摘要
Galileo卫星导航系统在E1频段使用CBOC(6,1,1/11)调制方式取代原计划的BOC(1,1)调制方式。介绍了CBOC(6,1,1/11)的频谱、实现方式及其相关函数,并通过仿真计算,对比分析了CBOC(6,1,1/11)和BOC(1,1)调制方式在谱分离系数、根均方带宽和多径误差包络的差别。结果表明:CBOC(6,1,1/11)和BOC(1,1)频谱相近,但增加了部分高频分量,且CBOC(6,1,1/11)不同的实现方式相关函数上有一定的差别;CBOC(6,1,1/11)在与同频段其它服务信号间的谱分离系数整体上小于BOC(1,1),降低了系统内和系统间的干扰;CBOC(6,1,1/11)根均方带宽大于BOC(1,1),减小了跟踪抖动;CBOC(6,1,1/11)的多径误差包络整体上小于BOC(1,1),提高了系统的抗多径能力。
In Galileo satellite navigation system, the original plan of BOC （1,1） modulation in E1 band was replaced by the CBOC （6, 1,1/11） modulation. This paper presents the spectrum, implementation, and autocorrelation function （ACF） of CBOC （6, 1,1/11 ）. Then according to the simulation and computing, the comparison between the CBOC（6, 1, 1/11 ） and BOC （1, 1 ） is evaluated to investigate the differences, including spectral separation factor, mot mean square （RMS） bandwidth and multipath error envelope. The results of the study indicate that the CBOC （6, 1, 1/11） and BOC （1, 1 ） spectrums are similar, but the former adds some high-fre- quency component. The CBOC（6, 1, 1/11 ） of different implementations have a few differences in the ACF. The spectral separation factors of the CBOC（6, 1, 1/11 ） with the other services which are on the same frequency band are smaller than those of BOC（ 1, 1 ） on the whole, which is beneficial to reduce the interference between the systems. The RMS bandwidth of the CBOC（6, 1, 1/11 ） is larger than that of BOC（ 1, 1）, the former reduces the tracking jitter consequently. The multipath error envelopes of CBOC（6, 1, 1/11 ） are smaller than those of BOC（ 1, 1 ） by and large,which indicates that the CBOC（6,1, 1/11 ） improves the anti-multipath capability.
出处
《电讯技术》
北大核心
2010年第7期21-25,共5页
Telecommunication Engineering
关键词
卫星导航系统
CBOC调制
相关函数
谱分离系数
根均方误差
多径误差
satellite navigation system
CBOC modulation
autocorrelation function （ACF）
spectral separation factor
mot mean square（RMS）
muhipath mitigation
