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According to the Time Used for Obtaining the Results of Positioning
Real-Time Positioning. Real-time positioning, based on the observational data of
the receiver, calculates the position of the receiver antenna in real time.
Non-Real-Time Positioning. Non-real-time positioning, also known as post-
processed positioning, determines the position of the receiver antenna through the
post-processing of the data received by the receiver.
According to the Receiver's State of Motion During Positioning
Kinematic Positioning. So-called kinematic positioning means that the position of
the receiver antenna is changing with the time in GPS positioning. That is to say, in
data processing, the position of the receiver antenna is seen to be variable over time.
Static Positioning. So-called static positioning is where the position of the
receiver antenna in the whole process of observation remains the same. That is,
in data processing, the position of the receiver antenna does not vary with the time.
In a survey, static positioning is generally used for precise positioning. The specific
observation model is to carry out static synchronous observations by multiple
receivers at different stations for several minutes, hours, or days.
GPS Receiver
Navigation Receiver
GPS pseudo-range navigation is the most basic GPS service mode. GPS navigation
uses the observation of distance (i.e., pseudo-range observations containing errors)
to more than four satellites to determine the position of the receiver. Navigation-
based GPS receivers (different from the phase measurement-based ones) generally
carry out the pseudo-range and Doppler measurements only by C/A code or P code.
They can receive navigation messages and calculate the position and velocity of the
antenna in real time. Except for American military and authorized users, users can
generally only use C/A code. As the most widely used receivers at present, they can
be used in military and civil navigation, providing positioning with a medium
degree of accuracy, and time transfer of relatively high precision.
Although GPS navigation receivers vary in type, their functions and operations
are similar. The work process of a common navigation receiver is as follows:
1. Power on.
2. Wait for satellite searching. The receiver searches automatically for satellites
that can be observed in the sky and locks onto the target, which will take a period
of time varying from seconds to minutes according to the different types of
receivers.
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