yashsingh1/xdaforums huggingface dataset:
[Captivate Android Development] Da_G:
I'll go first!

This is my test setup for the data in this post. You can see most of the output there on the screen. (I'll type it up for readability too) - There's about a 110 degree clear sky view, overcast. There is probably some minor multipath from the 2 story buildings nearby.

Phone setup is my own custom ROM (based on the recent Vibrant Froyo leak, with Cappy JH7 bits tacked on to address the various incompatibilities), JK3 baseband, Setiron 1.4.3 1200mhz kernel.

Format below is:

PRN of Satellite : Signal Strength : Used in Fix?

BT338 Standalone GPS (Tethered to laptop)

SV 5 : C/No 00

SV 6 : C/No 00

SV 15 : C/No 21 *

SV 16 : C/No 21 *

SV 18 : C/No 33 *

SV 21 : C/No 34 *

SV 22 : C/No 18 *

SV 25 : C/No 00

SV 26 : C/No 32 *

SV 29 : C/No 30 *

SV 30 : C/No 16 *

Captivate1 (Standalone internal GPS, to the left of BT GPS in photo)

SV 6 : C/No 13

SV 15 : C/No 23 *

SV 16 : C/No 19 *

SV 18 : C/No 32 *

SV 21 : C/No 12

SV 22 : C/No 19 *

SV 26 : C/No 21 *

SV 29 : C/No 33 *

SV 30 : C/No 11

Captivate2 (Standalone internal GPS, to the left of BT GPS in photo)

SV 6 : C/No 14

SV 15 : C/No 26 *

SV 16 : C/No 16 *

SV 18 : C/No 33 *

SV 21 : C/No 32 *

SV 22 : C/No 20 *

SV 26 : C/No 29 *

SV 29 : C/No 33 *

SV 30 : C/No 11

Some notes and observations:

I took 4 photos a few seconds apart from this angle to look at the signal fluctuations. You might notice Captivate1 SV 21 is an anomaly (12dB). The signal shows majorly degraded from the BT GPS and the Captivate2. Appx. 4 seconds before, the phone was getting 23dB on that satellite. The BT GPS and Captivate2 both remained at the same level (34dB, 32dB) - that might indicate some antenna issue after all, perhaps a marginal connection in some units. I'll do some more extensive comparison between these 2 units while I have them (2 or 3 days)

Here are 3 different MyTracks I took yesterday while driving: both GPS units on the dash.

AT&T Captivate Track:

http://maps.google.com/maps/ms?hl=e...26965825393652.000496745b69eeef7de5f&t=h&z=14

BT338 GPS Tethered to Captivate Track:

http://maps.google.com/maps/ms?hl=e...26965825393652.00049673fd50c60e8d690&t=h&z=14

Both Tracks overlaid (anyone know how to get one track as a different color for better visibility? I know you can in g earth..)

http://maps.google.com/maps/ms?hl=e...09,-117.346945&spn=0.053451,0.065746&t=h&z=14

[size=+2][Edit: Forgot to add, here is some data on fix times.][/size]

GPS in Standalone operation - Cold start

BT GPS - 59s

Cappy1 - 19s

Cappy2 - 16s

GPS in Standalone operation - Warm Start

BT GPS - 32s

Cappy1 - 12s

Cappy2 - 9s

GPS in AGPS operation - Hot Start

BT GPS (no AGPS, hot start only) - 3s

Cappy1 - 7s

Cappy2 - 5s

Interesting to note is that the 2 Captivates running the same software, used in the same position/enviornment, and trying to get a fix at the same time, Cappy2 consistently performs better than Cappy1. This again may point to some design-time issues with the GPS Antenna.
[Captivate Android Development] PersonOfKnownOrigin:
What software are you using to collect this data?
[Captivate Android Development] Da_G:
I'll post it in the first post, as i'm sure others will want to know too :) Look there shortly.
[Captivate Android Development] fatttire:
If we all post as replies to this thread that could get really cumbersome and hard to track.

