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

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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 ...
5
votes
2answers
94 views

Are speeds in GPS data obtained by detection or calculation?

I have been doing a study into taxi behavior with its GPS data. I could calculate taxi's mileage by either longitudes and latitudes or times and speeds in the data. Since there are several errors in ...
6
votes
2answers
226 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 ...
2
votes
1answer
2k views

How is Precise Point Positioning (PPP) exactly done?

I am looking for a positioning accuracy that is higher than normal consumer-grade GNSS receiver (mostly GPS/GLONASS hybrids with +- 5m precision). I came across RTK with dual receiver setup (base ...
1
vote
0answers
9 views

from/to ellipsode to/from cartesian conversion

i am trying to convert from/to ellipsoidal coordinates (lat,lng,alt) to/from cartesian(x,y,z) i wrote the below code to do the conversion, but given the initial values of the gpsLat and gpsLng i ...
0
votes
0answers
43 views

How can one reprogram a cheap GPS tracker device?

I was wondering if I could get a cheap GPS tracking device such as this one on amazon and reprogram it to send the co-ordinates to my own server? I would then like to generate reports from the DB on ...
1
vote
1answer
23 views

Creating points with co-ordinates in QGIS to upload to GPS

I have generated a random point within a set area. I have done this using the Google Maps plugin layer. The CRS is set to WGS 84. I want to get the co-ordinates for this point so I went into the ...
0
votes
1answer
62 views

Exporting Images Linked with Survey data , from a GPS to GIS format

We were setting up a workflow system , where in we attach Survey images to our collected point data ( Leica GPS) . The same can be viewed in Softwares like Leica Geo office, but a GIS export of the ...
11
votes
4answers
1k views

Real time map matching using ArcGIS Desktop?

I am working on a project which requires real time map matching. I am currently using ArcGIS but not sure whether it will work. Here is what happens with my system: the cell phones sent GPS fixes ...
0
votes
0answers
37 views

Testing a new GPS positioning method

My PhD research involves developing a new positioning algorithm for GPS. The focus on the research is on the mathematical aspects and not to build a GPS receiver. However, we are interested in testing ...
0
votes
0answers
10 views

Where ionospheric coefficients come from?

There are 8 coefficients in broadcast GPS message (ION ALPHA and ION BETA in the header of RINEX navigation file) that are the part of the Klobuchar model. Is there an open source of this ...
6
votes
2answers
153 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 ...
5
votes
3answers
760 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 ...
3
votes
2answers
177 views

API for land use/land cover

I'm making a mobile game that uses GPS to interact with the real world. The game should be able to "see" what terrain/land use/land cover the user is currently in. Ideally, the game would send the ...
0
votes
0answers
17 views

SPOT GPS (Find me Spot) Feeds for ArcGIS Online

Does anyone know if it's possible to get a feed from your SPOT GPS account and turn it into a live tracking layer to use in ArcGIS Online? I did find what appears to be a SPOT testing account from ...
0
votes
1answer
50 views

How GPS coordinates grows?

I'm working on a project which uses GPS coordinates. I have a UAV that flies, for example, over a meridian or a parallel. I suppose that the coordinates I'm reading from UAV are always increasing or ...
2
votes
0answers
71 views

how to transfer GPS device coordinates into mobile android app?

i'm trying to make an android app that collects data field in high accuracy, since the phone native GNSS doesn't provide highly accurate coordinates, i want to use Coordinates provided by a real GNSS ...
0
votes
0answers
199 views

Windows desktop application that allows to visualize, edit, download, upload and convert GPX files?

