Questions tagged [gps]
This tag refers generically to *any* space-based satellite navigation system that provides location and time information.
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Calculating GPS "satellite view" from ground points as proportion of sky traversed by satellites and unobstructed by topography
I'm a wildlife biologist trying to conduct a habitat selection analysis for GPS collared animals in western Washington State. There appears to be greater GPS error and more missing locations in areas ...
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Use QField with Bad Elf device/external GPS/specify GPS
Does anyone know if you can use QField with an external GPS Bluetoothed to the tablet that you are using… specifically a Bad Elf? Wondering if there are settings in QField app that lets you choose ...
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Seeking a bike GPS traces data set [closed]
I am looking for a collection of publicly available GPS traces, collected using bikes. Any suggestions if there is such data set?
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Making the coordinate trace looks more smooth without road network
We have a lot of coordinates generated by GPS and UWB devices for different users in our system. For a given user for a certain time range, when we tried to display their history trace(the yellow ...
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GPS lat/lons are off by about a mile
I have some old data from a flight that was done, it has a series of lat/lons for each datapoint. I've plotted these into Google Earth Pro and I can see that they are plotting about a mile west of ...
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QGIS z value, MSL vs HAE
I have been using Qfield to collect field locations (x,y & z) with a GNSS receiver. I can correct for the antennae height within the app (trimble mobile manager), so that that when QGIS records ...
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Different trend in elevation vs SNR in indoor and semioutdoor scenario
I'm recreating the some part of the experiment in this paper. The difference is I'm going to compare the SNR vs elevation in four different scenarios with clear sky condition
Basement
Indoor
...
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1400 grids in a shapefile that I want grid labels to display in trimble
So I have a grid boundary shapefile where I want to upload into TerraSync so I can collect data and know which grid I am currently in. Is there a way to do that in ArcMap or in TerraSync?
I found this ...
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Calculating ECEF position of gps satellite?
I am calculating the ECEF positions of satellites but the results are not what I expected.I'll show my code below but I'm following the gps specification(converting to radians from semicircles and the ...
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Way/tool to create an average of multiple tracks/polylines in ArcGIS
I'm still new at ArcGIS and have about 100 boat tracks taking roughly the same path. For my research, I would like to include the most used path/average of these. I attached a photo of all of my ...
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Feature Selection for Geospatial Vector Data Classification
The problem I am exploring right now is a binary classification problem about classifying road intersections into roundabouts or not roundabouts. The available input data consists of the GPS latitude /...
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Difference in variation of ECEF X and Y data from GNSS
I am logging ECEF data from multiple GNSS receivers and notice that there is always more variance in the the Y (latitude) axis than in the X axis of a scatter plot. Attached is a plot showing the ...
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How to determine if GPS coordinates fall in a defined area?
TLDR; I'm looking for solutions/algorithms to determine the following:
if an arbitrary coordinate (lat/lon) resides in the area of a circle resting on the surface of the Earth
if an arbitrary ...
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Continuously Operating Reference Station (CORS) or other passive corrections for "regular people"
My team is working on an autonomous car-type-mobile-robot-thing and we're looking to get some sort of corrected GNSS up and running for real-time high-precision positioning. A constant bias is fine, ...
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How to find the standard deviation in GPS measurement of latitude and longitude?
Let's say my GPS configuration is said to have a precision of 10 meters. I have taken this as the standard deviation in the GPS measurements. But the measurements that come from GPS are latitude, ...
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QField - get GPS Fix Status of captured point
I have a GG04 Receiver from Leica, using it with Leica ZenoConnect, NTRIP and activated MockLocation in QField, antenna in QField is set to internal. The Receiver is connected via Bluetooth.
We have ...
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No orthometric height from external device in QField
I have an GG04 Receiver from Leica, using it with Leica ZenoConnect, NTRIP and MockLocation in QField, antenna in QField is set to internal.
