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

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11
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10answers
4k views

Need a Benchmark GPS Trajectory data-set? Anyone?

I'm looking for a benchmark GPS data set, available for research purposes for free. I've found GeoLife GPS Trajectories dataset from Microsoft Research but I find it a little incomplete. What I need ...
0
votes
0answers
58 views

How to create speed maps with gps data

I am looking to create a speed map from gps data, one of the problems is that the data overlaps due that the road is a track. How can be the best way to plot this map? I have Qgis and ArcGIS options ...
1
vote
0answers
46 views

How can I calculate times with gps data using random points on the track? [closed]

I have GPS data from a car that is circulating all the time in a closed circuit. I need to put a few points along the route, about 3 or 4 and calculate the time it takes to get between points. These ...
1
vote
5answers
3k views

Solutions for uploading maps to GPS (forestry maps: roads, trails, hydro, polygons)?

I'm using a QGIS 2.2.0 Valmiera on a Windows 8.1 system Desktop. I'm a forester and I would like to have a cheap solution to load maps into the handheld Garmin 60, 62 or 64 series GPS. Free would be ...
1
vote
1answer
146 views

GPS tracking times

I have a GPS data on a closed road, where the cars riding laps, and I want to know how long takes to do 1 lap and also I want to add some points to calculate how long takes in specific sections. One ...
1
vote
1answer
560 views

GNSS planning online vs trimble planning 2.9 software

Why using the same parameters GNSS planning on-line and Planning 2.9 Trimble show me different Dilution of precision (DOP on the graph)?! Which program is better mission planning solution for GNSS ...
1
vote
0answers
175 views

Post-processing GPS Satellite Measurements

I am working on a system that reports its location to a server using very little power. In order to achieve an extremely low power usage, I am avoiding having to download both the almanac and the ...
1
vote
0answers
23 views

Filter GPS tracks to determine “Moving Time”

I am working with GPS tracks of outdoor activities, think cycling, running, hiking. These activities often have "rest periods" where people take a break, wait at traffic lights, or just stopped their ...
3
votes
2answers
224 views

QGIS Real-Time Vector Layer Creation

QGIS is running on my Windows PC. I have a CSV file on my PC that is remotely updated with values of a raspberry pi's GPS position and some wifi-status readings. Is it possible to create a vector ...
16
votes
6answers
3k 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 ...
30
votes
6answers
2k views

Does an earthquake affect GPS?

There are news reports saying that the Sendai earthquake a couple days ago has shifted the earth on its axis and moved the island 8 feet. Last year, there were similar reports with the earthquake in ...
7
votes
2answers
5k views

postprocessing GPS coordinates with RINEX data to improve precision?

Im doing some mapping for OSM in my region and I am curious if the precision of tracks from a GPS Receiver can be improved if they are post processed with RINEX data. The tracking is done with a ...
2
votes
0answers
45 views

Convert xyz coordinates to lon/lat to calculate height change GPS time-series data [duplicate]

How can I convert the XYZ coordinates in Lat, lon to calculate height in metric system? XYZ ascii site YYMMMDD yyyy.yyyy __MJD week d reflon _e0(m) __east(m) ____n0(m) _north(m) u0(m) ____up(m) _ant(...
2
votes
2answers
430 views

In hyperbola model of how GPS equations are solved, why do 3 satellites give only 2 hyperboloids and 4 satellites only 3?

The Hyperbola depiction of how the GPS equations are solved: From several psuedoranges measured at the same time, we can calculate the (absolute) difference in the distances between us and these GPS ...
2
votes
1answer
109 views

Importing xyz text ascii GPS time-series for velocity visualization using QGIS?

