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All Things GPS

Did JI5 fix your GPS?

  • Yes, totally fixed my GPS!

    Votes: 15 35.7%

  • No, still having problems with GPS!

    Votes: 21 50.0%

  • Worked at first, then performance declined once again!

    Votes: 6 14.3%
  • Total voters
    42
krichek said:
Hopefully there is a GPS expert out there that can take this data and figure something out. Meanwhile, in no particular order here is what I Found:
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Okay what I personally can confirm is that my GPS works best at night, I would say around midnight also. Now if the theory is that the vibrant picks up a gps signal only on certain satellites that are in orbit, then the vibrant should technically pick up a strong signal twice a day, because the gps satellites orbit twice around the earth for each full rotation of earth. this would mean that there should be two blocks of time which the vibrant should work, because these satellites would go over your area twice in a 24hr period. So this is where there seams to be a problem, because that should mean your vibrant should work at midnight and die off from there, then be optimal again at 12 noon, and slowly die off from there, and pick up again at midnight. Sadly, I get virtually zero locks around 12noon. The locks only pick up around midnight which is odd.

also is your friend 10 miles away or 125? you said 125 in one post, the 10 in another, thats a big difference, may make a difference in your calculations.


Also, I was very very confident that the GPS issue is software based. However, some Epic owners are reporting poor accuracy. I'm starting to lean towards hardware issues
 
w_bovine said:
Egad...if that's true it's a catastrophic blunder on the part of Samsung. Hard to fathom really. Nice work krichek.
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I suspect that some satellites are never in view for certain parts of the world. Say the satellites that orbit the equator?

I believe that some satellites are only military as well, which could be why some are not used by civilian applications. So, with these restrictions and the fact that half of the satellites will be on the opposite side of the world at any particular moment, would leave only 10-15 satellites in view at any given time.
 
Okay lets test this orbit theory. I'm using an HTC spartphone and a Samsung Vibrant to see if the satellites in view and in use change as the satellites orbit around the globe.

Date 9/1/2010 Time 3:52 PM Los Angeles, California
HTC Phone: 11 sats in view, 8 in use
Sat numbers in use 2, 4, 9, 10, 12, 17, 27, 28

Vibrant:Same 11 sat numbers in view, zero in use

Quick update. 4:13 pm.. sat number 5 and 30 have now popped in view of the vibrant. Sat 30 has also popped in view of the HTC phone, but not sat 5.

I'll update in a few hrs, lets see if the sats in use change as they orbit around the earth.
 
w_bovine said:
Egad...if that's true it's a catastrophic blunder on the part of Samsung. Hard to fathom really. Nice work krichek.
Click to expand...


Thanks. So far it has been incredibly accurate. Since their orbit has them arriving roughly 4 minutes earlier each day, after several days it is pretty easy to sync up and see just when periods of especially good or especially poor coverage are.

I live on the west coast, Yuba City, CA to be exact. If someone on the east coast or midwest could keep track over even a 24 hour period and provide me with the info as to what sats were seen at what time etc we would have a better picture of what is actually happening and whether it is related to something like a preferred list or more of a time related issue.
 
SamsungVibrant said:
Okay lets test this orbit theory. I'm using an HTC spartphone and a Samsung Vibrant to see if the satellites in view and in use change as the satellites orbit around the globe.

Date 9/2/2010 Time 3:52 PM Los Angeles, California
HTC Phone: 11 sats in view, 8 in use
Sat numbers in use 2, 4, 9, 10, 12, 17, 27, 28

Vibrant:Same 11 sat numbers in view, zero in use

I'll update in a few hrs, lets see if the sats in use change as they orbit around the earth.
Click to expand...


Exactly what you should be seeing. 29 should be the first sat you get a lock on, for me that will be sometime around 5pm.

By 6pm you should see 3 locked on. 4, 29, 31..
 
krichek said:
Exactly what you should be seeing. 29 should be the first sat you get a lock on, for me that will be sometime around 5pm.

By 6pm you should see 3 locked on. 4, 29, 31..
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woops todays date is 9/1/2010, not 9/2...fixed that.

so you say by 6 pm I should see which sats exactly? how do you know where the satellites are, is there some real time map on the internet somewhere?
 
SamsungVibrant said:
also is your friend 10 miles away or 125? you said 125 in one post, the 10 in another, thats a big difference, may make a difference in your calculations.
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Sorry, My friend that is about 125 miles away (the Bay Area) has a captivate. I decided not to use him and just make it Vibrant only for now.

Big-Dog said:
I suspect that some satellites are never in view for certain parts of the world. Say the satellites that orbit the equator?

I believe that some satellites are only military as well, which could be why some are not used by civilian applications. So, with these restrictions and the fact that half of the satellites will be on the opposite side of the world at any particular moment, would leave only 10-15 satellites in view at any given time.
Click to expand...

