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All things GPS
- Thread starter enjoimark
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- samsung captivate
Rred
Member
Buddha, if you think 48 feet (14.6 meters) is not accurate, I would urge you to look at:
www.fs.fed.us/database/gps/gps_standards/gps_data_std_kc.ppt
particularly the chart on page 16, where accuracy is compared from a number of recreational GPS units under different conditions.
Ten meter accuracy is quite good for a moving "civilian" GPS that is not sitting still and averaging readings. To get any better, i.e. 3-meter, you need a differential GPS ($$) or a WAAS-enabled GPS.
For the last five years almost all consumer GPSes have been WAAS-enabled, but to my knowledge there are NO CELL PHONES using WAAS augmentation, because it adds to the bulk,the cost, the CPU overhead, and the power consumption.
WAAS uses additional ground-based stations to actually measure atmospheric interference and send a correction signal on top of the other GPS satellite signals, and atmospheric interference ALL BY ITSELF can produce more than a 10-meter error in GPS readings. When a storm front is anywhere nearby, that's especially relevant.
48 feet? A little loose, but not unusual for a non-WAAS civilian GPS that isn't doing position averaging. (And it is possible that the software in the cell phones isn't doing position averaging at all. Who knows?)
I'm typically within 3 meters at all use cases, except indoors - then it climbs to about 10.
Very common Evo result, with many on that forum posting better than 2 meter location.
Very common Evo result, with many on that forum posting better than 2 meter location.
Rred
Member
Dunno if they snuck in WAAS without "bothering" the customers about it, or perhaps they've written some slick software that's making good use of the assist modes and doing more intensive calculations?
There are also different ways to calculate position from the satellite information. In theory, one way that AGPS can perform better is by sending the raw satellite information (from the GPS) out to the network, where the actual processing and calculation is done by better equipment. And if THAT equipment is also set up to monitor WAAS corrections for your area, it can apply them before sending the position back to the phone.
All the more reason that folks who compare GPS, without disabling all the assist functions, aren't really comparing the GPS itself. Most of us look at the box in our hand and conveniently forget there's a billion dollars worth of hardware feeding that display.<G>
There are also different ways to calculate position from the satellite information. In theory, one way that AGPS can perform better is by sending the raw satellite information (from the GPS) out to the network, where the actual processing and calculation is done by better equipment. And if THAT equipment is also set up to monitor WAAS corrections for your area, it can apply them before sending the position back to the phone.
All the more reason that folks who compare GPS, without disabling all the assist functions, aren't really comparing the GPS itself. Most of us look at the box in our hand and conveniently forget there's a billion dollars worth of hardware feeding that display.<G>
I've helped launch some of it. 
s.m.knipe
Android Expert
The Evo numbers arr not exaggerated, my n1 my g1 and my sister's aria consistently get 1-2 meter readings and hold that throughout the session. Indoors, where gps' are NOT SUPPOSED to work they get about 5- 6 meter reading, downstairs in a 1930's well-built cape cod...
Evo's little secret is that while its processor lacks the GPU power found in your phones, it's CPU is possibly still the best out there - double the width of your data paths internally and able to far surpass basically anything else in that one regard. Couple that with the fact that its radio+gps chip is designed by the exact same manufacturer - the whole package was designed integrally rather than integrated from other parts. Following Qualcomm's implementation guidelines, HTC'd better have good performance. (What little I know says, more complex algorithms, not more phoning home via the cell towers.)
That said - I'm just not convinced yet that similar isn't possible with the Galaxy-S class.
That said - I'm just not convinced yet that similar isn't possible with the Galaxy-S class.
ghost03
Newbie
I went through all the reasonable channels to get this problem fixed. (I had to laugh because AT&T told there was no GPS in the Captivate at one point).
I tried a different route and filed a formal complaint against AT&T and Samsung with the Better Business Bureau. They accepted my case today and gave AT&T 30 days to answer. I'm not sure what happens after that but I figure if enough of us complain through legitimate channels, maybe some will take notice. It takes about 10 mins to file the complaint depending on how fast you type.
