Xiamen Caimore Communication Technology Co.,Ltd
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Of course, there will be some deviation in positioning. For the mainly reasons,
see as below:
1. Atmosphere (especially the delay signal of ionospheric and tropospheric)
Ionospheric delay is caused by the refraction affection between the earth’s
ionosphere surrounding and electromagnetic waves, which makes the
changeable propagation velocity of the signal. Tropospheric delay refers to
the refraction affection between the earth’s tropospheric surrounding and
electromagnetic waves, which makes the changeable GPS signal propagation
speed changes.
2.Satellite clock deviation.
Due to quite sophisticated, the satellite can calculate the number of tiny
message information, for example, the atomic clock (Cesium). However,there
will be some minor deviation caused by such precision device but not means
perfect. In another word, the satellite will not in the state to be monitored
every second, even positioning continues to be monitored. In this case, if any
slight positioning deviation or satellite ephemeris error generated during this
period, it will affect the accuracy of the calculation when the receiver do the
positioning.
3. Ephemeris error ( the satellite orbit errors)
When performing positioning, the satellite has to calculated various
