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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2answers
101 views

Finding all ways that are partly within a bounding box

I'm trying to write a query that will return all OSM ways which are contained within a bounding box of min/max gps coordinates. I get these cooridinates from the greater london bounding box on ...
0
votes
1answer
29 views

Developing an iOS GPS App

I'm an experienced programmer looking to develop a GPS App with these constraints: I Need a turn by turn level of precision I Need to know if a street is one way or not I Want to calculate an ...
16
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4answers
18k views

What is the maximum Theoretical accuracy of GPS?

I was talking with a potential client, and they requested that we plot some points with GPS, with a maximum (or should that be minimum?) accuracy of 2 m. This is an area with no WAAS, and I was under ...
3
votes
2answers
207 views

Measuring Continuous Distance of GPS track in ArcGIS Desktop

I am looking for a way to quickly measure the distance covered of GPS tracks of foraging Seabirds. A tool that could give accumulative distance of point to point from the long and lat coordinates ...
0
votes
0answers
51 views

Is it possible to calculate area of polygons from GPS points without POSTGIS

I am new with GIS. Assume we use the UTM30N coordinate system. Is it possible to calculate an area (say a square box) by the 4 given points? (assume the points are in order, and the coordinates are ...
0
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0answers
52 views

Can I put a button that automatically inputs GPS coordinates into a google form? (or other spreadsheet populator)

I am currently creating a Google Form and part of the questionnaire requires the user's current GPS location. Is it possible for a button to be able to do this and automatically populate the field? Or ...
0
votes
0answers
29 views

True Altitude of GPS cooridnates

Given two points a=(lat1, long1) , b=(lat2, long2). I want to divide the line between a and b into points with equidistant length. (for example 100 Points) For each of these points i need to ...
0
votes
0answers
32 views

Is there any application that gives the real absolute altitude?

I defined a test already and I would like to compare the altitudes measured by different sources. I drove a path by a car, mounted a GPS and a pressure sensor in the vehicle. On the chosen path, there ...
2
votes
2answers
60 views

Compass Navigation With ArcGIS SDK for iOS

There's a sample provided by esri named GpsSample (I can't find a way to upload it here) Anyway, the sample includes multiple selections for mapview's locationDisplay autoPanMode property I'm trying ...
1
vote
1answer
17 views

Is there an Internet resource for GPS timeline?

I'm looking for a timeline of the evolution of GPS technology and accuracy for both civilian and military systems (since the advent of GPS). Any info will help.
1
vote
1answer
43 views

Determine when heading off course

How does google or other map providers with routing capabilities determine when you are not staying at the right course? I am trying to figure out how to implement this feature in my gps that I am ...
1
vote
0answers
211 views

Building a private GPS almanac server - practical experience

I'm trying to provide a source of GPS almanac files (in SEM format) for a non-connected / sometimes connected network. I know that I can download them from the USCG NAVCEN. However I don't want to ...
2
votes
1answer
30 views

Topology Editing using ArcView (now called Basic) license level of ArcGIS Desktop?

I am building a geodatabase from data collected on a GPS handheld in the field. The GPS device collects decently accurate information but I need to make sure all the polygons, lines, and points are ...
1
vote
0answers
81 views

Collector for ArcGIS PDOP and GPS collection configuration settings

My company just acquired a Geneq SXBlue II GPS receiver to pair with an iPad and the Collector for ArcGIS app. The functionality is awesome and loved by everyone, but since we have biologists on our ...
1
vote
0answers
11 views

Base station correction process

This concerns post-processing via base station correction in Pathfinder Office. I understand the base station is a known location and the GPS receiver's location is corrected relative to the base. I'm ...
0
votes
0answers
83 views

Anyone know an iOS data collection app that exports raw GNSS data for differential correction?

I am pretty sure the answer to this is "No", but throwing this question out there in case someone knows of something I haven't stumbled across yet. I am seeing less expensive GNSS units show up on ...
1
vote
1answer
48 views

How do I force gpspipe to read from a USB Serial device rather than a server address with a port and everything

I'm desperately trying to grab the simplest piece of information I can out of my usb dongle from the command line. A program of mine needs to use it so it has to be a STDIN/STDOUT type solution. I ...
0
votes
1answer
43 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 ...
0
votes
0answers
35 views

QGIS linked to camera for GPS based triggering?