Here is the link:
United States and Canada BBB Consumer and Business Reviews, Reports, Ratings, Complaints and Accredited Business Listings
I tried a different route and filed a formal complaint against AT&T and Samsung with the Better Business Bureau. They accepted my case today and gave AT&T 30 days to answer. I'm not sure what happens after that but I figure if enough of us complain through legitimate channels, maybe some will take notice. It takes about 10 mins to file the complaint depending on how fast you type.
Here is the link:
United States and Canada BBB Consumer and Business Reviews, Reports, Ratings, Complaints and Accredited Business Listings
sremick
Android Expert
Well, they've taken "GPS" off as a list of features if you look the phone up on AT&T's website. Best Buy has done the same thing.
Be sure to let us know how it turns out. Unfortunately the BBB doesn't really have any teeth but who knows.
skinien
Android Enthusiast
Awesome dude, I just filed a complaint.
ghost03
Newbie
sremick
Android Expert
That's a very interesting thought. The iP4 could be fixed with a cheap-o bumper - and look at the stir that was.
If such a thing exists, it would be strictly a design patent - not what you're thinking.
Hitting with a patent troll is much less effective than threatening to hit them with another antenna-kinda thing in the mainstream market.
Hitting with a patent troll is much less effective than threatening to hit them with another antenna-kinda thing in the mainstream market.
Samsung doesn't have a "galaxy s" patent. They (along with all tech companies) patent the components that are patentable, but rarely the whole device. Plus, what would you be able to do with it? All a patent does is give the holder the right to control use. You can't sure them on their own patent.
Still a patent claim does not equate to a contractual promise for service or capabilities. 
gcobb
Android Enthusiast
I think it's safe to say they're stepping up to the plate with an OS upgrade. I'm patiently waiting.
After updating to the official 2.2 via kies 1.53 the issues I had with the gps are gone now. Took the exact same route as yesterday and today was bang on no issues at all. The 2 issues I had on 2.1 were errors to find my locations as well the wait time for it, now its quick. Second was inaccuracy especially making a turn, now flawless... So far lol
I don't know if Samsung has done something to the newest builds of Captivates or not but since my older Captivate was replaced by ATT two weeks ago with a brand new unit I have had no GPS issues despite using it under the same situations. I have used four Captivates now with three known build dates (Aug10, Oct10, unknown because it only worked for three hours, and Dec10)
My first Captivate had major GPS issues but I'll discount that phone simply because I fell prey to Flash-Fever and installed 2.2 beta so regardless of lousy GPS performance I altered the phone significantly which, I believe, tends to invalidate any observations. Phone #2 and #4 were intentionally kept fairly stock with only some Market Apps installed common to both phones (Skymaps, Google Maps 5, Watchdog Lite, etc) and when I did install apps they were several days apart in most cases so I would have noticed a severe change in GPS if it seemed to be program related. I habitually run the GPS over the same two routes to work and home five days a week so I think I have a good baseline as to how any local interference might affect signal quality and/or accuracy. Also, both phones below used the exact same Body Glove case, in the same Bracketron phone holder mounted in the same place in the same car. What I have noticed:
Phone #2: Would have me off the freeway anywhere from 4-7 places, mainly where multiple freeways overlapped each other regardless of whether I was transitioning from one to another or not, and towards the end I was losing GPS lock at least once per trip. GPS time to first lock in my car was normally fairly rapid, under 30 seconds in most cases but forget trying to get a lock if the car was already in motion when GPS started up. My car was almost always surrounded by a large blue circle while using Google Nav, large enough that it covered the entire freeway and usually at least the first frontage road if not more. Intentionally forcing the phone to reroute took up to 15 seconds at residential street speeds and the phone frequently overshot intersections where I was stopped at a sign or light. My stationary signal strength was normally in the upper 20's to the low 30's and fluctuated fairly often. Using GPS Test for positional accuracy while standing in my back yard would fluctuate between 32 and 49m and similarly touching the blue dot in Google maps would give me, at best, 20m.
