接收卫星超高频信标发出的多卜勒信号来进行测轨和定位(导航)用的地面接收机,一般要对电离层的一阶折射效应进行修正,才能获得较高的精度。一台接收机接收到的频率f_R与卫星信标频率f_s之差即为多卜勒频率(移),对超高频来说 Terrestrial receivers that receive Doppler signals from satellite UHF beacons for rail and positioning (navigation) generally correct the first-order refraction effect of the ionosphere to achieve high accuracy. The difference between the frequency f_R received by a receiver and the satellite beacon frequency f_s is the Doppler frequency (shift). For a UHF