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Epic GPS - does yours work or not?

Epic GPS - does yours work or not?

  • Yes - works just fine

    Votes: 55 62.5%

  • No - I can't believe it

    Votes: 16 18.2%

  • Dunno - need more time to test it

    Votes: 17 19.3%
  • Total voters
    88
Took a +- 20 minute walk outside and had no issues with the GPS tracking my location. In fact I just checked in my top floor apartment and it was still able to pick up 8 satellites and pinpointed my location perfectly. I don't see any issues with the GPS on the Epic.
 
I think there's abundant evidence, as demonstrated by "GPS Test" and the signal levels reported by it, that the Epic4G's GPS hardware is *at least* as good as the GPS hardware in the CDMA Hero. What's missing is software behind it that implements every known best-of-breed hack and enhancement for making the best possible use of that satellite telemetry data in conjunction with data available from other sources, so it can quickly and robustly acquire a cold fix under marginal & challenging indoor signal conditions.
 
Bitbang3r said:
. Most likely, because HTC, Apple, and others own one or more key patents involved with those improvements, and Samsung declined to license them to cut costs.
Click to expand...

I find that to be purely speculative and unpersuasive. Although there may well be multiple software problems in the Galaxy S GPS stack, we do know from other threads elsewhere that there are core problems in the proprietary low-level drivers for the Broadcom GPS chip. Not only Samsung, but also Broadcom, are known to have been working on new firmware.

That chip, the BCM4751, is very new -- the latest and greatest in Broadcom's GPS product line. It should outperform its slightly older siblings used on iPhones. But not only does it not do that on the other Galaxy platforms, it cannot even match the performance of the very oldest Android, the G1, which uses another chipset entirely.

Samsung has not admitted that anything is broken, but has announced that it would "optimize" and test new GPS firmware -- at least for the Vibrant and Captivate -- in September. But for the Epic, Samsung seemed to go further, stating recently that the GPS had been "tested and validated." (But note that neither Samsung nor Sprint has expressly said that the new software got finished and loaded onto these early Epics in time for release.)

So there are two factual questions to be answered:

1) Does this version of the Epic 4G, as released, actually contain the latest updates from Samsung and Broadcom to all the drivers and other firmware?

2) Do those updates actually fix the GPS problem that has plagued other Galaxy S variants?

For some, there is a nagging fear that there may be hardware issues that are not amenable to firmware fixes.
 
Folks, there are 2 components to determine if a GPS is working.

1. Locking on to sats.
2. Accuracy of position shown.

It doesn't matter if you locked on to 8 sats if your location accuracy is 10+ meters. Can you folks please state how many locked sats and dimensional accuracy achieved in your post so we can have numbers to compare?
 
It works, not as well as it should, but better than I thought it might. We'll see if it is useful for navigation tomorrow.

Outdoors, with network triangulation disabled:

8 satellites locked, 8 in use, SNR was between 10 and 30 for all satellites.

Accuracy was at +/- 98.4 feet.

...

For comparison ...

An iPhone 4 using Motion X GPS reports 33 feet, and is certainly closer on the map than the Epic is. I believe Motion X GPS reports discrete accuracy "blocks" rather than infinitely variable values (I stand to be corrected), and they are something like 33 feet, 56 feet, 98 feet, 156 feet and so on. So 33 feet could be right on the cusp of rolling up to 56 feet.

A Garmin Rino 530HCx with just 3 birds locked reports +/- 55ft and with 8 locks comes down to 10 feet.

All tested in the same location.

NOTE: Do not test two powered-up GPS receivers in close proximity to each other (only have one unit on at a time) as they can affect each other.
 
Torq said:
Outdoors, with network triangulation disabled:
8 satellites locked, 8 in use, SNR was between 10 and 30 for all satellites.
Accuracy was at +/- 98.4 feet..
Click to expand...
thanks it is the 98' that raises a flag

I am getting an average of two less satellites, and 4x the inaccuracy (hdop), double the SNR, and visible walking position lag outdoors with the Epic compared to three other devices I am testing alongside (Touch Pro 2, Treo Pro and Evo)
 
Yes your heard it first.... twitter it, facebook ii, post it. blog it.... etc.... epic gps doesn't work.. I call sprint and it is a known issue with the phones.
 
