A differential arithmetic is proposed for simplifying the observationalequation as well as for avoiding the computation of the unknown integer constant.
提出相邻历元间差分算法，大大简化了观测方程，同时避免积分常量的计算。
2
When the observationalequation is under the hypothesis on singularity and a solution of the lemma exists, we show that there exists a minimal order filter.
当量测方程奇异假设条件成立及引理有解时，本文证明了最小阶奇异滤波器必定存在。
3
The second part shows GPS observationalequation, the corresponding error sources, the characteristics of errors and the essential methods for error processing.