Open Journal Systems

Pseudorange smoothing by carrier phase an analysis of the tecnique

Mauricio Ihlenfeldt Sejas


Baseline positioning with carrier phase observations provide the best
GPS results, however these observations require ambiguities fixing. On the
other hand, code pseudorange positioning are not ambiguous, but the accuracy
is not enough for the most part of the applications because it gives some meters
accuracy. The pseudorange smoothing is a process provides intermediary
accuracy, in other words, the accuracy is not so good as the carrier phase
observations and is better then pseudorange observations alone. The idea of
smooth pseudorange by carrier phase is to combine phase (mm level) and code
(m level) observations. In principle the more data are used in smoothing more
accurate is the positioning, and no resolution ambiguity is necessary. The
objective of this work is to explore the pseudorange smoothing technique
showing its fundamental principle and its positioning accuracy. Observations
from absolute positioning was smoothed with L1 alone and with both carriers
phase (L1 and L2). The processed results showed more precision in positioning
with pseudorange smoothed than original pseudorange from code. In the most
part of experiments the pseudorange from smoothing process are more accurate
and more precise than pseudorange from L1 smoothed and original code. In
baseline mode results showed accuracy better than 1 meter using pseudorange