The Receiver is connected via Bluetooth, the shown height ...
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Convert GPS heights to AHD
My workplace is looking to replace our Geo 7X and TerraSync. We are looking to replace the Geo 7X with the Trimble DA2 and replace TerraSync with QField.
I'm currently trying to test QField and see if ...
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GPS latitude, longitude, elevation, and Total Station's Coordinates - can they be used together?
I have used DGPS to get the coordinates (lat, long) using UTM projection, and elevation (height above ellipsoid) for different points (set a). If I use one of the collected points location to setup ...
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Trimble GNSS Disconnected in TerraSync
I've been trying to get our Trimble up and running after a couple years of not using it. It will connect to satellites alright, but it won't show as connected in TerraSync. I've tried rebooting the ...
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How to map GPS coordinates to Potree Scene coordinates
I am trying to set initial view based on the GPS coordinates, but I can not understand which map projection Potree Scene is using?
Could someone please help me understand how I can map GPS coordinates ...
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Extracting Almanac using RTKLIB from ublox-M8N
I am fairly new to this. I have enabled the UBX-RXM-SFRBX command in the M8N and configured the M8N to output .ubx data, after which I recorded a .ubx file using u-center for about 13 minutes(which ...
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GPS coordinates conversion
How to transfer these GPS coordinates into conventional coordinates of long and lat? (the first column is East and the second column is North)
[1]: https://i.stack.imgur.com/ShuoH.jpg
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QGIS settings to generate a valid GPX file for Strava
I downloaded a GPX file from an activity in strava that had some errant points that caused the distance and elevation to be off that I want to try to correct. I imported the file in to QGIS and saved ...
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Why does an online GNSS satellite calculator give elevations ~15° different from what a GNSS app reports?
At https://satpredictor2.deere.com, satellite elevations above the horizon are given as, for example, 65° for GPS satellite 1, 38° for GPS satellite 3, etc. for my current location and time.
Using the ...
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HUGE latitude error from iPhone 4s
2015 April 15, I wandered around Little Rock, Arkansas, on bike, taking pictures with an iPhone 4s. Cloudy day, though some photos show shadows. Here are some of the metadata from three consecutive ...
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Distance Matrix won't consider elevation
Using QGIS Firenze
The Data is present in following Formats:
.gpx, .kml .csv. generated by garmin GPS.
lat, lon (In Degrees) and elev (in m).
There I have 70 Points. I can create a distance matrix or ...
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Extract Data from Corrupted TerraSync file, Pathfinder can't correct & won't open
I had an employee recording points for a project with a Trimble Geo XT 7 series receiver attached to a Zephyr 2 external antenna. The receiver went to sleep between collecting episodes. Upon ...
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Increasing GPS accuracy
I'm using a NEO-6M UART GPS unit and a Python script to record GPS data as latitude and longitude. However, it says accuracy 2.5 meters but I am not getting accuracy at that level.
Connected satellite ...
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Getting longitudes & latitudes from Chinese GPS location codes
I received a request about getting the longitudes & latitudes from Chinese GPS location codes, which I had no idea about, and they do not look like something convertible with those online GPS ...
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How to know the lane position on road?
I'm using Python to map match a given trajectory to a real lane of a road. However, the match is done in a random lane instead of the rightest lane. How can I choose to move the coordinates to the ...
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Lat/lon after moving x meters to a specified direction
I have recently been working with coordinate systems in Python with pyproj package. I'm facing the following problem: I know my current position from a GPS receiver as EPSG:4326 latitude/longitude ...
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Mobile phone GPS altitude decreases when measured from high rise buildings
I am using my mobile phone (Motorola G30) in which I had installed GPS Test app, to measure altitude. I am coming across something really weird. Attached is the screengrab comparing the altitude ...
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QField vertical grid shift files
I am located in Christchurch New Zealand and trying to get orthometric altitude to show and be recorded on the vector layers in the field. Ideally my manager wants this to be showing NZVD2016 R.L.s in ...