Might I suggest another submission method?

Lol don't have time to do it but if you really wanted to get this done right you could code an algorithim that calculates average distance away from a street in my tracks... use that to generate a gps performance score... and use those gps performance scores to generate an average with standard deviations/ 95% confidence intervals.

That, would be so cool!
[Captivate Android Development] Da_G:
It would be great if there was so much data to be had that it was hard to track. Right now the situation is exactly opposite of that :) Bring it on! We can worry about managing the flood of data later, when there is a flood of data. :)

The problem with calculating an average distance like that is that it won't factor in enviornmental factors. The GPS might perform great with a 110 degree sky view and minimal multipath, with a 110 degree sky view and a mountain nearby, it might go bonkers. Due to the frequency range and transmission type, GPS signals are very prone to enviornmental factors. (These same weaknesses are also their strength in being so accurate in the right enviornment)

Updated first post with info about the apps I used.
[Captivate Android Development] TXRangerXDA:
This may count as anecdotal, but...

You asked for My Tracks data... something I have noticed is that, for me at least, My Tracks wil be pretty damb accurate if running in the background, while navigation or maps can't track well I the foreground at all. In fact, even My Tracks won't do well in the foreground. Not sure what this means, but liking forward to any developments on this front.
[Captivate Android Development] shep211:
Dam Da_G great to see you. Long time since I have worked with wm but always enjoyed making roms from your leaked builds. I will work on collecting gps data. I do onsite IT work so I will log gps all day and post back when I get a few days of data.
[Captivate Android Development] Da_G:
Good to see you too shep :) Re: WM, The King is dead! Long live the King :)

Updated post 2 with some more interesting data regarding lock times. Re: My Tracks and performance in foreground/background, i'll slate that test for tomorrow. I think you're wondering if the CPU usage may have something to do with accuracy? It's certainly possible but if most of the calculations are handled in the baseband like I think, not likely. Either way, tomorrow's test will answer that :)
[Captivate Android Development] drancid:
i'm not sure if this is the data you want but i matched all lbstestmode settings as yours, and did 3 position tests, took screen shots right after sat locked.

hope this useful... :p

here's my cappy's setup.

Rom : Perception Build 5

Kernel : SetiroN's v1.4.3 1350 Mhz OC'd

and here's the results

First Test

SV 22 : C/No 35 *

SV 06 : C/No 35 *

SV 03 : C/No 35 *

SV 09 : C/No 33 *

SV 19 : C/No 32 *

SV 14 : C/No 29 *

SV 21 : C/No 28

SV 27 : C/No 13

Second Test

SV 06 : C/No 37 *

SV 03 : C/No 36 *

SV 22 : C/No 35 *

SV 14 : C/No 33 *

SV 19 : C/No 32 *

SV 21 : C/No 30

SV 09 : C/No 28

SV 18 : C/No 11

Third Test

SV 03 : C/No 34 *

SV 22 : C/No 32 *

SV 06 : C/No 32 *

SV 19 : C/No 31 *

SV 09 : C/No 30

SV 14 : C/No 28 *

SV 21 : C/No 23

SV 18 : C/No 13

Screen Shots

View attachment 455707 View attachment 455708 View attachment 455709
[Captivate Android Development] born_fisherman:
Perception Build 6 w/ JM9 gps files

Indoors - Currently clear skies

SV 18 : C/No 33 *

SV 12 : C/No 32 *

SV 22 : C/No 31 *

SV 25 : C/No 30 *

SV 09 : C/No 30 *

SV 14 : C/No 26 *

SV 21 : C/No 23 *

SV 27 : C/No 22 *

SV 15 : C/No 20 *

SV 31 : C/No 18 *

View attachment 455721
[Captivate Android Development] drancid:
can't enlarge the image... :(
[Captivate Android Development] Da_G:
Great post, drancid. What was the enviornment like at the time? How far apart were the fix attempts? All on the same device?

