This tag refers generically to *any* space-based satellite navigation system that provides location and time information.

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11k views

Using android phone to plot GPS points?

I was wondering if I could use my android phone (HTC Wildfire) to plot gps points and export these into GIS software (I have QGIS and MapInfo). Thanks, Alan
8
votes
2answers
6k views

What algorithm should I use to remove outliers in trace data?

I have GPX traces and want to remove outlying observations. There are some route points that are impossible because it would require acceleration that the vehicle can not achieve. Are there good ...
8
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2answers
2k views

How do I group near points with GPS positions?

I'm an IT person so I don't know too much about projections and so on, I hope you can help me. I have made an application for Android that collects a GPS position, so I have the latitude and the ...
8
votes
1answer
135 views

Is there a geodetic benchmark that is fixed with respect to plate tectonics?

I see that NGS benchmarks are used to monitor the movement of geologic plates. Is one of the benchmarks assumed to be in a fixed location, with movements of all other benchmarks measured with respect ...
8
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3answers
3k views

Example of a Dynamic Map Service that frequently changes?

A requirement of our web application is to automatically refresh a particular dynamic map service on a timer. Requirement relates to a client who has a dynamic MS that consistently gets updates ...
8
votes
1answer
918 views

Cleaning GPS track data

I have data captured with a GPS tracking unit. Some track have bad/cold starts and the only way to determine the track quality is by using the altitude. Unfortunately I don't have the raw GPS data and ...
8
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1answer
234 views

Analysis of GPS error

I'm wondering if there have been any studies which attempt to analyze or characterize GPS error distribution over different situations/conditions (e.g. surrounded by tall buildings/mountains, ...
8
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0answers
313 views

Is there open source GPS post-processing software? [duplicate]

Possible Duplicate: Post Processing GPS Data with open source software Here at the office we have a couple of 15-year-old Trimble 4700 and 4800 units but now we don't have the software to ...
7
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4answers
5k views

What data is sent from GPS satellites to receivers?

I know more or less how the GPS system works. But I would like to understand it in more details. Exactly what data is sent from a GPS satellite to a GPS receiver? I think there is multiple types of ...
7
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3answers
12k views

Accessing GPS data with JavaScript in real time

Is it possible to access GPS data in real time on a smartphone with JavaScript (without an android or ios application I mean)? Thanks
7
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3answers
1k views

Register and display real time tracking of my smartphone (gps) on a map

I have 2 smartphones (android galaxy and iphone) and i would like to display the position, according to the gps coordinates, on a map. Is there any app to download or any kind of service where i ...
7
votes
3answers
4k views

Do's and Don'ts for GPS Localization

We have recently purchased some new GPS survey gear (ProMark 500) and we have set up a localization around the town using some of the known survey marks. While I'm pretty confident that I have got it ...
7
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1answer
182 views

Approximating GPS coordinates for a point from n expected locations

I'm trying to find the coordinates of my point of attention (point X,marked blue). I used the GPS device of my car to collect the coordinates according to where I parked my vehicle each time I visited ...
7
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4answers
4k views

Garmin etrex raster maps support

I currently use an excellent set of printed topographic route maps for mountain biking. I would like to scan the maps, georeference them, and upload the maps to a handheld GPS device. Does the etrex ...
7
votes
3answers
14k views

How can I plot GPS coordinates on Google Map

What is the best way to plot GPS coordinates on a Google Map? Are there any tools that can do that (written in python specifically)?
7
votes
4answers
8k views

How to capture accurate GPS points using mobile devices?

I'm currently working in Vietnam as a climbing guide, but am putting my GIS skills to use by doing a side project for the company involving the mapping of climbing routes. Along with another employee ...
7
votes
2answers
5k views

postprocessing GPS coordinates with RINEX data to improve precision?

Im doing some mapping for OSM in my region and I am curious if the precision of tracks from a GPS Receiver can be improved if they are post processed with RINEX data. The tracking is done with a ...
7
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3answers
27k views

How to make work tablet integrated GNSS (GPS) on Windows 8 with QGIS?

