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

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3
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0answers
130 views

How to determine and send alert SMS for next bus stop in a GPS tracking system?

In my gps tracking system (PHP/MySql) I have got 5 Stops for a vehicle. Whenever the bus reaches stop 1, the passengers at stop 2 should get an SMS alert. And in the same way for the sops followed ...
1
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0answers
163 views

GPS data cleaning - Sampling of track data

I have gotten a fairly large polyline-dataset of GPS-recorded tracks. I'd like to have a sample along the tracks for different variables. The problem is that the data has overlapping tracks. This ...
1
vote
2answers
153 views

consistency of cell phone gps readings

I want to record the location of each grave site in a cemetery for overlaying on Google maps. My Android cell phone (HTC Thunderbolt) reports an accuracy of between 10 meters and 25 meters. I'd like ...
0
votes
1answer
74 views

How to load sample points or coordinates on GPSMAP 62s? [duplicate]

Does anyone know how to upload 100's of sample points or coordinates from the GPSMAP 62s series to a computer? Does anyone also know the steps to create beeps or alarms when we approach these points ...
2
votes
4answers
169 views

Linking up GPS points taken from rail network

Bit of a newbie here, trying to work out whether any PostGIS functions can help with my task. Apologies in advance if my use of GIS terminology is not up to scratch yet. I have a large database of ...
4
votes
0answers
583 views

Microsoft Surface vs. iPad for mapping

I was recently introduced to the Avenza PDF app for iPad and I've been using it in the company I work for to help our field crews find their way around, and record waypoints and tracks. The app takes ...
2
votes
1answer
130 views

How can I transform Real-time Local position system coordinates into GPS/WGS84?

I have a local coordinate system built with Ubisense sensors and tags (it is a real-time locating system used to automatically identify and track the location of objects or people). The local ...
1
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0answers
284 views

How to approximate point to segment distance on sphere?

I would like to approximate the distance of a line segment from a reference point on the map (coordinates are gives as lat/lon). In the Cartesian coordinate system I would simply find the closest ...
0
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0answers
94 views

How to determine the Geoid model used by GPS receiver?

I have the following NMEA output by Holux M-241 GPS receiver: $GPGGA,144014.000,2227.0987,N,11410.1382,E,2,6,1.67,32.6,M,-1.3,M,0000,0000*7B I know that WGS84 height is higher than geoid height 1.3 ...
0
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0answers
49 views

How can i show online temporal data using Tracking Analyst?

I have online GPS tracking data . I'd like to show these data in webgis . I'm using ArcGIS Silverlight API . I used tracking analyst in Arcmap for offline temporal data but not online data. Is there ...
1
vote
1answer
78 views

How to debug Live GPS and base layer alignment issues in QGIS?

I am trying to use a bluetooth GPS with a couple of base layers in QGIS. The GPS/bluetooth connection seems to be working great...I can connect and disconnect without issue. I've set my project CRS to ...
4
votes
4answers
637 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 ...
3
votes
1answer
1k views

Replace Navteq maps by a free one in a car built-in GPS

My car (Opel Zafira) have a built-in GPS with Navteq maps (SD 900 NAVI). I wonder if it would be possible to update or upgrade the maps to an open source / free maps (like OSM). Or is it possible ...
2
votes
0answers
41 views

Calculate Moving Time

I am wondering how web apps like Garmin connect or Strava calculate a "moving time" from a gps track. For example I might record a GPS track on my Garmin GPS that has an elapsed time of 5:34:26 but ...
0
votes
1answer
73 views

What is the best way to apply the correct ZIP Code when Geocoding

I need to batch geocode a set of addresses, some of them are missing the zip code causing the lat/lng to be placed incorrectly, is there a good way easily correct this? I am using a few geocoders, ...
2
votes
3answers
2k views

