A.衛(wèi)星鐘差B.接收機(jī)鐘差C.星歷誤差D.電離層折射
A.第一數(shù)據(jù)模塊B.第二數(shù)據(jù)數(shù)據(jù)C.第三數(shù)據(jù)模塊D.第四數(shù)據(jù)模塊