I have tablet - Dell latitude 10, running Windows 8, with integrated Broadcom GNSS Receiver BCM47511 (GPS,Glonass...). Because it is integrated GPS and Windows 8, there is the "new" way of providing ...
7
votes
4answers
689 views

Is there a way to identify and remove similar GPS tracks in PostGIS or ArcGIS?

I have a large number of GPS tracks from a number of different users. I'd like to identify tracks that take the same route and remove those duplicates. For example, a user takes the same streets from ...
7
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2answers
3k views

Using OpenLayers (with OpenStreetMaps) and PostGis for rendering data acquired from GPS tracking device?

I'm researching and planing to acquire data from GPS device and store them in postGIS database, then use geodjango to process/work them out and finally chart them on a map with OpenLayers. Will these ...
7
votes
3answers
1k views

Using PROJ.4 library to transform from local coordinate system coordinates to global coordinate system using ground control points?

I have a point cloud whose coordinates are with respect to a local coordinate system. I also have ground control points with GPS values. Can I convert these local coordinates to a global coordinate ...
7
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2answers
1k views

How to Georeference Photos With No Spatial Reference?

I have about 100-200 field ground shot photos I would like to overlay in ArcGIS 10 that have no spatial information which I need to somehow develop using a photogrammetric formula. The camera was ...
7
votes
1answer
226 views

Unable to load .gpx file from Python Console

I'm trying to create a plugin which will extract the gpx files and load them onto the active layer window in QGIS. While I'm able to load it using the QGIS GUI from Layer>New Vector Layer, I'm not ...
7
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3answers
530 views

How to improve positioning of images taken with GPS and Gyro info?

I'm sort of 'recreating' google street view with MIT right now. We have a car with a camera on top and we're driving at 10mph down a road. As we drive we're shooting pictures at 30fps and each photo ...
7
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3answers
819 views

GPS integration with multiple waypoint routes

I'm building a system that needs to get the output of a route optimizer into the hands of a driver who intends to make deliveries on that route. Whilst I can supply this to the driver as a printed ...
7
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3answers
716 views

Recommended driverless GPS loggers?

There are a bunch GPS loggers out there, but a good portion need software to download the data onto a computer. Some of the software is Windows-only, but others are Mac-compatible (what I need). ...
7
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0answers
1k views

Calculating compass bearing between two GPS coordinates… with a twist [closed]

I'm building a virtual tour application that uses Google's streetview code to render the panoramas into a non-distorted view. Each panorama has 1 to n links where the user can select to move on. I ...
6
votes
5answers
1k views

Does the strength of GPS weaken in rural areas?

Does the strength of GPS weaken in rural areas? For example, based on how the satellites work, would the strength in the centre of Australia differ from a populated city in Europe?
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5answers
2k views

How can I get my GPS track data into a graphics program?

I'm using a Garmin Edge 705 bike GPS/computer unit, which produces .gpx files. I can use the standard software it comes with to plot on Google Maps etc, but I'd like to be able to output just a vector ...
6
votes
4answers
4k views

Free MobileGIS like ArcPAD

I'm looking for open-source program like ArcPAD. I have read all questions and answers, but i find nothing. I need the program for PDA (Dell axim x51v + GPS modul) and I want mapping points (trees or ...
6
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4answers
2k views

Matching GPS tracks

I'm looking for a proper way to process multiple GPS tracks (so time ordered list of lat/lon points) and match/classify that segments, that are covered by multiple tracks: So it's not about ...
6
votes
3answers
5k views

How to transform GPX-tracks into elevation-tracks with any GIS?

I have a GPS track in GPX format available from a recent bike tour and I need and want to do some analysis on the tracks. I'm wondering whether there is any way to transform the GPX data into an ...
6
votes
1answer
2k views

How to filter wrong GPS readings?

I have absolutely no experience with GIS, it just so happens that one of the hobby projects I am doing at the local hackerspace includes tracking a model boat with a GPS... I hope this is the right ...
6
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2answers
129 views

How does a GPS device determine bearing?