I'm guessing it was indoors or with a partially blocked view of the sky?

@born_fisherman:

Looks like it was just a thumbnail that uploaded. No link to a larger photo, and the text is too small to read :(
[Captivate Android Development] drancid:
thx. :D

yes, results from my cappy. just have one device.

about 2 minutes interval.

tested in my back yard. big tree and two story houses were near me but cappy was facing clear sky.
[Captivate Android Development] born_fisherman:
updated my post - The JM9 files work wonders. Oh, I also have SUPL Secure Socket ON
[Captivate Android Development] majinzen:
Ok, I'm indoors. Waited 5 minutes between tests. One device.

ROM - di11igaf's UGJK3, MODEM - JK3, KERNEL - SetiroN 1280 1.4.3

Gps Fixes - Jupiter V006 + JM9 Files

TEST 1

PRN: 25 CNo: 35

PRN: 31 CNo: 34

PRN: 22 CNo: 34

PRN: 18 CNo: 29

PRN: 14 CNo: 20

PRN: 30 CNo: 19

TEST 2

PRN: 25 CNo: 32

PRN: 22 CNo: 31

PRN: 31 CNo: 28

PRN: 30 CNo: 28

PRN: 24 CNo: 23

PRN: 18 CNo: 22

PRN: 14 CNo: 18
[Captivate Android Development] born_fisherman:
Since you are using the JM9 files, use Supl.google.com / 7276 to get better results
[Captivate Android Development] majinzen:
I've tried both and I get better or equal results with this config. Sometimes supl.google.com takes forever to lock on for me.
[Captivate Android Development] born_fisherman:
See, that is really what I would like to find out more about the GPS - why it's different for others and why it isn't consistent!
[Captivate Android Development] patrickdo:
Assonance 2.0 (stock = supl.google.com 7276, secure socket off, standalone, hot start, http://xdaforums.com/showthread.php?t=856877)

#1007

sitting near a window with a clear view of the sky

TTFF 15s

Accuracy: 25.0 m

PRN 31 = 28*

PRN 23 = 22*

PRN 32 = 21*

PRN 24 = 21*

PRN 20 = 21*

PRN 11 = 21*

PRN 14 = 18*

PRN 30 = 17*

5 min later:

TTFF 15s

Accuracy 15.0 m

PRN 32 = 30*

PRN 20 = 29*

PRN 31 = 25*

PRN 24 = 25*

PRN 11 = 24*

PRN 30 = 20*

PRN 23 = 14

PRN 14 = 13

FWIW, this setup tracks very well on some car trips, less well on others.

What clues can you get from seeing our signal strengths, besides that it's erratic..?
[Captivate Android Development] drancid:
We all know google server is much better but...

Da_G said match the lbstestmode settings same as his...;)

NOM..:D
[Captivate Android Development] Da_G:
@patrickdo:

Some have suggested that the GPS Antenna on the Captivate may be substandard. Getting a good sample of raw signal strength from a number of users is the best way to see if that is indeed the case. (So far, it looks as though there may be a problem with some units, as there are marked differences)

@Everyone:

Regarding the settings on SUPL/CP tab, these don't matter as long as you have operation mode set to Standalone. It won't attempt an AGPS connection at all in this case so SSL on or off has no bearing. Do note a SUPL server cannot be running both SSL on and off. You might check the adb logcat output - one of those is probably making a sucessful AGPS connection while the other one is not (connection refused) - so you are having better performance either with AGPS working or without AGPS.

Track from Captivate with My Tracks in foreground

The GPS won't function after a short time on cappy with GPS Logging up, and LbsTestMode is entirely blank.

Here's a photo of the GPS "stuck on" after GPS Logging - no apps running that could be using the GPS. GPS remains completely nonfunctional until a reboot.

