基础上提出了一种新的周跳探测方法.该方法将载波相位和码伪距的组合观测量在历元间做差形成差分序列,以此构造实时的周跳探测量,由于该探测量易受观测噪声的影响,因此使用仰角指数模型作为经验模型对于测距噪声进行估计,基于假设检验的方法,通过对该探测量是否超过相应的检测门限来判断是否存在周跳.在实测的GPS观测数据基础上,对这一方法进行了验证,结果表明：相对于传统的周跳探测方法,该方法可以更加及时、准确地发现较小的周跳,对于单频的GPS用户具有较好的适应性.%Aiming at the detection of the cycle slips in the carrier phase measurements for the single-frequency global pesition system（GPS） users,a novel algorithm was proposed based on the conventional method with the combination of the pseudo range and the carrier phase.The pseudo range and the carrier phase were differentiated between the adjacent epochs and a related detection sequence could be constructed.The real-time estimation of the variance for the detection sequence was accomplished with the elevation exponential model as the conventional method was susceptible to the measurement noise.Finally,a detection variable was formed and the existence of the cycle slips were judged by the comparison between the detection variable and the threshold which is deduced from the hypothetic check theory.The algorithm was verified by the real GPS measurements and the results indicate that the small cycle slips can be detected with the algorithm timely.Moreover,the algorithm is available for the single-frequency GPS users.