One of the many Galaxy S GPS Fixes posted, called for going into the GPS settings and changing the acceptable accuracy for a satellite lock to 100'. I assume this would allow locks on more satellites quicker while sacrificing accuracy.

It would be interesting if someone would see if the stock GPS setting on the Epic has been set at 100 feet. If it is, Emgadget needs to be notified that they have been deceived by Samsung.
 
lescooper said:
One of the many Galaxy S GPS Fixes posted, called for going into the GPS settings and changing the acceptable accuracy for a satellite lock to 100'. I assume this would allow locks on more satellites quicker while sacrificing accuracy.
Click to expand...

Actually, we never knew what that setting did. (And that "fix" was not posted by Samsung, but by one of many quasi-ignorant users just pushing buttons they didn't understand.)

That setting, in a hidden menu, was just labeled "Accuracy" but entirely undocumented. We have no idea what its values represent -- whether they relate to some unit of distance, or some arbirtrary parameter or coefficient. The default value is 50. It is apparently related to another property called "Dynamic Accuracy," which is toggled on/off. Nobody knows what that does, either.

And, BTW, all that experience iis from other Galaxy S platforms, so we need to be careful extrapolating. It is apparent that at least part of the GPS software has been reworked somehow on the Epic, but we don't know any details. For example, there is a hidden system app called GpsSetup that does not exist on other Galaxy S variants.
 
I also ran GPS Test (paid version) on my Epic immediately after getting the phone, while on the way to work, and then again in the middle of the day while the phone was sitting in the desktop inside my single store office park building, and then once again on the way home. All the times I ran it I was able to quickly acquire a lock. Getting a lock inside took a little more time and it wasn't able to use ALL satellites it found - I assume they were below the set threshold for acceptability. I also would like to note that the SNR data given by GPS Test was FAR superior to that of the SNR I would get on the Moment. My average SNR on the Epic is easily 10-15 units higher than the Moment, and I didn't have much of a problem with the Moment's GPS getting a lock and function just fine either.
 
lescooper said:
It would be interesting if someone would see if the stock GPS setting on the Epic has been set at 100 feet. If it is, Emgadget needs to be notified that they have been deceived by Samsung.
Click to expand...

Mine is set to 1000ft with 180s timeout, which I haven't changed. The Moment was set to 1000ft with a 90s timeout. I'd be interested to see what my buddy's Droid is set to, maybe I'll grab it from him later.

You can check your settings by:
1. Open the dialer and enter: *#1472365#
2. Tap Misc Settings
3. Tap Set QoS

I played with these settings on my Moment quite a bit and never found that they made a difference. It did seem that when I set the Accuracy Threshold really low, like 50-100, that I had a more difficult time getting a lock. If this wasn't just by chance that I was in a bad spot to get a lock, I just assumed that those numbers are part of a the GPS accuracy algorithm and the lower the number, the more picky the GPS system would be in choosing which satellite data to believe. But that is just a guess...
 
Bitbang3r said:
I tried it with a coworker's Epic4g a while ago. IMHO, it looks like it has a decent radio & antenna, but depends entirely on satellites for ephemera data. I'm basing that on the fact that I left the GPS trying to get a lock indoors for nearly a half hour, about 10 feet from a window, with zero success... but when I walked outside, it locked in about 10-15 seconds, and instantly went from zero satellites detected to 10 or 11. And when I went back inside, about half of the satellites remained usable. I did the test using "GPS Test" (free version) from Chartcross (in Market). More importantly, I noticed that after I went back inside, the thresholds dropped down to the level that I believe is high enough to get a reading, but too low to do a successful telemetry download.