Phone #4: Has only had me off my actual track one time, for less than 5 seconds, and that was when I started up the GPS while doing 70. It tracks overlapping freeways perfectly and isn't confused as to which I'm on. Lost GPS lock has not occurred. Time to first lock is comparable between the phones except this one, as noted, can lock while I'm moving. My blue arrow icon is usually sharply defined but at night I notice some 'fuzz' around it, not sure if that's actually circle or an attempt to indicate 'headlights' like another GPS unit I owned used to do. Rerouting is about twice as fast and when I stop, the arrow stops. Stationary signal strength is high 30's on most birds with one or two above 40, peaking at 46 observed max and fluctuation seems to be far less though I have no solid data to quantify that observation. Positional accuracy starts at 32.8 and drops to 16.4 via GPS test but the other day I noticed Google Maps had me at 5m in the car while sitting at a drive thru.
Use wireless networks is unchecked checked on #4 (out of the box setting) but I repeatedly tried both settings on phone #2 and failed to notice any difference. I haven't used the LBStest feature on either phone #2 or #4 so they should both be set to whatever Samsung default is. I did use GPSRestore on #2 but nothing changed, probably because I hadn't changed anything with LBSTest.
In summary, phone #4 works as well as I have come to expect from a cell phone GPS. So far I am confident in its ability to get me from point A to B with a minimum of fuss although, after three bad phones, I admit to a lingering doubt wondering when/if the other shoe will drop.
My first Captivate had major GPS issues but I'll discount that phone simply because I fell prey to Flash-Fever and installed 2.2 beta so regardless of lousy GPS performance I altered the phone significantly which, I believe, tends to invalidate any observations. Phone #2 and #4 were intentionally kept fairly stock with only some Market Apps installed common to both phones (Skymaps, Google Maps 5, Watchdog Lite, etc) and when I did install apps they were several days apart in most cases so I would have noticed a severe change in GPS if it seemed to be program related. I habitually run the GPS over the same two routes to work and home five days a week so I think I have a good baseline as to how any local interference might affect signal quality and/or accuracy. Also, both phones below used the exact same Body Glove case, in the same Bracketron phone holder mounted in the same place in the same car. What I have noticed:
Phone #2: Would have me off the freeway anywhere from 4-7 places, mainly where multiple freeways overlapped each other regardless of whether I was transitioning from one to another or not, and towards the end I was losing GPS lock at least once per trip. GPS time to first lock in my car was normally fairly rapid, under 30 seconds in most cases but forget trying to get a lock if the car was already in motion when GPS started up. My car was almost always surrounded by a large blue circle while using Google Nav, large enough that it covered the entire freeway and usually at least the first frontage road if not more. Intentionally forcing the phone to reroute took up to 15 seconds at residential street speeds and the phone frequently overshot intersections where I was stopped at a sign or light. My stationary signal strength was normally in the upper 20's to the low 30's and fluctuated fairly often. Using GPS Test for positional accuracy while standing in my back yard would fluctuate between 32 and 49m and similarly touching the blue dot in Google maps would give me, at best, 20m.
Phone #4: Has only had me off my actual track one time, for less than 5 seconds, and that was when I started up the GPS while doing 70. It tracks overlapping freeways perfectly and isn't confused as to which I'm on. Lost GPS lock has not occurred. Time to first lock is comparable between the phones except this one, as noted, can lock while I'm moving. My blue arrow icon is usually sharply defined but at night I notice some 'fuzz' around it, not sure if that's actually circle or an attempt to indicate 'headlights' like another GPS unit I owned used to do. Rerouting is about twice as fast and when I stop, the arrow stops. Stationary signal strength is high 30's on most birds with one or two above 40, peaking at 46 observed max and fluctuation seems to be far less though I have no solid data to quantify that observation. Positional accuracy starts at 32.8 and drops to 16.4 via GPS test but the other day I noticed Google Maps had me at 5m in the car while sitting at a drive thru.
Use wireless networks is unchecked checked on #4 (out of the box setting) but I repeatedly tried both settings on phone #2 and failed to notice any difference. I haven't used the LBStest feature on either phone #2 or #4 so they should both be set to whatever Samsung default is. I did use GPSRestore on #2 but nothing changed, probably because I hadn't changed anything with LBSTest.
In summary, phone #4 works as well as I have come to expect from a cell phone GPS. So far I am confident in its ability to get me from point A to B with a minimum of fuss although, after three bad phones, I admit to a lingering doubt wondering when/if the other shoe will drop.