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

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2
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1answer
955 views

What happened to Live GPS Tracking in 1.8.0-Lisboa?

Dang, I was just getting used to Live GPS Tracking in 1.7.4-Wroclaw. I downloaded the new version 1.8.0-Lisboa on another computer. The Live GPS Tracking thing was in the View pull-down menu in ...
13
votes
3answers
6k views

Advanced android app for mapping and GPS logging

I am looking for an android app able to log GPS data like coordinates, altitude, current speed and would be nice if also the GPS accuracy/number of satellites. Many GPS apps are able to display these ...
2
votes
1answer
2k views

how to calculate RMS 2D and RMS 1D, using python?

I would like to calculate: RMS 2D: standard deviation for the two coordinates of flat (67% confidence level) and RMS 1D: standard deviation for height (67% confidence level) What is the formula and ...
7
votes
3answers
777 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 ...
4
votes
3answers
585 views

API to suggest nearby streets

For an app I'm developing, I want to use the phone's GPS to locate it. I then want it to list streets that are nearby. The customer might be in his back garden for example, and this may be closer to ...
3
votes
1answer
98 views

set wrong GPS unit in “degree” and want to change to “meter” in GIS while editing

I want to edit the GPS result in ArcGIS, but I found that there is a problem. I set the wrong unit while I used the GPS outside , and the unit is "degree". Although the coordinate system is correct, I ...
3
votes
2answers
247 views

What is the minimal data necessary to reconstruct GPS location?

Imagine that a minimal GPS device is attached to a moving object (animal, shipping container, geocache object, etc). Every few months, data from the device is downloaded for post-processing. What ...
1
vote
0answers
369 views

how to correct the coordinate of points [closed]

I have some a layer which contains some points. The coordinate of the points should be GPS points. However, the coordinate of these points are not correct. What should I do? I am using QGIS. If I ...
3
votes
1answer
192 views

is the GPS network free or available for any device?

I have a question (I'm really sorry if is kind of dumb question). But if I have a device with GPS (smarthphone,pda,pocket pc, etc) Does the device need any additional service to enable GPS data? I ...
3
votes
1answer
337 views

How to overlay map onto a corner of an image, using that image's GPS exif data?

I have several hundred JPG images taken during a time lapse of a drive, with each image containing embedded GPS information. Is there an OS X friendly workflow that can allow me to: create a ...
3
votes
2answers
561 views

Classification of GPS trajectory

I need a detailed description of a GPS trajectories. I don't need to know what a GPS trajectory is, I already know it. Exactly I need a paper (better if scientific cut) that talk about different type ...
2
votes
1answer
5k views

How do I calculate a xyz-position of a gps-position relative to an other gps-position?

I have two gps-positions (lon, lat, alt) and want to get the position of one relative to the other one. (in meters, as x, y, z) How do I do that? Thanks in advance. Edit: The locations have a ...
9
votes
4answers
700 views

Does GPS signal quality depend on the chip manufacturer? Does it depend on weather?

(Sorry if GIS is not the right place to post this question to). Recently me and my school friends had a GPS software application project to pursue at the university. A device very similar to this ...
3
votes
1answer
2k views

File IMG from OSM

Is it possible to convert or open an IMG file from OSM? I don't find a solution for the visualization and conversion. Thanks
1
vote
1answer
181 views

Mobile location determination

I was wondering how Google Maps on my Android phone can locate me with a good accuracy when my GPS is disabled. At first I though it was with the cell tower but I'm not sure it can achieve this ...
1
vote
0answers
388 views

Holux GPS logger .itm fileformat

I'm looking for a spec sheet or a library to open and decompress .itm files from the Holux GPS logger. Has anyone worked with the proprietary .itm format already and can provide me with some usefull ...
6
votes
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). ...
3
votes
2answers
489 views

How to get the layers of my project to show while tracking with GPS?

I've been using/testing several versions of various GIS software and run into occasional issues. Right now, my biggest with QGIS is with GPS connection/downloading from/tracking. These are all ...
3
votes
3answers
8k views

Distance between GPS coordinates

Given a database of GPS points, a center GPS location, and a radius R (in meters), how can I find all points in the database that are within a distance of R of the center point? Will the distance ...
12
votes
2answers
2k views

Why is getting a GPS fix so slow?

I understand the basic concepts of GPS positioning system and the use of trilateration but I don't understand why it takes so much time to get a fix. On commercial GPS like TomTom it usually takes ...
1
vote
1answer
2k views

How do I calculate ECEF X,Y,Z velocities for GPS if I have no satellites

I'm attempting to simulate a GPS message where know variables are starting location, ending location, speed (m/s), and a bearing (0 - 359 degrees). How can I calculate the ECEF X, Y, Z velocities ...
0
votes
0answers
56 views

Calculate XYZ velocities between 2 ECEF points [duplicate]

Possible Duplicate: How do I calculate ECEF X,Y,Z velocities for GPS if I have no satellites If I have a starting location (Latitude/Longitude), a bearing (degrees), and a speed (m/s), how ...
7
votes
1answer
231 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, ...
1
vote
1answer
3k views