The moral: as soon as someone figures out a way to grab ephemera data from a thirdparty server somewhere, and rewrites the kernel module to make use of that data, the Epic4g's GPS will work just fine. In the meantime, if you're planning to use GPS in an environment with poor signal quality, get a lock outside first, then go inside. As a caution, though, it appeared to lose the GPS lock after I exited the GPS test app, allowed the phone to go to sleep, then woke it up and relaunched the app ~30 minutes later. So... it looks like Samsung might not be doing a very good job of caching the ephemera data once it's downloaded, or at least gives up on it and writes it off as invalid more aggressively than it really NEEDS to.
Click to expand...

How come HTC doesn't have this problem and samsung hasn't fixed it since the Moment days?
 
Okay so I thought my GPS wasnt working but then I went back to sprint and they said that radio shack personnel were retarted and they programmed my phone wrong. So I downloaded GPS STATUS after he was done and it immediately gave me longitude and latitude with wireless network and my location OFF. Thank you and have a nice day :)
 
bcrtj457 said:
So I downloaded GPS STATUS after he was done and it immediately gave me longitude and latitude with wireless network and my location OFF. T
Click to expand...
You can get that and still be off by 1000 meters.
It looks like Samsung has "fixed" this by simply allowing more inaccuracy which will fool some but not all.
 
Torq said:
8 satellites locked, 8 in use, SNR was between 10 and 30 for all satellites.

Accuracy was at +/- 98.4 feet.
.
Click to expand...
yes we are seeing incredibly bad SNR ratios and this points to a hardware attenuation problem. I am getting an average SNR of 19 outdoors no obstructions under clear skies. I am topping out at 29 on optimal sats at near perfect declination and azmuth, when other smartphones in simultaneous test are getting SNR of 35 to 45. At nominal outdoor conditions the Epic SNR is even worse

From what I can see the bad SNRs on the Epic are causing it to jump around on which sats it is using even while keeping the handset in one position.
 
Gremlyn1 said:
Getting a lock inside took a little more time and it wasn't able to use ALL satellites it found - I assume they were below the set threshold for acceptability. I also would like to note that the SNR data given by GPS Test was FAR superior to that of the SNR I would get on the Moment.
Click to expand...

I can't speek to the moment or captivate or any of the other Samsung GPS screw ups. I am testing against HTC WM and android, Palm WM and others and the

We can't use a baseline of the samsung captivate or moment with their known problems, that is kind alike using Bosnia as a benchmark for communal relations -- I am using popular mainstream smartphones that have working GPS and the Epic is looking very bad in compairson
 
I would consider mine working.

Here's a gps test I just did a minute ago inside my house. I had better SNR numbers when I was outside. Not really sure what to make of that 98 foot accuracy thing.

snap20100901_223025.png


Here's My Tracks mapping sample during highway driving

Track 3 - Google Maps
 
I don't understand those that say yes. Mine works but it does not work properly. Google maps and google earth shows my location to be 3 blocks off. This is with gps on. Freakin sux.
 
Hey, this is the same discussion as we have had in I9000 forum at XDA. It is a pretty pointless debate about some have some have not a problem. I would urge all that are not satisfied to return there phone and not think that all the phones are problematic. If you got 900 feet error after a normal 30 - 60 seconds you have either no clue of how to use it (load, memory line of sight etc) or have a faulty phone.

The most likely problem is the lack of linux kernel drivers to BCM4751 and that the rest of the implementation is not OK (at least in the lower levels). I have read in this forum somewhere, a reply or thread, of a guy that seemed pretty informed about the issue. Try to educate yourself by studying before you jump to conclusions and get a grip of what people with an insight in the area are saying.
 
As an update I got it to work accurately...with in a few feat..very sharp accuracy. I had the box checked which had "use wifi 3g" for location apps. I had to uncheck it. It still would not work correctly. But then I rebooted the phone, and after the reboot with that option unchecked the Google maps and Google earth worked perfectly(Very sharp accuracy). It took about 30 seconds to get a lock on...but I am very happy with it.

So to irriterate, you have to reboot the phone after disableing the use wifi/3g for locating apps.
 
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