In the process of composing a double-differenced positioning model, it is difficult to separate different frequency signals between code division multiple access (CDMA) systems, the single-difference ambiguity of the pivot satellite and phase differential inter-system biases (PDISBs). Hence it is difficult to calibrate in advance the bias between systems in order to build an inter-system model which only needs one pivot satellite. Based on analysis of the stability of PDISB parameters for non-overlapping frequency CDMA systems, this study adopts a particle filter to estimate the fractional part of the PDISBs (F-PDISBs) between the systems and proposes a particle filter-based inter-system positioning model. Results show that the F-PDISBs and code DISBs for the baselines with the same receiver types and some with different receiver types are rather stable over time and for these baselines it is feasible to use a particle filter to estimate the F-PDISB parameters in the initial stage. Having attained the F-PDISBs, the inter-system model can be constructed to improve positioning accuracy in complex operational environments.

中文翻译：

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非重叠频码分多址系统的基于粒子滤波器的系统间定位模型

在构建双差定位模型的过程中，码分多址（CDMA）系统之间的不同频率信号难以分离，枢轴卫星的单差模糊性和相位差系统间偏差（PDISB）。因此，很难预先校准系统之间的偏差以建立一个只需要一个枢轴卫星的系统间模型。本研究在分析非重叠频率CDMA系统PDISB参数稳定性的基础上，采用粒子滤波器估计系统间PDISB（F-PDISB）的小数部分，提出了一种基于粒子滤波器的系统间定位方法。模型。结果表明，具有相同接收器类型和一些具有不同接收器类型的基线的 F-PDISB 和代码 DISB 随着时间的推移相当稳定，对于这些基线，使用粒子滤波器估计 F-PDISB 参数是可行的初期。在获得 F-PDISB 之后，可以构建系统间模型以提高复杂操作环境中的定位精度。