Abstract: In Galileo Navigation Satellite System,Binary Offset Carrier（BOC） modulation is a new technology that is different from GPS and GLONASS.This paper has analyzed BOC modulation in several aspects like subcarrier waveform,power spectral density and autocorrelation function and so on.Difference of cosine subcarrier signal from sine subcarrier signal can be seen from the analysis.Multipatherror has been given in the last part as the simulation result about BOC（1,1） and BOC（1.5,1）.The results show that if the subcarrier is cosine type,antimultipatherror performance of BOC signal is better than that of BOC signal when the subcarrier is sine type.

Key words: satellite navigation, BOC modulation, multipatherror

摘要： 论文针对伽利略卫星导航信号相对于传统卫星导航信号的不同,论述了该系统中采用的BOC调制技术和BOC调制信号的一些基本特性,提出应采用余弦副载波类型的BOC信号,并在此基础上对BOC信号的多径误差进行仿真验证。仿真结果表明,余弦副载波类型的BOC（1,1）和BOC（1.5,1）的抗多径能力要优于相同参数的正弦副载波类型BOC信号。

关键词: 卫星导航, BOC调制, 多径误差