Has anybody done this yet? I'm new to QGIS and have just started exploring. I'd like to integrate flight lines and camera triggering if anybody can direct me to the right forum or area. Thanks!
4
votes
2answers
233 views

Does iOS know the phone's location solely from cell tower, i.e. without GPS data?

Question Does the iOS operating system know the phone's location even if one could turn off the iPhone's built-in GPS module or if it was broken? Elaboration What I understand I understand that ...
1
vote
1answer
35 views

I want to trace a gps device

I want to create a device that should transmit its location to a server using anyother medium other than GSM. Bascially I need a tracking device which i could give to my worker and he goes to a forest ...
3
votes
1answer
50 views

Is there a method to tell which hemisphere a point belongs to, in WGS84 geoid, where the equator is an arbitrary ellipsis?

I use the WGS84 geoid (because I'm working with a GPS chip). I define an ellipsis that splits the surface in two parts, lets name these 'A' and 'B'. This ellipsis is defined by two points 'a' and ...
0
votes
0answers
27 views

How to get correct measure with PostGIS SQL query? [duplicate]

First of all, sorry my bad english. I am new at gis. So I want to measure my road. I want to use measure unit kilometers. But I am a bit confused. I have a garmin etrex gps device. So I get my ...
2
votes
2answers
167 views

Detecting patterns in vehicle GPS data [closed]

I need to analyze data uploaded from vehicle GPS devices to detect travel patterns and then attempt to learn about the normal travel patterns for that vehicle so that predictions can be made about ...
0
votes
0answers
25 views

Yandex Navigator / Maps - Determining user location

Kindly redirect me to a more appropriate forum in case there exists one. I am an active user of Yandex.Navigator App (available for all kind of mobile platforms). Whenever I open the App, even though ...
1
vote
2answers
55 views

Where can I find the coordinate system used by GPS

How do you determine which geographic coordinate system is used by a GPS device? For example, my Garmin GLO is outputting NMEA data with lat/lon. What system is represented by those lat/lon values? I ...
3
votes
1answer
49 views

How does GPS Unit make sure that they have the same time reference from GPS Satelites?

I've been reading readers about GPS to find how GPS work, but one thing still bothers me. To calculate distance from gps unit/receiver to gps satellite, it uses the difference between radio signal ...
0
votes
1answer
76 views

Getting GPS coordinates perpendicular and parallel to AB

I already posted this question here And I got the solution thanks to Fang but the problem is that the coordinates I need to use are GPS coordinates and apparently GPS needs a different formula than ...
0
votes
2answers
37 views

Deployment of Zeno Field 3.11 in windows 8.1

Is it possible to install Zeno Field 3.11 in windows 8.1?
2
votes
4answers
135 views

Where to license non-automotive POIs for France, Spain and Portugal?

qualified POIs are needed for a commercial project - should cover broad out-of-car usecases (not needed: parking, gas stations). Could be commercially licensable data or derived from national geodata ...
5
votes
1answer
396 views

How to connect particular sets of points with (poly)lines?

I think my problem is quite easy to be solved by the most postgis-users, but i am a bloody beginner: i have a timestamped point-table representing GPS-tracked places of different cars. To distinguish ...
2
votes
1answer
67 views

How to find if two gps tracks were from the same trip?

Given I have gps tracks from many users running or hiking, how can I find out who were running together? In other words, which algorithms are there to find out who were in the same party? Haven't ...
12
votes
2answers
474 views

Why does GPS altitude jump sometimes?

I am currently developing a little application in Android which uses GPS. When i click a button i start to record a "track". If i walk around i save my position every second into a file. This works ...
0
votes
1answer
39 views

Benefit of DGPS for relative accuracy and speed measurements for receivers close-by each other

Consider that we are interested only in the speed and relative position accuracy of GPS receivers (i.e. their absolute try position on earth is NOT important). These receivers are all in a 90m x 90m ...
2
votes
1answer
74 views

calibrating vector line in qgis

I have loaded GPS points into a QGIS vector layer. I also imported a vector line from a dxf file which doesn't have georeferencing. I would like to fit in line geometry between the GPS points - how ...
1
vote
0answers
91 views

Available modules/products for GPS+IMU sensors shipped with sensor fusion SW?