None are military only. None orbit the equator either, here is a good site that describes their orbit. http://www.kowoma.de/en/gps/orbits.htm


SamsungVibrant said:
woops todays date is 9/1/2010, not 9/2...fixed that.

so you say by 6 pm I should see which sats exactly? how do you know where the satellites are, is there some real time map on the internet somewhere?
Click to expand...

By 6PM you should be locking on to 4, 29 and 31. The time may be slightly different for you since you are several hundred miles from me. This website will tell you what is in the sky above your location. LIVE REAL TIME SATELLITE AND SPACE SHUTTLE TRACKING AND PREDICTIONS
 
Based on the sats arriving 4 mins earlier each 24 hour period 29 just came into view in my position and is now locked on.. 29 and 31 will be the next to lock in. Both at roughly the same time.
 
Update is in bold

Okay lets test this orbit theory. I'm using an HTC spartphone and a Samsung Vibrant to see if the satellites in view and in use change as the satellites orbit around the globe.

Date 9/1/2010 Time 3:52 PM Los Angeles, California
HTC Phone: 11 sats in view, 8 in use
Sat numbers in use 2, 4, 9, 10, 12, 17, 27, 28

Vibrant:Same 11 sat numbers in view, zero in use

Quick update. 4:13 pm.. sat number 5 and 30 have now popped in view of the vibrant. Sat 30 has also popped in view of the HTC phone, but not sat 5.

Time is now 4:39, sat 28 has dropped from view, but I can't figure out which one took its spot, since there are still 11 in view. lol

Update 5:41pm Sat 17 has droped from view from both phones. After being on almost 2 hrs, finally the vibrant got 1 lock. The vibrant locked onto sat 29 after 2 hrs, but its touch and go, it locks on/locks off.

Update 6pm..sat 25 and 31 are now in view along with the other previous 9. (I lost track of which ones dropped, for these two to take their place...woops) The vibrant is no longer locked onto 29, now it is locked onto 31. Current in view: 2, 4, 5,9,10,12,25,27, 29, 30, 31.

Okay this is getting annoying lol

I'll update in a few hrs, lets see if the sats in use change as they orbit around the earth.
 
krichek said:
]

By 6PM you should be locking on to 4, 29 and 31. The time may be slightly different for you since you are several hundred miles from me. This website will tell you what is in the sky above your location. LIVE REAL TIME SATELLITE AND SPACE SHUTTLE TRACKING AND PREDICTIONS
Click to expand...

i cant figure that website out, can i just put my zip code and it shows which sats are in my view or what.

oh nevermind, it automatically detects your location via IP addy..but it only shows 1 sat in view, huh?
 
SamsungVibrant said:
i cant figure that website out, can i just put my zip code and it shows which sats are in my view or what.

oh nevermind, it automatically detects your location via IP addy..but it only shows 1 sat in view, huh?
Click to expand...

Doing something wrong lol.. When you get to the main page, Make sure "your location" in the middle of the page is right. If it isn't you can create an account and enter your exact location.

Then at the top under "In Your Sky" just click the link that says GPS.

Currently shows 11 in my sky.
 
SamsungVibrant said:
Update 5:41pm Sat 17 has droped from view from both phones. After being on almost 2 hrs, finally the vibrant got 1 lock. The vibrant locked onto sat 29 after 2 hrs, but its touch and go, it locks on/locks off.
Click to expand...


Odd, it's 6pm and as expected I now have 3 locked in 4, 29, 31. Hopefully some others can chime in here and post what they are seeing. It would help us to eliminate folks who have other problems as well as if it is affected greatly by time.

Here is a screenshot to show that I am in fact able to predict what will be locked in. :D


Edited to add: Sat 21 will be the next one to lock in at roughly 6:20 PM
 

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OMG UPDATE! I got 4 locked sats at 6:05 pm, look below in bold!

Update is in bold

Okay lets test this orbit theory. I'm using an HTC spartphone and a Samsung Vibrant to see if the satellites in view and in use change as the satellites orbit around the globe.

Date 9/1/2010 Time 3:52 PM Los Angeles, California
HTC Phone: 11 sats in view, 8 in use
Sat numbers in use 2, 4, 9, 10, 12, 17, 27, 28

Vibrant:Same 11 sat numbers in view, zero in use

Quick update. 4:13 pm.. sat number 5 and 30 have now popped in view of the vibrant. Sat 30 has also popped in view of the HTC phone, but not sat 5.

Time is now 4:39, sat 28 has dropped from view, but I can't figure out which one took its spot, since there are still 11 in view. lol

Update 5:41pm Sat 17 has droped from view from both phones. After being on almost 2 hrs, finally the vibrant got 1 lock. The vibrant locked onto sat 29 after 2 hrs, but its touch and go, it locks on/locks off.

