Abstract: The traditional algorithm of GNSS orientation using LAMBDA for single frequency receiver，can’t estimate the integer ambiguity in a little time，sometimes，can’t find the exact value.Based on the theory of rough integer mapping，a new algorithm for the estimation of integer ambiguity is presented to solve the problems.Searching algorithm with granularity changing can improve the searching efficiency of the integer ambiguity，and can deal with the problem of the GNSS carrier phase measurement in real time.

Key words: Global Navigation Satellites System（GNSS）, integer ambiguity, rough integer mapping, granularity changing

摘要： LAMBDA方法应用于GNSS单频单点载波相位定位时，其整周模糊度的搜索域过大，解算速度过慢，制约了单频单点精确定位技术的应用。针对这一问题，结合粗糙整数映射理论，提出变粒度搜索算法，通过改善整周模糊度搜索区域的拓扑结构，并采用有粒度的粗糙整数作为搜索单元，可有效提高搜索效率。仿真结果表明，基本实现了单频单点载波相位准实时定位。

关键词: 全球导航卫星系统（GNSS）, 整周模糊度, 粗糙整数映射, 变粒度搜索