Local Coordinate to Geocentric

The ultimate question, I need a transformation matrix to take a point in local space representing a roughly 500m x 500m place in New Mexico centered at -108.619987456 long 36.234600064 lat. The final ...
7
votes
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 ...
12
votes
4answers
778 views

GPS to map workflow, for non-GIS folk

What applications and workflow(s) do you use for gathering, displaying and storing GPS data, with your centralised corporate data, for people who are not GIS folk? We're in the process of ...
1
vote
0answers
78 views

looking for a GPS device which can transmit the location directly

I am looking for a GPS device or receiver that can transmit its own location to a specified configured server directly. there will be no medium like mobile phone or computer in between GPS and Server ...
9
votes
5answers
1k views

How can I find positions on my land?

I have about 2 acres of land, wooded and brushy. There was a survey and the corners have rebar. I am working on a site plan for house construction. I have two related problems: Finding a spot on ...
0
votes
2answers
83 views

How to choose spatial reference for GPS data?

We received GPs data from the vendor. I want using ArcGIS software to create XY event table and create a point feature class. What the spatial reference would be for the GPs data? Is it something I ...
1
vote
1answer
369 views

How to force ArcGIS iOS to use GPS data from External GPS device?

I created an app that will display the map and the location of the external GPS device. The scenario is using a wifly module to broadcast the GPS data of the GPS receiver in wifi. The app is now ...
0
votes
1answer
217 views

how to plot gps coordinates on my own raster map?

I have lat log values available in degree format, i donot know how to access raster maps using c#, and how to plot accurately. which libraries should i use and what are the controls avialable ,i am ...
1
vote
2answers
3k views

How to export and import gps points from Garmin 62S and QGIS

I'm pretty new to using QGIS and I'm curious about how to import and export GPS points created in QGIS. I have QGIS 2.0.1 dufour on windows XP and a Garmin 62s. Any suggested walk throughs would be ...
1
vote
1answer
996 views

How to convert from ITM ref to GPS ref ?

How can I convert from ITM ref (Israel new map) to GPS ref and from GPS ref to ITM ref? I need any C# sample code or formula for this. For example: 32.086156,34.769239 = 178364,665948 Or : ...
1
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0answers
73 views

Megellan Meridian and QGIS GPS Tools help request

I am using QGIS 2.0.1 on Ubuntu 12.04. I have a Magellan Meridian GPS and I trying to use the GPS Tools plugin to download waypoints to a layer in QGIS. I have successfully used the Gebabbel ...
2
votes
2answers
916 views

How can i convert from local coordinates to coordinates gps?

i don know if this is the right place to publish this. i am working with business object tool traying to make a kml file to be imported on google maps. I dont know much about geographic systems, but i ...
0
votes
1answer
3k views

Updating position for a list of markers

I am working with Google Maps. Specifically, I am working with http://hpneo.github.io/gmaps for a gps tracker simulation, here I need to update the position on each point. At the gmaps script, ...
2
votes
1answer
255 views

Is there any information in Sky Plot that is not in DOPs chart in terms of predicting accuracy in the field? (GPS data collection planning)

Joe only looks at DOPs chart and weather report for mission planning. Moe looks at both DOPs chart and Sky Plot and weather report. Is Joe missing out on something relative to Moe in terms of ...
2
votes
1answer
89 views

Open Source + Offline Geo Notebook

I am looking for an open source offline software to record points of interest that I might visit at a later date. Let's say I am reading a book about Alaska, I'd like to take notes about interesting ...
1
vote
1answer
81 views

snap GPS points to sidewalks

I have whole bunch of GPS coordinates collected from a device and sometimes they shift around 10m. Is there anyway to filter/modify points and snap them to sidewalks? So far I've written some ...
1
vote
1answer
46 views

How to merge intelligently GPS sensors?

I'm working on an application with a lot of GPS sensors, for each vehicle and person in a scene. I want to show a vehicle and his occupants in the same marker. But I can't get the vehicle occupants ...
1
vote
3answers
112 views

Is there demand for a higher resolution alternative to GPS tracking in the GIS market?

