FlightAware Discussions

Setting Site Location - Error with Map location

Hi,
New here and only just got my PiAware up and running.

I want to set my site’s location but when I try to use the Configure Location tool the map display is blank (tried to access it with Chrome and Safari), I wonder if this feature not working f
or everyone, or just me.
I have manually set the lat/lon and antenna height but it would be good to confirm the location using the map.

Thanks,
Kieran

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Can confirm the bug.

This site comes in useful: https://www.mapcoordinates.net/en

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I always used my phone’s GPS. Apps like GPSTest can show the coordinates exactly.

For this i would always need to go outside as GPS is not working indoor.

So using a map is more comfortable :sunglasses:

Don’t you have windows? :slight_smile:

I use a free Android app called GPS Status. I routinely receive 13 of 17 sats from inside my condo comm closet that has no windows. That said, the Galaxy S 9 gps position does not come close to matching the position on my stand alone gps receiver.

Very helpful URL.
I was using Google Maps but that doesn’t give height AMSL, so not as accurate as your link.

The GPS on a smartphone is OK but not accurate.
Also, GPS itself is not as accurate as many think.
For example, this week there are 2 satellites (out of an operational constellation of 31 sats) offline which does lead to some periods of the day when GPS gives some quite large errors.

I’d be tempted to trust a good map source for a more accurate lat/lon/elev fix.
Kieran

Your phone has an error of max 5-12 meters. That’s more than MLAT needs.
I am getting 5 meter accuracy right now, from my window, on my Galaxy S10.

Plus, you get a fix from US, Russians and EU satellites. That’s more than plenty.

I do, but still need to get off from my sofa and walk over there :wink:

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That’s the accuracy of your phone. It does not mean that it’s 100% accurate.
But good enough for getting the data documented.

Most of the maps rely on GPS data, so it doesn’t matter if you use a map or your phone

Most mapping applications will use STRM data which is then corrected to WGS84. WGS84 just happens to be the same reference datum used by GPS.

I don’t think that your S10 is using multi-constellation GNSS for a navigation solution, it is just using GPS. If you look at the sats in view it is only listed the GPS ones.
The GNSS receiver on the phone can see GLONASS and Galileo but probably not using them for a nav fix.

Hopefully it won’t be too long before our smartphones can pickup SBAS (WAAS in USA, EGNOS in EU) too.
Also, with the Chinese putting more Beidou (aka Compass) satellites into orbit we will have an embarrassment of choice when selecting a GNSS for nav.

5-12 meter accuracy is what you will see under ‘normal’ conditions but 12m is by no means a maximum.

For my day job I run a GPS accuracy and integrity (RAIM) prediction service which is used by the airlines - almost every day there are places around the world that get some time periods when GPS accuracy is pretty poor.

I’ve got macOS, have to run Windows in a VM! LOL

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We have also GPS with much better accuracy in our topo survey team, using L2 in code-less mode. They have to set the station running for two hours before they can do any measurements. I don’t know what will happen after 2020, maybe L5 will be operational…

Anywho, that precision is not needed by MLAT. The calculations are not near this level of accuracy.

Does your survey setup allow you to use SBAS too? Not sure what part of the World you are in.
However if you already have dual-freq setup that will give very good accuracy.
Also, with dual-freq your survey setup will be less susceptible to propagation delay caused by ionospheric interference.

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You don’t need centimetric accuracy for your receiver location. Within a couple of metres is perfectly fine. You can also mitigate the random error in gps with time - taking averages over a longer period of time will get you a pretty good position. There’s probably an app that can do it.

If you use a (relatively modern) proper GPS receiver rather than a phone, it will likely have WAAS or EGNOS support, which uses a geostationary satellite to add some correction data for atmospheric conditions. You can get a position accurate to 1-3m with that.

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I had the same problem. Here’s how I solved mine. I used Google Earth Pro to determine my position, but was inputting the wrong units. You need to be using decimal degrees, or your off, in my case by several KMs. How I proved it was to enter the coordinates into Google earth That I was using to program the receiver. As soon as I entered the right units of measure my setup map appeared. Hope that helps. It would appear the receiver checks surrounding stations and if the timing is out the MultiLats will not allow the map to be displayed. That’s just my thought on why.

Suddenly nobody has an smartphone to see the real coordinates??? To me is scratching backwards with Google Maps… or any map for that.