卫星导航接收机鉴相器有限字长效应研究  

Performance analysis of finite word-length effect on phase discriminator in satellite navigation receiver

作　　者：刘小汇[1] 黄龙[1] 

机构地区：[1]国防科技大学电子科学与工程学院,湖南长沙410073

出　　处：《国防科技大学学报》2013年第2期87-92,共6页Journal of National University of Defense Technology

基　　金：航天支撑基金资助项目(2011-HTGFKD)

摘　　要：卫星导航接收机跟踪信号的能力取决于锁相环的跟踪精度,相位鉴别器在锁相环设计中具有重要地位。针对点积鉴相器和二象限反正切鉴相器在输入信号有限字长效应下,对鉴相器性能的影响问题,建立了鉴相器有限字长误差模型。通过理论推导输入信号的统计特性,计算得到鉴相器输入信号均值和方差表达式,并分析了有限字长对鉴相器的均值和方差、收敛区间和鉴别增益的影响情况。由理论和仿真验证,得出了鉴相器在输入信号有效位数3比特以上时,对环路跟踪精度没有影响的结论。The ability of navigation receiver to track signals is affected by phase locked loop tracking accuracy. Phase discriminator plays an important role in the design of phase locked loop. Base on the influence on the finite word-length effect to the dot product and the arctangent discriminator＇ s performance, a word length error model was proposed. The theoretical analysis of the finite word-length affected to the discriminator＇s converge range and gain was presented by deducing the input signal＇s statistical characteristic. Analysis and simulation show that the deviation of input signals of the phase discriminator with up to 3 bits has no influence on the carrier tracking accuracy.

关 键 词：锁相环 相位鉴别器 点积鉴相器 反正切鉴相器 有限字长 

分 类 号：TN967.1[电子电信—信号与信息处理]