[edit: nevermind about GPS + Mobile AP. Turns out GPS Logging was the cause. Does GPS Logging cause this for anyone else? (in lbstestmode)]
[Captivate Android Development] bmunday:
can everybody post the model # of phone as well?: 1007, 1008, 1009 , 1010....?
[Captivate Android Development] tegots:
http://maps.google.com/maps/ms?hl=e...d=116589207429410746424.000450e46dbf4fc3d7ef0
[Captivate Android Development] born_fisherman:
My results from "Factory fresh" Odin JF6 Flash - No tweaks made to LBS settings. My Captivate is a 1006 model

Test 1 (in kitchen (15ft from window, clear skies)

PRN: 20 CNo: 32 *

PRN: 24 CNo: 30

PRN: 11 CNo: 29 *

PRN: 19 CNo: 27 *

PRN: 17 CNo: 27 *

PRN: 28 CNo: 25

PRN: 07 CNo: 25 *

PRN: 08 CNo: 21

Test 2 (next to window, indoors, clear skies)

PRN: 20 CNo: 41 *

PRN: 28 CNo: 36 *

PRN: 24 CNo: 33 *

PRN: 11 CNo: 31 *

PRN: 17 CNo: 30

PRN: 19 CNo: 28 *

PRN: 07 CNo: 26 *

PRN: 13 CNo: 23 *

PRN: 08 CNo: 23 *
[Captivate Android Development] phlunkie:
For this testing I am willing to run on a pure stock setup. Should we all do that? This way we do not start more flame wars of my rom is bettet than yours.

I also have an external gps unit that I started using on the captivaye out of shear frustration. I can try using it in the tests also. What would the ideal test setup be? Captivate vs laptop? Cap with internal/cap with external/then pc and gps combo?

Live north of orlando, structures are mostly trees. I have time today to run tests. And the skies are very clear. Input is greatly welcome.
[Captivate Android Development] mr.valacky:
this is mine:

outdoor test:

How to access LBSTESTMODE in Xperia X10? (i heave x10 & x8)

[ROM][FROYO]▽▲ AXURA Captivate Edition ▼△[RC1]
[Captivate Android Development] CLShortFuse:
Da_G,

I returned my Captivate but take a look at my GPS thread here about the Jupiter files. It doesn't have much, but it's something.

As for getting the source code you mentioned in the other thread (I'm guessing this thread will be your base), Samsung is obligated to give anyone the source code as long as it is requested. It is a required license term stated by Google when licensing AndroidOS.

I, myself, have pretty much lost hope aftering seeing Samsung release a i9020t to FCC, which is the same i9000 we use but a new GPS antenna...
[Captivate Android Development] bleeman:
Here is my data, running ROM in my sig and using JM9 fix. Dark, cloudy day.
[Captivate Android Development] Da_G:
Thanks for the posts so far guys, great info :)

@CLShortFuse

I did indeed read through your thread in its entirety, lots of good data there too. Reading all of the posts there is partly what made me ask for the signal strength info from everyone. The GPS seems to be able to perform spot-on at times, and quite off at other times. If it is indeed an antenna problem, the NMEA data should show a drop in signal that corresponds to the loss of tracking.

So far everyones signals seem fairly consistent, not low enough to account for the kind of troubles it has in tracking. (i.e. the confidence drops, so the location is off by a corresponding amount, but the track should not drift off in some odd direction for a period of time)

It may be that the i9020t antenna pulls in more signal to compensate for the problem, but I doubt it's the root cause at this point. I did request radio source from sammy last week, so far their reply has been only to ask me to define the acronym "ETA".. lol :)

@phlunkie

See if you can grab lbstestmode satellite signal strength output indoors, then do the same thing from the bluetooth GPS using the bluetooth gps app. Grab snapshots from both indoors and outdoors. It will be useful to gauge the antenna quality of the Cappy vs. the BT GPS. Also, what model is it?