If there was an alternative to GPS that provided higher resolution tracking, what applications would there be for it in GIS? Note that this means higher resolution, but not necessarily higher ...
7
votes
3answers
283 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 ...
0
votes
1answer
268 views

Why do points shift when reprojected from WGS84 to a state plane coordinate? [closed]

We have a Trimble unit we use to collect equipment. We collect the data in WGS84 and differentially correct it and then reproject it to a state plan coordinate system. The points always shift the ...
2
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0answers
225 views

GLONASS Satellite Position Prediction using Almanac Data

GLONASS ICD has a section named "Algorithm of calculation of satellite motion parameters using almanac". It gives the formulas in order to calculate the position and velocity of the satellite. ...
4
votes
4answers
753 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?
11
votes
1answer
550 views

How to find ring of coverage of GPS Satellite on WGS-84 ellipsoid?

Given the following: Time, t The set of IS-200 Ephemeris data, E, of a GPS Satellite corresponding to time t The ECEF position of the GPS satellite, P=(x,y,z), derived from the time and ephemeris, ...
0
votes
1answer
90 views

Photos layer in Openlayers

I have some photos. They have GPS information. I want to add they with a layer like markers to Openlayers map. How can i do? Thank You.
8
votes
2answers
696 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 ...
0
votes
0answers
82 views

QGIS, SpatiaLite and GPS integration

I have QGIS an, access database and a Haicom gps all connected and running on a windows 8 machine. I want to integrate all 3 items so that while in the field i can enter information into the ...
21
votes
4answers
9k views

Why is GPS a free service?

The Global Positioning System (GPS) is a free service that is owned and operated by the U.S. Government and is always available. When we buy a GPS device, we don't pay a monthly fee or pay a tax for ...
0
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0answers
53 views

Combining two separate shapefiles with undefined projections out of Leica

So this is a mess. When the software outputs I have two shapefiles. The projections aren't defined, but I know one is WGS84 and the other is NAD 83. The NAD 83 includes northing easting and ...
0
votes
2answers
97 views

Add waypoints to ArcMap using GPSBabel

I've been trying to add waypoints to Arcmap for some while now. I have a Mac OS X 10.6.8 and have finally found GPSBabel that is compatible with mac. My current problem is to convert the waypoints ...
0
votes
0answers
135 views

Points warped when exporting to shape file (position off in Qgis when imported)

I have just purchased a used Trimble GeoXH and I have done some surveys. I did the differential corrections in Trimble Pathfinder Office 4.10. I have exported the corrected and uncorrected files and ...
0
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0answers
50 views

How to calculate GPS coordinates of one location relative another location? [duplicate]

In location “A” I know longitude (lonA) and latitude (latA) (Altitude is 50m). Relative to location A I know the horizontal (p) and vertical (q) distances to location “B” (B’s Altitude is 0m). I want ...
2
votes
1answer
105 views

What is a reasonable time to get a gps fix with 10 meters precision?

I hope I'm asking this at the right part of Stack Exchange. Please bear with me if I'm wrong. I'm developing some gps based applications. The demands I have for precision are not very high, but I ...
1
vote
1answer
22 views

Is it possible to calculate the route when source and destination having same junction using A* algorithm?

I am using A* Algorithm to calculate the shortest path. The route was calculated based on the junction. Shortest route was calculated when there was two or more junction in between source and ...
4
votes
1answer
2k views

What is a .ssf file?

What exactly is a .ssf file? I am refering to the .ssf files used with Trimble GPS units. I am aware that it is some sort of post processing correction file, but I do not know more than that.
2
votes
0answers
209 views

how to make decent sense from scattered river depth measurements

I sampled river depth at scattered positions and I want to be able to make a map and GIS layers out of it. My problems are: As the river meanders the interpolation I do in scientific packages i,e. ...