A-GPS not working (v1.8)

Just updated to v1.8 and it seems, GPS it not working at all.

When I enter the A-GPS Settings, I see this hint under ‘Mobile Networks’:

“A-GPS needs to access the mobile network via data connections”

Weird. I have WiFi disabled and Data Connection is enabled. Should work. No idea why.

Also, the Device Manager is unable to locate my Fairphone anymore.

Any ideas? Not sure if it is a bug or if the update to 1.8 reset some of my settings?

Thanks for any advice,
Michael

2 Likes

This… would be a definitive show-stopper for me.
what happens when you try in presence of a reachable wifi?

Indeed, it’s bad. The same goes for WiFi, GPS gets no fix, nothing happens.

"[quote=“michaelheuberger, post:1, topic:3382, full:true”]
When I enter the A-GPS Settings, I see this hint under ‘Mobile Networks’:
“A-GPS needs to access the mobile network via data connections”
[/quote]

If I check on my Fairphone I get the sentence:
"A-GPS needs a wireless data connection to acquire the assistant data that may cause extra fees. Are you sure to turn on the A-PGS? "

So in my humble opinion it’s only a warning that there could be extra fees involved.

Why did you disable WIFi?

Simple answer: I disable WiFi when I am outside, away from my home or office to save power.

GPS is supposed to work when data connection is on, regardless of the WiFi status.

The GPS will work without WiFi. The phone is only giving a warning that GPS uses a data connection and therefore will cost you money when you can’t use WiFi.

Yep, I understand and knew that.

But GPS is still not working. What should I try?

The other app, GPS Test Plus, tells me, my fairphone has no GPS fix. And the Google Device Manager is unable to locate my device. I tried all combinations of data connection + WiFi. Nothing works.

Any clues?

You can improve your GPS.
Go to ‘SETTINGS’ (the button far left below on your Fairphone).
Tap on 'Location access’
Make sure that ‘GPS satellites’ are 'on’
Tap on the word 'GPS satellites’
Make sure that the box after ‘GPS EPO assistance’ is ticked on
Tap on ‘EPO settings’ and leave the box after ‘Auto download’ empty.
Make sure that the box after ‘A-GPS’ is ticked on
Tap on ‘A-GPS settings’ and only tick the box after ‘Network Request’ to on.
Reboot your Fairphone.
Now download F-Droid and install Fdroid on your Fairphon , here you can get apps where the most apps are Free and Open Source Software.
Then on your Fairphone you go to the app Fdroid and in the app search for FP1-EPO Autoupdate.
Download FP1-EPO Autoupdate. After the download run the FP1-EPO-Autoupdate, give it permanent Root access.
On this link you can find more information how to install.

Success

1 Like

Really? Before I try that, tell me why Fairphone isn’t fixing this? Why doesn’t the automatic EPO download inside the Fairphone kernel work?

I’d like to know the truth before I add more “mess” onto my phone.

[see this article][1][quote]The built-in EPO updater of the Fairphone (or other Mediatek phones) downloads the two EPO.dat and the checksum from an FTP server from Mediatek. However, the checksum is often calculated wrong by Mediatek[/quote]
[1]: https://gitlab.com/sn0b/fp1-epo-autoupdate/wikis/home

Thanks for explaining. If the EPO checksum isn’t calculated properly, why is nobody reporting this to Mediatek and is fixing the bug?

Why do you think nobody reported this to Mediatek?
Mediatek decides which bug gets priority and which bug not.

Okay. Two more questions: do I have to enable data connection to make GPS work? Or will it work with WiFi only?

GPS works with nothing at all if need be. What is at stake with ‘Assisted GPS’ is faster convergence.
A-GPS uses extra info which is the identity of neighboring wifi network names and GSM towers ID; this is what gives you the initial large location dot at startup (until enough GPS sats are catched).
How this extra info is fetched depends on what you allow: for EPO data, for instance, FP1-EPO Autoupdate will go fetching it only when on wifi, in order not to overspend. You also can cancel this and manually update every now and then, which basically should be as efficient.
But even without any data connection, you GPS will converge. Only, verrry slowly. Honestly, not fast enough to take the phone out in some street and know where you are (or else, find a square and wait :slight_smile: )

@Lidwien , The EPO download is now simply disabled and if you enable it in the settings there is no need to install FP1-EPO Autoupdate. We disabled EPO download because test showed that when this was enabled the time to first fix was about 45 seconds (in the open).

We also tested with AGPS “only” and with WIFI disabled (Here is a ratter bad quality video shot this morning http://dev.fairphone-open.com/keesj/up/AGPS_morning_test.mov )

@michaelheuberger there are a few things at hand

First of all if you use a GPS without any form of assistance getting a fix can take up to 12 minutes (the data about the exact location of the satellites is sent over the GPS signal and this can take up to 12 minutes).

EPO Download and AGPS (satellite data) downloads can be done over a data connection and over WIFI. But there is a big difference between EPO data and AGPS data. EPO data is valid for about 20+ days while the AGPS data only for something like 4 hours.

Testing showed that getting a first fix using EPO data is slow(± 45 seconds) compared to getting the fix over AGPS(± 15 seconds).

There is a lot of confusion about location data. AGPS can also directly provide the device with information about it’s current location. This is normally a global position that is not very accurate and it depends on the network what kind of data you get back (Wifi or 3G). This kind of positioning will at least provide a global location even when inside a house.

In my experience enabling the data connection and enabling APGS provides a decent (not great) positioning but when in a location where I have no connectivity I will enable EPO download beforehand.

keesj’s post describes my own gps experiences perfectly. When I first got my FP, I noticed that the only thing that actually worked better on my old and outdated HPC was the GPS function. I often had to wait 1-2 minutes for a fix, sometimes more (but never as much as 12 minutes, thankfully).
I do not use the GPS particularly often, but a fortnight ago (when still running the 1.6 version) I sat in my car and needed to find an address. I was surprised and delighted to find that the fix took no more than 15 seconds or so, and after a few more tests (also after updating to 1.8) it still works just as well.
I have A-GPS enabled, and also valid EPO data files installed using the invaluable FP1-EPO installation app mentioned above.

Height curves, covered distance, and walking/running speed registered by apps of the ‘My Tracks’ type is another thing, though. These data are seldom accurate. But I’m not sure whether FP hardware or software can be blamed for this or if it is simply a consequence of the limitations of the GPS technology. And personally I don’t care at all.

Are you suggesting that the following issue is solved?[quote=“Lidwien, post:10, topic:3382”]
The built-in EPO updater of the Fairphone (or other Mediatek phones) downloads the two EPO.dat and the checksum from an FTP server from Mediatek. However, the checksum is often calculated wrong by Mediatek
[/quote]

Because that’s the reason I use the Epo autoupdate from Fdroid.
For me a AGPS data which is only for something like 4 hours is not long enough.
That’s why I like the EPO data from Fdroid, which is valid for about 20+ days and I can update just at home using the WiFi.

1 Like

Yes, the download URL was moved from FTP to HTTP and it now is possible to download the EPO files without the additional software. You can go into settings->location access->Click GPS satellites and enable GPS EPO assistance.

2 Likes

To be clear about EPO: is EPO enabled slower because it couldn’t download recent EPO data from MediaTek or is it slow even when you’re up-to-date?