Processing Method: Define which measurements are processed (e.g., ‘Code + Phase’ or ‘Code only’)
Adjust phase to code: By activating this option in a ‘Code + Phase’ processing, raPPPid will shift the phase observation on each frequency by a full number of cycles. This full number of cycles is initialized in the first epoch a satellite is observed by calculating the difference between phase and code observation. It is kept as long as the phase is continuously observed. By doing so, the phase ambiguity is kept small (e.g., numerical reasons) or reasonable phase processing enabled (e.g., the absolute values of phase measurements in the RINEX file are completely off from the code measurements). Check the function AdjustPhase2Code.m for details.
Smoothing factor: Smoothing Factor [0; 1) for Code processing with Doppler or Phase smoothing (create_LC_observations.m). 0 = no smoothing, 0.99 = very strong smoothing. Choosing a smoothing factor of zero corresponds to a ‘Code only’ processing.
Doppler Smoothing: Csmooth = (1-fac) C + fac (Csmooth,old - λ dt/2 (Dold + D))
Phase Smoothing: Csmooth = (1-fac) C + fac (Csmooth,old + (Lold - L))
Define which part of the RINEX file is processed. You can either select the epochs (e.g.,1 to end - complete file) or choose a time interval in seconds of day or hours of day.
Define if and after which period a reset of the PPP solution is performed. Such a reset of the solution is like a complete restart of the processing. This option is helpful in studying convergence behavior.
Here you can define epochs that should be skipped in the epoch-wise processing. You can decide to perform a reset after skipping some epochs. This option might be useful if some epochs of an observation file are suspicious.
Elevation Cutoff: Satellites under this elevation angle are excluded. Enter 0 if you do not want to use this option (not recommended).
SNR Cutoff: Observations with an SNR under this value are excluded from the adjustment/filter. This might be useful for observation data from low-cost receivers. Enter NaN if you do not want to use this option. Enter multiple comma-separated or white-space-separated values to define frequency-specific thresholds. Enter, for example, “20 15 10” to use 20 dbHz, 15 dbHz, and 10 dbHz as thresholds for the first, second, and third processed frequency.
Signal Strength Threshold: Typically, a digit for the signal strength is included in the RINEX file for each observation (signal strength digit). Here you can define a threshold. Observations having a signal strength digit under this threshold are excluded. Enter NaN or 1, if you do not want to use this option. Check the RINEX 3.04 specification, section 5.7, or the function check_SNR.m for details
This option is especially recommended for PPP solutions over a long time span (e.g., several hours) because it improves the stability of the solution against, for example, multipath or outliers. However, it proved to be dangerous sometimes because this function might exclude many observations.
If used, raPPPid checks the observed minus computed (omc) values before the adjustment. In other words, a check is performed to see if the actual observations fit the observation model. If the omc for a specific observation exceeds the defined fixed threshold for code or phase, this observation is excluded from the adjustment.
Furthermore, it is possible to define a number of epochs n and a factor f for code observations. Then raPPPid calculates the omc standard deviation of the last n epochs over all satellites and multiplies it with f. If the resulting value is lower than the defined fixed thresholds, it is used as the threshold for the omc. Enter NaN if you want to use the fixed threshold only.
By activating this option, raPPPid will try to detect and compensate receiver clock breaks during the epoch-wise processing. The approach introduced by Guo & Zhang (2014) is used. Please check the function DetectReceiverClockJump.m for details.
Exclude certain satellites completely over a specific time span defined in epochs from the processing. Enter the PRN of the satellite in the raPPPid internal format (e.g., 223 for E23). Do not enter the start and end epoch to exclude a satellite for the whole processing.
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