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Qfield 2.5.1 GNSS Bluetooth Connection Fail
As of the update to 2.5.1, I am no longer able to connect to my GNSS via Bluetooth and am presented with the following error "Scanning failed: Classic discovery cannot be enabled". The issue ...
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Transform ITRF2014 (2018.18) to ITRF2014 (2010.00)
I would like to transform a coordinate value from ITRF2014 (epoch 2018.18) to ITRF2014 (epoch 2010.00)
The ITRF2014 (epoch 2018.18) coordinate is: 5023564.4726, 1677795.7877, -3542025.8348
The GNSS ...
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Consistent error in GPS results - can I use this to my advantage?
I recently bought a SparkFun RTK Express GPS unit and I've been enjoying figuring it out. I can now talk geoids and ellipsoid models without sounding like a complete idiot.
There are several NGS ...
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Field Maps with ArduSimple GNSS
I was able to use ArduSimple RTK GNSS normally with Esri Collector. Now with Field Maps it behaves strange. I have an NTRIP subscription and my integration app Lefebure NTRIP works great. It can ...
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GPX File - Adding a Global Attribute That Applies to All Track Points
I am running a process where I am creating a GPX file from a GPS enabled video. What I want to do is embed the video file name into a GPX file attribute so that when I “click on” a GPX point, I get ...
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GNSS algorithms in Android and IOS
I am trying to determine what algorithms are used to determine location and speed in late-model Android and IOS smartphones. I am looking into merging the location data with higher frequency IMU data ...
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How does a receiver locate with more than 4 satellites?
If it takes 4 equations to find x,y,z and t, how does one improve the accuracy by adding 5th equation or does it reuse any 3 previous equations and recalculate with the 5th equation?
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I need a formula to calculate gml:pos to standard GPS coordinates
I downloaded "address points" data from geoportal and the coordinates are not readable for me.
<wfs:member>
<ms:prg-adresy>
<gml:boundedBy>
<gml:Envelope ...
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Is GPS data already filtered?
I was driving around in my car, with a GPS module on the roof. The data I collected is somewhat suspicious. The module I used is a standalone GPS module (L80-M39) integrated into a PiHat LORA-module. ...
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How can I calculate the midpoint between three points using accurate variables like Horizontal accuracy and HDOP
I have three (3) points with the following fields:
X
Y
Horizontal Accuracy
Vertical Accuracy
PDOP
HDOP
VDOP
And I would like to calculate the midpoint between these three points, using accurate ...
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Reverse trilateration / multi-lateration using BLE Beacons
I'm currently working on a proof-of-concept to work out the estimated locations (longitude and latitude) of outdoor beacons with unknown locations to begin with.
The solution will use a mobile ...
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Add point to layer with Coordinates from GPS stream
This is a real PyGIS beginner question.
I am trying to write a QGIS plugin and, very basically, would like to create a button that adds a point to a shapefile with coordinates from a GPS stream. What ...
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Plotting GPS velocity field and ellipse error in QGIS 3.26.1
I am a beginner in QGIS and I do not know how I can plot a GPS velocity field as well as ellipse errors (text file) in QGIS. How can I do this?
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Calculate nearest point in a orbital path to user (GPS)
TLDR: how do I go about determining the nearest point in an orbital path to a user's location?
Longer version:
This is gonna remain a bit vague, I'm uncertain of the terminology needed to ask/answer ...
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Calculate GPS elevation angle (Python)
I have two GPS points (Latitude, Longitude, Altitude) the distance between the two points is a maximum of 50 kilometers. How can I calculate the elevation angle? (I want to implement the whole thing ...
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Calculating and visualizing orientation of vehicle
I'm quite new to this topic but I would like to calculate the distance and heading between two sets of GPS coordinates. To do so I wrote a Python script which calculates the geodesic distance using ...
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