Document Type : Research Paper


1 Civil Engineering, University of Technology - Iraq

2 Department of Civil Engineering, University of Technology - Iraq


This  research aims  to  investigate  the  smoothing  of  the  pseudo-range raw  measurements  of  the  smartphone  using  a  Hatch  filter.  The  measurements  of  smartphones  suffer  from  high  noise  generated  from  low-cost  antennas  and  oscillators, which are designed to work in a certain way. These types of low-cost antennas  and  oscillators  are  entirely different  from  geodetic  instruments,  which  are  designed  for  high  accuracy  positioning.  The  GPS  measurement  data  were  collected   using   a   Huawei   P10   device,   41   minutes   and   24   seconds   GPS   observation  time  with  sampling  intervals  of  1  second  using  Geo++  Android  application.  The  GPS  measurements  are  processed  using  standalone  (epoch  by  epoch)  method,  by  MATLAB  software  developed  by  the  authors,  as  a  part  of  a software  package  for  processing  smartphone  GPS  measurements.  The  errors  in  raw  measurements  in  the  Easting,  Northing,  and  Up  (ENU)  components  when  using  standalone  (epoch  by  epoch)  method  are  ranging  from  -50m  to  30m,  and  the errors after applying the Hatch filter are reduced to have ranged from -10m to  5m,  the  raw  data  were  very  noisy  and  funded  it  has  many  cycles  slips  as  a  result of low-cost antennas and oscillators of smartphone’s. The cycle slips in the measurements  were  detected  and  found  that  it  was  the  result  of  jumping  the  errors to 27 m in northing and 43 m in up.


Main Subjects

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