北斗系统信号NH码处理方法研究  

Research on NH Code Processing Method of BDS Signal

作　　者：夏长峰 刘党辉 金东阳 

机构地区：[1]装备学院,北京101416

出　　处：《导航定位学报》2014年第3期25-29,共5页Journal of Navigation and Positioning

摘　　要：北斗系统的中圆地球轨道卫星及倾斜地球同步轨道卫星信号中调制有1kbit/s的NH码。NH码的存在会造成传统的频率跟踪环路鉴别器错误输出,并且会对导航数据解码造成影响。在对上述问题分析的基础上,提出了采用二相反正切鉴别器来克服NH码跳变的影响,并利用相关法去除导航数据中的NH码后获取导航电文。最后将所提出的上述算法应用于北斗软件接收机的跟踪环路及数据解调环节,实测数据处理结果表明了算法的有效性。Medium Earth orbits （MEO） /inclined geo-synehronous orbits （IGSO） satellite signal of BeiDou satellite navigation system （BDS） is modulated by NH code with the rate of 1 kbit/s. NH code will have bad effects on conventional frequency lock loop discriminator and make it difficult to demodulate navigation message. Based on the analysis of the problems mentioned above, a two-quadrant arctangent discriminator which is insensitive to NH code transition is proposed. Removing NH code with correlation method is used to demodulate navigation data so that correct message is got. Finally, the method is used for BeiDou software receiver in tracking loop and demodulation. The result of real signal processing verified that the proposed method is effective.

关 键 词：北斗卫星导航系统 软件接收机 NH码 跟踪 解调 

分 类 号：P228[天文地球—大地测量学与测量工程]