单项选择题
A.Parallel bearings B.Long-range bearings C.Short-range bearings D.Cross bearings
The use of pulse groups and extremely precise timing at...
单项选择题The use of pulse groups and extremely precise timing at each Loran-C station makes possible the use of（）.
A.High frequency pulses B.Combinations of high and low frequency pulses C.The same frequency for all stations in a chain D.Varied long and short pulses
The time interval between the transmission of signals f...
单项选择题The time interval between the transmission of signals from a pair of Loran-C stations is very closely controlled and operates with（）.
A.An atomic time standard B.Daylight Savings Time C.Eastern Standard Time D.Greenwich Mean Time
The receiver uses（）satellites to compute latitude，longi...
单项选择题The receiver uses（）satellites to compute latitude，longitude，altitude，and velocity．
A.one B.two C.three D.four