Are there any solutions/products (modules) in the market that integrate GPS and IMU sensors that come together with the sensor fusion algorithms (Kalman filtering etc.) implemented and ready for use? ...
2
votes
2answers
164 views

How can I transfer waypoints and tracks from Base Camp into QGIS2.6?

I'm working on transferring all my field data from Garmin Base Camp onto QGIS. This is an attempt to overcome the learning curve from basic trail GPS mapping programs to the real thing. I'd like to ...
9
votes
2answers
185 views

How to detect traffic incidents in set of GPS traces?

I have a large database of gps traces (long, lat, timestamp) and would like to see if I can detect when congestion occurs on roads from that data. Any ideas or pointers on good algorithms to use? ...
0
votes
1answer
43 views

What does 'Course Made Good' in NMEA string mean?

I was looking at some GPS data that a client sent me. It has lines like this: $GPRMC,183123,A,1725.4170,N,07825.4779,E,37.80,297,161214,, I was looking at http://aprs.gids.nl/nmea/#rmc, which says ...
0
votes
1answer
121 views

Terrasync COM Port Unavailable

I have a Trimble GeoExplorer Series GeoXM that runs Windows PocketPC version 4.2 (Built March 15 2004 for a bit more resolution there). Lately when the unit has been out on a job it will periodically ...
2
votes
1answer
372 views

How to interpolate GPS data correctly?

I'm working on a project that involves using linear interpolation to fit lines to lat/lng points. I'm pretty new at scientific programming related stuff, and I was wondering if people could steer me ...
0
votes
0answers
97 views

Store GPS trace with timestamps, then interpolate location by time

I'd like to: Load a 1-second interval GPS trace (not GPX) into PostGIS Then query the table at sub-second accuracy (about 5Hz), and get PostGIS to interpolate the location by time. Is this ...
4
votes
3answers
545 views

Wildlife surveys using tablet and GPS, import/export to/from ArcMap

I've found some info about this on a previous post (Advanced android app for mapping and GPS logging), but it didn't provide enough info, I'm hoping some other tech experts can help! I have a tablet ...
4
votes
3answers
1k views

Mobile, Offline viewer for geographic data

Currently, field crews consumer geographic data via laptop (no internet, no gps). ArcReader. I would like to get them shapefiles (or some derivative of a shapefile) on a mobile platform (smartphone) ...
2
votes
3answers
4k views

Can *.ssf files from Trimble GPS be imported as features to display in ArcMap?

I have not come across *.ssf files before but I believe they are a Trimble GPS binary format. Someone has asked me if these files which he thinks have line/poly features can be imported for display ...
19
votes
6answers
4k views

How to create a polyline-based “heatmap” from GPS tracks?

This winter I am planning to track my downhill skiing/snowboarding using a GPS. Most of my riding will occur at the same resort. I would like to be able to create a sort of "heatmap" that shows the ...
0
votes
0answers
13 views

Simple app for generating polygons - offline solution [duplicate]

As the title says, but capable of importing raster, and exporting the vector to a compatible format to QGIS. The vector-layer needs attribtutes as well and has to be GPS-orientated. IOS or Android. ...
1
vote
1answer
40 views

Use of satellite-based augmentation outside of base station coverage

In certain locations GPS units can recieve an SBAS correction signal (WAAS, EGNOS etc) but are outside the coverage area of a base station. For example, EGNOS signals can theoretically be recieved in ...
2
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0answers
52 views

About Timestamp in Geotagging

I'm on my reasearch for GPS and sensors integration. I've just wondered that to integrate between GPS and camera you need time offset synchronize which called as a timestamp. But how does software ...
0
votes
0answers
50 views

How to average GPS tracks?

I have GPS data - point cloud in a shapefile. Now I want to average this data and get on output a single GPS track. Here I found images but can't find algorithm. Maybe gdal or postgis can do it? Any ...