Global Positioning System (GPS)
0
votes
1answer
298 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 - ...
1
vote
1answer
1k views
Difference between Garmin eTrex Legend HCx and eTrex 30?
I have used etrex Legend HCx a lot and been satisfied. Now I've seen etrex 30 just for a while and it seems to me that the Legend is much more user friendly, good old menus with a lot of ...
3
votes
2answers
278 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 ...
12
votes
3answers
449 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 ...
3
votes
2answers
2k 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 ...
2
votes
0answers
94 views
How to configure various client applications to display AVL data?
Given x number of GPS units transmitting NMEA formatted strings back to a server (xxx.xxx.xxx.xxx:xxxxx) is there a way to listen in on the traffic and parse NMEA formatted strings for display on a ...
10
votes
1answer
367 views
Overview of GPS tracking system technologies
Background: I've been asked by a friend to estimate the cost of setting up a GPS tracking system for a small fleet of buses, so we can do real time reporting of bus locations via a webmap.
In my ...
4
votes
4answers
1k views
Connecting GPS to ArcGIS via USB
Is there a way to connect a GPS to ArcGIS via USB? At the moment the GPS extension only appears to support comm port connections. It would be good to know if a USB connection can be made, then perhaps ...
5
votes
1answer
180 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
828 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 ...
3
votes
1answer
844 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
votes
2answers
673 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 routepoints that are impossible because it would require acceleration that the vehicle can not achieve. Are there good ...
0
votes
1answer
216 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
167 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 ...
4
votes
3answers
1k views
GPS post processing - Differential Correction
I have a large set of collected GPS points that I'm pulling into Arcgis from SQL and creating an xy event layer to then map them. The fields for the points are as follows: recorded, lat, long, ...
3
votes
3answers
423 views
GPS drift during the receiver is stationed
I have developed a GPS Tracking device it is working fine when the receiver is in motion, when it stationed in a position for couple of hours i get some drift for around 10-15meters. The receiver send ...
2
votes
1answer
728 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 ...
4
votes
1answer
3k 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 ...
0
votes
1answer
90 views
Programs to log NMEA on Nomad 900?
I am interested in logging NMEA data on a Trimble Nomad 900. Unfortunately the SatViewer records a maximum of 64,000 characters, too little for my application. I don't want to have to purchase ...
8
votes
0answers
294 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 ...
13
votes
4answers
2k 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 ...
12
votes
2answers
4k views
What is the difference between triangulation and trilateration?
Looking around I noticed that many people exchange the terms (tringlulation and trilateration) for the same sense.
What's, actually, the correct sense of Triangulation and what are the differences ...
12
votes
5answers
2k 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
96 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 ...
3
votes
1answer
647 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
638 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 ...
7
votes
11answers
1k views
Logging GPS and Accelerometer Data - Device Suggestion?
I am looking for a device that can track my location (lat,long) and speed all day long. Perhaps, I need GPS and accelerometer data bundled together.
What I want to do is to log my daily activities. I ...
4
votes
1answer
2k 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
242 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
220 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.
3
votes
2answers
402 views
Alternative to Terrasync for Trimble Windows Mobile unit
I have a number of Trimble Nomad 900 series devices and am currently using TerraSync.
TerraSync does the job, but are there any other alternatives out there that would be even simpler to use?
...
1
vote
0answers
185 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 ...
8
votes
3answers
2k 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 ...
5
votes
4answers
447 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
3
votes
1answer
173 views
How to export offsets from Trimble Rangefinder?
I already asked this question at http://www.rpls.com/forums/viewtopic/8/1276880, but didn't get any answer so far. Maybe here someone can help...
I have a question about the use of Trimble Products. ...
15
votes
6answers
755 views
Sources of realtime spatial data
I'm trying to set up a demo that serves up live spatial data, but am having trouble finding any suitable example data sources.
Ideally I'm looking for something that updates every few seconds; either ...
23
votes
6answers
3k views
Why does GPS positioning require four satellites?
I have a question on the GPS positioning algorithm. In all books I've read for 3D positioning we need four satellites, and I don't understand why.
We need to calculate three variables: x, y, z. We ...
10
votes
2answers
307 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 ...
14
votes
10answers
563 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 ...
3
votes
1answer
195 views
What is the DNSC08 Mean sea surface model ellipsoid based on?
Does anyone know what Danish Space centre DNSC08 mean sea surface model uses as the reference ellipsoid? there is no meta data on the web site:
...
0
votes
1answer
650 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
574 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 ...
2
votes
0answers
307 views
How to read a .GPB file in C#?
I have a .GPB file, I need to extract the common GPS data from it but I don't find a clear structure that specify the contents of that file.
as a sample record from file
00000260 02 11 A9 61 E7 96 ...
1
vote
1answer
110 views
Finding intermediate points and speed over a segment
I have a dataset which is in the form of ( Time , Car ID, Speed at that moment, Lat,Long) and I need to do some machine learning on the data to answer the following questions :
Best route from ...
1
vote
2answers
566 views
How do I download tracks from the GARMIN GPSMAP 78 usin DNRGarmin?
I have been able to download waypoints to DNRGarmin by accessing the GPX file. However, I have only been able to view waypoints.
How can I download tracks?
2
votes
1answer
791 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:
...
7
votes
4answers
436 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 ...
4
votes
1answer
193 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.
...
4
votes
1answer
679 views
Point interpolation in route
I have a set of GPS coords with X,Y and Course. I need to interpolate additional points based on the course of each point. It would be a simple line intersection based on lines drawn using the 2 ...
3
votes
6answers
1k 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 ...
