In addition, a real-time algorithm for 
smoothing of the code pseudorange with 
carrier phase measurements is applied. The 
smoothing algorithm yields much better 
positioning accuracy than stand alone DGPS 
positioning. This algorithm is intended tp be 
used in low-cost vehicle tracking navigation 
system. 
Typical low-cost applications are ocean 
search-and-rescue, large vessel harbor traffic 
control, vessel route verification, and 
guidance and navigation systems for marine 
vessel. This includes dynamical positioning 
systems, autopilots, global way-point 
tracking systems etc. for ships and 
underwater vehicles. 
ACKNOWLEDGMENTS 
The authors would like to thank B. Vik for 
his technical assistance. 
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