Update 6pm..sat 25 and 31 are now in view along with the other previous 9. (I lost track of which ones dropped, for these two to take their place...woops) The vibrant is no longer locked onto 29, now it is locked onto 31. Current in view: 2, 4, 5,9,10,12,25,27, 29, 30, 31.

Okay this is getting annoying lol

Update 6:05pm...vibrant has 4 locked sats out of 12 in view! This Is Epic, Like Epic 4G.
vibrant in view 2,4,5,9,10,12,21,25,27,29,30,31 (red is in use). However, sat 21 and 31 have a SNR of zero.
The htc phone has droped 2 sats from view, but is locked onto 9 out of 9 sats. htc viewing and locked onto 2,4,5,9,10,12,29,30,31

:( short lived vibrant victory, its now 6:14pm and vibrant is now down to only 2 locked on sats. Sat 21 and 31, both with 0 SNR :(


I'll update in a few hrs, lets see if the sats in use change as they orbit around the earth.
 
I figured I would create a new post again just so folks couldn't accuse me of editing the old ones to show what I wanted them to show. ;)

As you can see, 4 Locked. The 4 I said, 4,21,29,31.

In about 15 mins.. 29 will still be in view but will no longer be locked on.. Leaving 4,21,31 as the sats that are locked.
 

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Okay, after doing all that work, I don't understand what this proved, other than my vibrant is back to zero locked on sats at 6:41, and the HTC phone is locked onto 9 out of 10 in view.

Basically I learned the vibrant can't lock onto all sats, but I knew that. Is there a bigger implication of this discovery?
 
SamsungVibrant said:
Okay, after doing all that work, I don't understand what this proved, other than my vibrant is back to zero locked on sats at 6:41, and the HTC phone is locked onto 9 out of 10 in view.

Basically I learned the vibrant can't lock onto all sats, but I knew that. Is there a bigger implication of this discovery?
Click to expand...


Heh, I said it was confusing. :D;)

Anyway a couple things that I think it proved to me anyway. Is that for one the Vibrant is a VERY sensitive GPS receiver. It was the only device I used that pretty much always saw every satelite that was currently available in my sky.

With how consistent it is both with the times in which it connects and with the satelites that it locks onto during those periods of time I think we have also eliminated hardware as the likely cause of the problem.

There is currently no way to trick the phone into having the correct time within the app that I know of (I have tried several different methods). If we were able to eliminate the time issue (since it is a known problem) then the results would probably be even more valuable, especially if they stayed the same...
 
So it is Sept 5th, still no knews about the GPS optimization. Anyone else think Samsung may just surprise everyone and release Froyo with the GPS optimization? Like a little I'm sorry surprise?

Also can someone go to troubleshooting section, I posted something about the screen constantly going to a lower brightness when the battery is low, like to know if yours overrides your settings and does the same.

thanks
 
SamsungVibrant said:
So it is Sept 5th, still no knews about the GPS optimization. Anyone else think Samsung may just surprise everyone and release Froyo with the GPS optimization? Like a little I'm sorry surprise?

Also can someone go to troubleshooting section, I posted something about the screen constantly going to a lower brightness when the battery is low, like to know if yours overrides your settings and does the same.

thanks
Click to expand...

At this point I've rather come to expect that the GPS optimization, fix, whatever, won't be released until the Galaxy version of Froyo is released. It does gall me that it hasn't been rectified to date; you'd think they'd take it more seriously given the importance of this particular phone.

As far as your screen issue goes, it's not something I've noticed. Then again I rarely let the battery go below about 30% before recharging.
 
For anyone that is interested there is a leaked ROM over on the xda forums that has pretty much fixed my GPS. I'm currently looking at gps test and it has 12 sats in view with 11 in use. The phone is incredibly quick to lock on now and even the time is finally displayed correctly.

Overall I've been using it for the better part of a day now and am really enjoying it. It seems even snappier and the media hub is now working as well, which I used today to show off to a couple relatives with iphones at my wife's birthday party. :D
 
krichek said:
For anyone that is interested there is a leaked ROM over on the xda forums that has pretty much fixed my GPS. I'm currently looking at gps test and it has 12 sats in view with 11 in use. The phone is incredibly quick to lock on now and even the time is finally displayed correctly.

Overall I've been using it for the better part of a day now and am really enjoying it. It seems even snappier and the media hub is now working as well, which I used today to show off to a couple relatives with iphones at my wife's birthday party. :D
Click to expand...

yes this was released by samsfirmware.com

but i want something official!

btw how is your accuracy on GPS test? how about in the real world?
 
SamsungVibrant said:
btw how is your accuracy on GPS test? how about in the real world?
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I've seen it get down to 7 feet, but it's usually somewhere between 11 and 15. I used it a couple times today with the factory nav in my car. Seems to be spot on, and this was out in the boonies where I get no cell service so it was all GPS it appears.
 
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