Following a discussion on Math and this particular comment, I am wondering how a GPS receiver determines its bearing. As I understand it: GPS is not a directional system, thus bearing can only be ...
6
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2answers
2k views

Storing GPS tracks with timestamps in PostGIS

I need to store a series of GPS points with timestamps in the database (traces of various vehicles). I am wondering which of two approaches to choose for storing them in the PostGIS table: 1.) Each ...
6
votes
3answers
245 views

Can I access Trimble logged positions in ArcMap10?

We recently walked a fence perimeter with a Trimble Ranger, auto-logging positions at 5 second intervals in a generic point file. The exported file acknowledges over 800 points, but only displays the ...
6
votes
1answer
12k views

How to batch convert Garmin GDB to GPX?

I need to convert a lot of garmin GDB files to GPX in order to convert it to another vector format. Is there any tools available can do a batch convert from garmin GDB files to GPX? Using MapSource ...
6
votes
2answers
905 views

Managing error with GPS routes (theoretical framework?)

I'm looking for the appropriate theoretical framework or speciality to help me deal with understanding how to deal with the errors that the GPS system has - especially when dealing with routes. ...
6
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2answers
4k views

GPS Module Without Velocity or Altitude Limitations

I am looking for a GPS module that I can use in a high-altitude project. The problem I have discovered is that GPS manufacturers are required to place a set of restrictions on GPS modules. The ...
6
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1answer
515 views

Simulate (Mock) GPS Tracks

I have the following scenario: 1) I need to create GPX files for use in testing of a mobile device. 2) The tracks to be described within will span large distances over long time periods (i.e. it's ...
6
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1answer
2k views

Calculating absolute precision confidence number from Dilution of Precision indicators from GPS receiver

End-user GPS receivers typically show an absolute confidence indication, such as Within 25 Metres, for the calculated position. I am parsing NMEA data from a GPS unit and wan't to calculate a similar ...
6
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1answer
60 views

How to improve GPS recording?

The image shows as example a small loop by car, recorded by two Garmin Dakota 10 devices. It seems both devices have had difficulties caused by the surrounding buildings, the "blue one" seemingly had ...
6
votes
1answer
459 views

Differentially correct GPX file

Is there any way to differentially correct a GPX file using free or open-source tools? Does a GPX file contain the necessary information for differential correction (I can put the timestamp in it ...
6
votes
2answers
687 views

Map-matching GPS points to the road network!

I am quite a newbie in Postgres and Postgis so please be simple and clear :) I am trying to do a simple map-matching (or path-inference if you wish) of some GPS points. I am using postgres(postgis). ...
6
votes
2answers
429 views

Finding Lost Samsung S4 with Lat/Long Coordinates

I lost my Verizon provider Samsung S4 phone while running on a narrow trail surrounded by brush. The phone no longer has power. Using Google Location History I obtained that Latitude and Longitude ...
6
votes
1answer
188 views

GIS Server for web service

I am building an app that has some GIS requirements that go a little beyond (I think) what I can retrieve from existing online web services resources so I am attempting to build a server of my own to ...
6
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2answers
222 views

Survey Data to GIS database [closed]

This is a General Question on a possible workflow for Survey Data directly to ArcGIS In most GIS/Survey workflows there is a field collection team and backoffice GIS team. When the availability of ...
6
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2answers
2k views

Trimble GeoXH vs GeoXT and GPS Correct

I am about to purchase a new GPS unit. I currently have a GeoXT and have used the combo of GPS Correct/ArcPad with GPS Analyst/ArcMap to correct the collected data to submeter (or close to it). ...
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3answers
708 views

Tracking a vehicle without GPS device

We are planning to write an application which have to track the user driving in his truck in the cities like New York city accurate upto which lane he was driving on. In the cities with those tall ...
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2answers
2k views

Why is the GPS Reference Meridian 100m to the East of the Prime Meridian?

Apparently if you stand at Greenwich then your GPS will not say you are at longitude zero. This is because the GPS reference meridian is about 100 metres to the east of the prime meridian. My ...