@tegots

Looking closely at your track, looks like you are consistently losing fix in areas with high multipath (GPS Signal reflections from tall objects) - this is interesting and again points to an algorithm deficiency with the GPS. In a multipath situation the GPS chip has to decide which signal comes directly from the satellite, and which signal(s) are a reflection. It should put more weight towards the signal it determines is the original, and there should be a little drift in the path away from the direction of the multipath. (i.e. if you are passing a series of tall buildings on the left, the signal should drift a bit to the right) - however it seems to be consistently losing a fix in this situation rather than drifting. [edit: the specific area i'm referring to is here]

@Everyone

Can anyone else put up some My Tracks in an area with high multipath (tall objects)?
[Captivate Android Development] cgm8:
Here is mine.

ROM Preception Build 5 +jupiter v006 + gpsjm9 fixes

LbsTestMode setting

Operation Mode: Standalone

Start Mode: Cold Start

deleted gps data each test

Location: Backyard

Weather: Heavy Cloud

Test duration: 2 minutes

Test1

Test2 Back metal cover off ( I found this with better signal and tracking)
[Captivate Android Development] aleadam:
I have observed that variability in my phone. It does not seem to be just a problem of signal, since I got a couple of days ago a much better tracking on a rainy day with my phone in the cup holder than tonight with a semi clear sky and the phone right below the car windshield. I had a very low battery tonight but that's just anecdotal and as such should be banned from this thread :)

Usually gps test or lbstestmode give me signal results ranging from high 20s to low 40s, with an average of around 30-32 (using both CLShortFuse's jupiter 6 files and gpsjm9 fix). Kind of what everyone else's getting.

I'll hopefully post next week data from downtown Boston. If you find (or write) and app to grab raw nmea data I'll be happy to run it.
[Captivate Android Development] Krynn!:
Try this for collecting nmea data:

http://www.appbrain.com/app/aspara/com.blossoom.aspara

It seems to work in the, oh, 5 seconds or so that I've run it so far. I'll give it a real test when I get up tomorr... er, today.
[Captivate Android Development] dfellars77:
Will this help? Delete if not :)

We have 2 Captivates (10.06 and 10.07,) running identical roms as well as a very accurate GPS in our car. In addition to the LBStestMode data, I may be able to provide a video of both caps navigating alongside my car's GPS. My normal route takes me from low rises, to the clear sky of LSD, to downtown. Would this be of any assistance?
[Captivate Android Development] Da_G:
@dfellars77

Yes, that would be very helpful :)

@Krynn!

Yeah, I mentioned that program a few posts back. It does output NMEA data to the screen and allow saving to SD, but the program's coded a little odd and after the buffer gets larger (like during the course of a 10 minute drive) the program becomes non-responsive, and you can't save the data.

I'll see if I can whip a program up for this purpose as I don't see any other (free) one that can do it.
[Captivate Android Development] warri:
Good to see you Da_g... now that your on the case well get this god crappy fixed.. will get some data for you.
[Captivate Android Development] nephets0:
here is a mytracks i took earlier when walking my dog.

http://maps.google.com/maps/ms?hl=en&ie=UTF8&msa=0&msid=106036230981101276067.000496b2065f4b31f826e&ll=36.176163,-95.871506&spn=0.010739,0.022724&z=16

running cognition2.3b3 and jupiter v006 and the clockwork mod file posted here from the 'how i fixed my gps' thread.
[Captivate Android Development] CLShortFuse:
Da_G, i don't have android anymore but I have developed for it. If you do:

adb logcat

you can get, IIRC, the NMEA output.
[Captivate Android Development] nephets0:
forgot to add that the random line through someones house was when i bent over to check on my dog. the phone was also in the outside pocket of my carhartt coat if that matters any.
[Captivate Android Development] madmack:
wow, what settings do you use in lbstestmode ? supl/operation mode/..
[Captivate Android Development] nephets0:
supl is google. operation mode is standalone. i'm trying different rom today so i cant check cognition.
[Captivate Android Development] Da_G:
@CLShortFuse