I am looking for a simple application that will allow me to visualize GPX data, edit and create new GPX tracks, areas and points and download/upload GPX data to and from devices. This application ...
0
votes
1answer
46 views

Add points at specific gps coordinates in qgis [duplicate]

I created a layer in order to draw points with the azimut and distance plugin. IT didnt work at all. There was not even 1 point created. I followed the tutorial here: http://www.teuderun.de/workshops/...
4
votes
2answers
204 views

Calculating new satellite position given pseudorange measurements

I'm looking for a reference/text for an explicit formula to calculate a satellite position given pseudorange measurements from later epoch times. I've seen a lot of matlab code on the internet but I ...
1
vote
0answers
32 views

Creation of 3d terrain from real data [duplicate]

Possible Duplicate: 3d terrain from data in postgres I am pretty new to spatial database and 3D data. I have a project where i have to create a 3d terrain from data being taken by me by a sort ...
3
votes
2answers
85 views

How to rename several layers at the same time?

I have got some GPS tracks (MultiLineString). As I import them to QGIS, they look like this: I would like to merge them and to do so, I have to rename all of them like this (picture 2) otherwise an ...
0
votes
0answers
9 views

Getting *dop values from a skytraq based gps logger

I am preparing to a project where we are to log several free ranging animals. At the moment I am looking at different gps-logger. One of the more promising is the canmore 740. One issue I have with ...
13
votes
3answers
1k views

GPS Elephant Tracking: Utilizing A-GPS, WAAS, DGPS and Understanding HDOP, NSAT, and ZDA

*I'm using a GPS data logger (qstarz bt-q1000xt) to track the movement of zoo elephants, and I have a variety of technical questions. I've had limited success receiving answers from the vendor. You ...
2
votes
1answer
266 views

How to get all gps points on a road from osm data?

I'm trying to extract gps points on roads in a region. For each road, I need a gps point on that road every 10 meters. I'm aware that Google Map API offer such way points, but due to the latency-...
16
votes
8answers
6k views

Location-based game using GPS

I am not sure if this forum is proper place for that kind of question but i hope to get some advice... I looking for some scenario (examples, ideas) for urban game (location-based game) with usage of ...
1
vote
1answer
74 views

Method to determine a person's city/state using location coordinates?

I am working on data-mining project where I have to map a bunch of tweets to US states. I can get the lat/long coordinates from the tweet json, but I am not sure if it is possible to map those ...
1
vote
0answers
80 views

GPRS data receiving in Java [closed]

i am creating a java program that will receive data from GPS tracker device and will store it in MySQL. for this purpose i need to create a GPRS connection for receiving data. Can anyone help me how ...
2
votes
0answers
50 views

Can I read ephemeris data from GPS receiver?

I want to filter the GPS data. when I use the low cost GPS receiver, it gives erroneous data. therefore I want to apply some filtering technique. How can I read ephemeris data from GPS receiver? I ...
1
vote
1answer
127 views

Average stationary position with GPS

Is it possible to average a stationary position with a GNSS (GPS, GLONASS...) with a centimeter accuracy without external corrections (like differential or RTK)? If so, how long does such averaging ...
2
votes
1answer
266 views

How to compare GPS absolute positioning receiver accuracy

I have two different types of GPS modules which are in absolute positioning mode (pseudorange data) Lets say one of them is attached in microcontroller (such as arduino, rasbpy, etc) and the other ...
22
votes
6answers
6k views

How correct is the “Accuracy” value given by GPS devices?

I have a Garmin Forerunner 305 and a Google Nexus One Android phone. From the GPS on both these devices I can get a "Accuracy" value that is usually between 6-20 meters. How much can I trust this ...
0
votes
1answer
424 views

Accuracy of GPS and HDOP

Given a handheld GPS with an accuracy of roughly 2 meters (verified through field tests) and an observation with an HDOP of 1.2, the accuracy of that one observation should be within 2 meters X 1.2 of ...
4
votes
1answer
271 views

Calculating Distances between coordinates

I have 75 coordinates in WGS84 that I brought in from an Excel table. They are now on my imagery basemap spanning across about a half mile on either side of a dirt road in Prescott National Forest in ...
4
votes
3answers
95 views

What view of sky is required for RTK GPS

When using RTK or differential GPS technologies, considering the Base has a clear unobstructed view, what view of the sky is required to be able to get an accurate fix with the rover when is moving (...
0
votes
0answers
54 views

Python GPS Observation Equations

I've been trying to write some code that will take pseudo-ranges and satellite positions and then compute the observer's position. I've been trying to follow through this book, but the crucial stage ...
1
vote
0answers
21 views

Plotting GPS plot without uploading data

I'm not sure if this is possible or not, but I'm wondering if its possible to plot a GPS dataset without uploading the data first to CartoDB. I've been analysing some data by uploading the postcode ...
1
vote
0answers
23 views

What is the lowest and highest possible pseudo-range?