How i can import text ascii xyz gps time-series in QGIS for velocity visualization? Example xyz MLBU 07SEP17 2007.7098 -0.119998752351520E+07 0.626106994328102E+07 -0.199557178074915E+06 0....
2
votes
0answers
36 views

Why time differs between gps and ntp exactly 90 seconds

EDIT: This question can be closed due to figured out the problem was in the NTP configuration. While the gps device is no gps data received, gps device is send gps time to server as zeros ("...
0
votes
1answer
195 views

Rounding Coordinates

If you want an accuracy of seven digits, should you then round to that value or simply just cut the numbers after that? Example: 51.1936137567 to 51.1936138 or 51.1936137567 to 51.1936137
2
votes
2answers
3k views

What class/types of smartphone chipsets support GPS, A-GPS, GLONASS AND have extended kalman filtering?

I've been testing several Android phones (all running Android 4+) Sony Xperia T, Moto G, Nexus and HTC 1 which are all giving decent tracks (all of which use GPS/GLONASS) However we are also using ...
0
votes
0answers
25 views

Live GPS tracking with both ping script

That's a professional context : During a travel between two train station, I would like to use the live tracking and analyse the network performance (access by Wifi & 3G/4G ). I would like to ...
1
vote
0answers
44 views

Turning QGIS Map into real time GPS for phones?

I'm attempting to create a map in QGIS for use on a website that will allow users to navigate pathways in a park (i.e. choose a desired location, and be shown directions). I'm done with the map (...
1
vote
1answer
462 views

How to improve accuracy or extrapolate missing or bad GPS points

Is there an easy to use freeware tool to postprocess my location data, in order to correct 1) location errors (or improve accuracy not based on differential GPS correction) and 2) deal with missing ...
2
votes
1answer
279 views

Calculate road distance between GPS points

I am working on tracking system that track location of vehicles on the map and tell their total distance from the beginning till today. I have device_id, timestamp and GPS location in the table like ...
4
votes
3answers
5k views

Measuring polyline using either QGIS or ArcGIS Desktop?

I've collected a bunch of GPS polylines (WGS84). What is the easiest way to measure the length of these lines in KM using QGIS or ArcGIS Desktop?
4
votes
4answers
5k 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 ...
0
votes
1answer
52 views

Connect a Garmin and fetch GPS stream

I own a Garmin Oregon 600. I know that it has some communication capabilities, but I have not found on user guide how to use it. Does anyone of you know how to connect this device by USB/Serial in ...
4
votes
2answers
190 views

Road segments reconstruction from GPS trajectories

We have a 10,000 base of vehicle mounted moving devices which report their GPS position on a time based schedule. All that data is currently being stored in our database for several business related ...
0
votes
0answers
63 views

GPS coordinates of a point between two known points

I am looking for an algorithm for finding GPS coordinate of a point on a straight line defined by say points p1 and p2 at distance r from p1. GPS coordinate of p1 and p2 are known. I searched a lot on ...
0
votes
0answers
90 views

Switching maps when zooming with Garmin GPSMAP 64s

I am using two different maps on my Garmin GPSMAP 64s, the Garmin GB Discoverer 1:50k map and the Talktoaster (OSM data based) map. As I am sure everyone knows, the Discoverer map looks rubbish when ...
1
vote
0answers
35 views

Find Minimum Bounding Box for a set of coordinates [duplicate]

I am working with GPS tracks (lat/lon values) and my goal is to compute the minimum bounding box for a small geospatial library I am working on. The datasets are not huge, maybe a couple of tens of ...
5
votes
1answer
470 views

Sub-meter Bluetooth GPS units and ESRI Collector App

We have been using Trimble XT/XH for years now, but we are at a time when we need to upgrade and do not want to drop another $8000 for another Trimble that only causes us headaches and not very user ...
0
votes
0answers
24 views

Valid Range of Geoidal Separation in GNS and GGA sentences

I haven't seen any information about valid ranges of geoidal separation in GGA and GNS sentences. I am using Nema Studio Simulator to simulate GPS receiver. In there Geoidal Separation can be set to ...
24
votes
5answers
40k 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 ...
11
votes
4answers
3k views

Bluetooth GPS to Smart Phone

Has anyone had any luck intergrating a GPS unit with your Smartphone? Looking to gain sub 5m accuracy. Ideally would like the phone to just use the better gps reciever when it is connected. This ...
1
vote
0answers
21 views

Is there any standard or source of information to check for valid ranges and accuracy of each information conveyed in NMEA format ?

