At present, there are two schools of pseudorange hardware delay for receiver clock error absorption in non-combined ppp. One is that the receiver pseudorange hardware delay of the first frequency is completely absorbed by the receiver clock error, and one is estimated at the second frequency. Pseudo-range deviation parameters need to constrain the ionospheric delay parameters at the same time; the other is that the receiver pseudo-range hardware delay of the first and second frequencies without ionospheric combination is completely absorbed by the receiver clock error.
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pppwizard is the first type, and gamp and rtklib are the second