I am trying to compact the required data that needs to be sent to the server to post-process the receiver's position. To do this, I figured it'd be possible to offset the pseudo-range by a fixed value....
0
votes
1answer
27 views

Entering Track from Garmin to GIS not getting basemap and orthomap to line up with Track?

I collected a GPS path on a flight and I would like to condense the path to the place where we landed and took pictures (condensed area at base of map; I want to delete the other part of the line). ...
3
votes
1answer
41 views

problem with the import of a gpx file in any program

I have difficulties to import one particular gpx file. I got it via email and it displays some tracks. 10 segments and 5500 waypoints. i tried as follow: QGIS, also with GPSBabel Google Earth ...
1
vote
1answer
390 views

Trimble Net R9 Base Station Receiver File Structure

We just installed our new GPS Base Station Net R9 receiver that replaced our old 5700 receiver. The old 5700 used Trimble's GPS Base software, which the new Net R9 does not. My first problem that I ...
2
votes
0answers
101 views

Find gravity normal by ECEF or GPS coordinate of point

How to find gravity normal by ECEF or GPS coordinate of point? Is it the same as normal to elipsoid? Is this ordinary way to calculate normal to ellipse? I'm not quite sure which altitude is ...
0
votes
1answer
36 views

How to set datum in GPS connection setup window in ArcFM Viewer for ArcGIS Engine Application

I have a custom application based on ArcFM Viewer for ArcGIS Engine. I want to use an external GPS receiver with that application and the setup window does not let me choose a different geographic ...
2
votes
1answer
96 views

Setting elevation data for tie points in Pix4D

I am currently working in Pix4D and am trying to assign elevation data to my selected tie points. I have aerial images taken using a camera with GPS from an aircraft and am working with a fairly ...
1
vote
0answers
78 views

Determining accuracy of coordinates from handheld GPS?

I'm working on a project for class, and I'm mapping GPS on Google Earth with a KMZ file. I used a handheld GPS 24°6.691'N + 74°27.833'W. How accurate is my coordinates? I know I'm in decimal minutes!...
11
votes
10answers
4k views

Need a Benchmark GPS Trajectory data-set? Anyone?

I'm looking for a benchmark GPS data set, available for research purposes for free. I've found GeoLife GPS Trajectories dataset from Microsoft Research but I find it a little incomplete. What I need ...
0
votes
0answers
57 views

How to create speed maps with gps data

I am looking to create a speed map from gps data, one of the problems is that the data overlaps due that the road is a track. How can be the best way to plot this map? I have Qgis and ArcGIS options ...
1
vote
0answers
46 views

How can I calculate times with gps data using random points on the track? [closed]

I have GPS data from a car that is circulating all the time in a closed circuit. I need to put a few points along the route, about 3 or 4 and calculate the time it takes to get between points. These ...
1
vote
5answers
3k views

Solutions for uploading maps to GPS (forestry maps: roads, trails, hydro, polygons)?

I'm using a QGIS 2.2.0 Valmiera on a Windows 8.1 system Desktop. I'm a forester and I would like to have a cheap solution to load maps into the handheld Garmin 60, 62 or 64 series GPS. Free would be ...
1
vote
1answer
146 views

GPS tracking times

I have a GPS data on a closed road, where the cars riding laps, and I want to know how long takes to do 1 lap and also I want to add some points to calculate how long takes in specific sections. One ...