Go to X,Y dialog box

If someone gave you a x,y coordinate numbers he/she got from. I put the numbers in the X,Y events on my ArcMap and they are in Meters numbers. We entered the number into the x,y dialog box. The ...
6
votes
1answer
11k 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 ...
1
vote
1answer
621 views

Sensitivity of Garmin eTrex 30

I have a very good experience with Garmin eTrex Legend HCx - here and here they write that HCx has a very sensitive chip, that works in forest, deep valleys and in cities - and I can only confirm - ...
5
votes
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 ...
5
votes
1answer
434 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 ...
1
vote
1answer
406 views

What GPS unit can I use to track myself all day for a 10 day trip? [duplicate]

Possible Duplicate: Logging GPS and Accelerometer Data - Device Suggestion? I will be visiting China this October as part of a field studies course and I want to be able to take the ...
1
vote
2answers
324 views

Is there a time limit on post-processing GPS data with Pathfinder Office?

Do I need to post process my GPS data within a certain amount of time after collection? Do the services that provide the correction data to Pathfinder Office only make that data available for a ...
13
votes
5answers
8k views

How to get an elevation profile for a gps track?

I'd like to get a reasonably accurate elevation profile for a track recorded with a GPS (which often has very unreliable altitude data and occasionally none at all, depending on the model.) Does ...
1
vote
3answers
101 views

Looking for a website to produce a file using UTM or LL or LL to UTM or general

Is there a website that allow me to upload my GPS file from UTM to lat and long to produce a new output file ? I am looking for one to run a batch a list of UTM or LL to converstion them in either ...
4
votes
1answer
1k views

How to calculate accuracy of latitude/longitude

I'm updating a Windows Mobile application to capture location information using the built-in GPS hardware. The Microsoft API provides a method GPSGetPosition that returns the following struct ...
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 ...
4
votes
1answer
6k views

How to calculate Bearing between two GPS points

The following returns 150 degrees using C# converted from JavaScript Bearing formulas, but Google earth returns 210 degrees for the same values. The broken code is GetBearing() but I've also included ...
2
votes
3answers
585 views

GPS and GIS for real time monitoring of an object

How is it possible to store coordinate of object in server in real time using feasible hardware ( can be used by student) GPS into database and retrived in real time?? What are the names of ...
3
votes
2answers
428 views

GPS capable rangefinders or cameras that can capture lat / long data from a distance?

Anyone have experience using this technology? i.e. field verifications of structures where you need to capture the lat / long of a house that is 1000 feet from the road with limited access.
1
vote
0answers
343 views

Draw a skyplot with calculated ECEF values (in meters)

I have ECEF values that I calculated from ephemeris subframes 2/3. Using this information, I'd like to place these values on a skyplot based on my current location. I'm using a C# picture box for my ...
5
votes
4answers
966 views

Looking for software to interface GPS data with PC

I have GPS Unit from Garmin (GPS 18xPC). I'm looking for software I can install on my PC that will allow me to interface with the data I collect on my GPS unit. Any help will be great
8
votes
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 ...
6
votes
3answers
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 ...
11
votes
2answers
856 views

What Type of GIS Powers Automobile Navigation Systems

My sister-in-law was inquiring about where she can buy updated DVD's to load into her car's system. Obviously I know the dealer/OEM would love to rip her off for such data, and I knew of no ...
0
votes
1answer
1k views

how to convert the easting and northing to a point and saved in a feature class in ArcMap?

I write a program to decode the message from the GPS device to get the easting and northing , but I don't know how to convert the easting and northing to a point and saved in a feature class in ...
2
votes
2answers
978 views

GPS - Garmin 60CSX connectivity issue

I have a Garmin 60csx, about 2 years old and I have attempted to connect it to my laptop/ArcView (GPS toolbar) using the Detect GPS Port to no avail. There is no port number being displayed and that ...
16
votes
3answers
539 views

Lightsquared GPS controversy: Where is the analysis?

GPS World reports that Lightsquared's network of 40,000 transmitters will interfere with GPS signals. Initial technical analyses have shown that the distant, low-powered GPS signals would ...
3
votes
1answer
2k views

How to read multiple .gpx files in R [closed]

Suppose I have a number of .gpx files (these contain GPX waypoint data from a Garmin eTrex). I want to load them into R with different names and manipulate them. I can read one file thus: ...
4
votes
1answer
436 views

RINEX specs and OS library

Is there any OS library to read/write/process RINEX data? I've been wanting to start a OS library to read and write RINEX, which is something I need for a project, but not actually post-process them. ...
26
votes
7answers
2k views

Why don't they use cell towers like GPS satellites?

If my understanding is correct, a GPS satellite produces a pretty simple signal which is basically composed of its location and its time. Given 4 of these signals, then one can uniquely solve for the ...
3
votes
6answers
2k views

Garmin GPS 78 Interface

Does anyone know how to interface a Garmin GPS 78 Marine GPS with their computer to manage waypoints (upload, download, save, etc.) Previously I was using the MN DNR Garmin tool, but it no longer ...
1
vote
1answer
252 views

delorme gps and delorme X map alternatives

We have a group doing field work and are having issues using delorme gps and delorme X Map and Delorme X Map. Wondering if there is a way to connect the delorme GPS pn 40 to ArcReader / ArcExplorer in ...