Currently I am reading IEC 61162 Nmea 0183 standards document. In there there is not information about valid ranges of some values or precision of data fields in nmea sentences. Is there anywhere that ...
5
votes
5answers
304 views

Detecting and fixing outliers in a GPS trajectory

I need to find an algorithm or method that can detect outlier latitude longitude points in a trajectory during post-processing, which can then be fixed (brought back into the trajectory's path based ...
3
votes
1answer
84 views

How to generate missing points in GPS trajectories?

I have some GPS trajectories that include gps locations recorded on variable frequencies (every 1 min ,5 min , 20 min,etc.)using a geographic projection WGS84. In my work, i need a fine-grained GPS ...
11
votes
2answers
8k views

Low-cost centimeter-level accurate satellite positioning (GNSS/GPS) [closed]

I am looking for a low-cost (< US$500) GNSS/GPS setup with a centimeter precision without much HW hacking. I am not able to produce my PCB or do any soldering (though I would do that if there is no ...
3
votes
0answers
186 views

Import GPS SINEX (for velocity analysis) into Sarscape or processing with others software

I try to import GPS snx. into Sarscape 5.2 (use GPS Import tool) and getting error 115) ) gps_type : [sinex] 116) ) generate_kml : [OK] 117) ) generate_shape : [OK] 118) ) ...
1
vote
2answers
57 views

Matching Street names with GPS data?

I have a list with over 10000 street names and places. These street names indicate where Radar Speed controls are located in Germany. I Need to have a map, where those Points are tagged. I did this ...
1
vote
1answer
45 views

Is OpenStreetMap suitable for me?

I'm planning to create a map with GPS and routing support as well as other custom features for my local area. It will be for a commercial usage. I'm okay with showing OpenStreetMap logo in my app. Is ...
1
vote
0answers
45 views

Correctness of Measurement

I tried Google, but the questions isn't that easy to put in Google, so I haven't found anything about this. I am making a database with different locations (latitude and longitude). For this I have ...
1
vote
1answer
77 views

Calculating emissions from points in road network using ArcGIS for Desktop?

I have GPS data (X,Y, speed, CO2 and fuel consumption) for one truck for one trip. I want to import them in ArcGIS and to join them with the road network (map matching). I was thinking of applying "...
0
votes
0answers
34 views

convert a gpx file to a feature class loses ident field

Using the ArcGIS 10.3 gpx to feature tool (GPX To Features (Conversion)) the "ident" field is lost in the translation. DNR Garmin is an option but has limits to the number of points it can process ...
2
votes
1answer
53 views

Accuracy calculated by GPS

I found a lot of pieces of an answer to this question, but no complete and good one. How does a GPS System calculate it's own accuracy at the moment? Where does it get the known position to ...
1
vote
0answers
23 views

Navigator for ArcGIS integration with a laptop via bluetooth

Does anyone know how to integrate Navigator for ArcGIS with a laptop via bluetooth to display location information/point locations from a web app residing on a laptop? Or can I just call the ...
0
votes
1answer
42 views

Implementing WaterML2 output in my web service

I'm trying to implement WaterML2 output for my sensor network webservice. Currently I report sensor data where the data includes IDs for each sensor, time of sensor readings, units and, optionally, ...
1
vote
0answers
27 views

Magellan GPS stops recording data in suspend mode [closed]

Currently having a problem with my Magellan Explorist 510 GPS unit. After I start recording the track on the unit, after some time, it just stops recording data in suspend mode (which should turn ...
1
vote
2answers
79 views

Collector blue accuracy ring- what does it show?

What, definitively, does the blue accuracy ring show in Collector. In the field it always seems too large to represent the accuracy that the GNSS app is stating (ie 50cm – 1m). The blue ring seems to ...
6
votes
2answers
810 views

Map-matching GPS points to the road network!

I am quite a newbie in Postgres and Postgis so please be simple and clear :) I am trying to do a simple map-matching (or path-inference if you wish) of some GPS points. I am using postgres(postgis). ...