I wish it did! There is some GPS related output there but not NMEA. I'm already working on an app to capture it with some on screen display output :)
[Captivate Android Development] MikeyMike01:
ROM: Assonance 3.1

GPS Settings: Use Wireless Networks, Use GPS satellites, Use sensor aiding

LBSTestMode Settings:

SSL=1
SSL_TYPE=0
POSITION_MODE=7
OPERATION_TEST_MODE=0
ACCURACY=50
SESSION_TYPE=1
SERVER_MODE=1
ENABLE_NMEA=false
START_MODE=WARM
GPS_LOGGING=0
AGPS_MODE=0
DYNAMIC_ACCURACY=1
ADDRESS_MODE=1
OPERATION_MODE=MS BASED
TIME_BTW_FIX=0
USE_DEFAULT=true
DYNAMIC_ACCURACY_VALUE=50
SUPL_PORT=7276
ENABLE_XTRA=true
SUPL_HOST=supl.google.com
NUM_OF_FIX=0
TIMEOUT=1000

Application Used: My Tracks 1.0.21

Location Of Phone: Passenger Seat

Results: http://maps.google.com/maps/ms?msa=0&msid=206120002681569822611.000496c4d2f5c53293bff
[Captivate Android Development] ewingr:
Here is a MyTracks Map.

FYI: Perception Build3.

Something I find interesting: Recently I changed the Google Nav app to Satellite. I find that the route it has mapped for me to drive is off the road by a few feet, almost exactly what I seen when I later look at a My Tracks. I find that interesting, and wonder if there is any correlation. So many discuss the MyTracks showing them 'off the road'. The point is, that the route to drive shouldn't be calculated to drive 'off the road', and it clearly is. Another interesting thing, with the Map in Sat view on MyTracks you will notice toward the end of the drive, teh tracks show me driving the 'old road', as was in the map (not current), as opposed to what I actually drove, which was around the loop. It will be very obvious. (I don't have much faith in MyTracks based on this stuff).

I didn't catch my specific SNRs on this route. I did post a test with noting the SNR range I was getting based on different tests: 1.) With stock Perception Build 3 2.) With Jupiter 6 on it 3.) With the JM9GPS files loaded. I got best SNRs with just putting Jupiter 6 on.
[Captivate Android Development] nephets0:
i will try to do a mytracks on the way to work today see what it does.
[Captivate Android Development] MikeyMike01:
Bump for more data.
[Captivate Android Development] Cezar`:
non-relevant. deleted
[Captivate Android Development] Da_G:
Still working on the program to capture raw NMEA. Got the UI pretty much done, working on the guts of it now. My first Java/Android app, so i'm learning a new programming language and a new API at the same time! Fun times. I find myself wondering why I didn't write it in native code rather than Java, oh well, gotta learn sometime :)

From what i've got done so far I don't see any indication that the MyTracks output would differ at all from the NMEA output (i.e. it would be the same reported location) - but once i'm done it should be easy enough to overlay a track rendered from the NMEA data on top of a MyTracks track to see how accurate it is.
[Captivate Android Development] CLShortFuse:
Da_G, I got a Captivate again. I drove the same route again with the new Captivate

Old: http://maps.google.com/maps/ms?ie=UTF8&hl=en&msa=0&msid=108472444080796738089.000491a2c10ac25693114

New: http://maps.google.com/maps/ms?hl=e...d=108472444080796738089.000497031609460104f56

I think the issue is hardware related. I have a 1010 phone (manufactured Oct 2010) while I got the other one in September I think (so it was probably a 1008 phone). This might have a better manufactured-to-spec antenna.

The phone does have a connector for an external antenna in the back, above the battery. If you believe it's software, then using an external antenna should have the same problems. I don't have adapters for that connector but you might want to try with that.

btw, I can develop for Android and have done a GPS tracking app. Let me know if you need tips.
[Captivate Android Development] born_fisherman:
I just wish samsung would admit that it was software or hardware...It has been almost 5 months now since release date.

@clshortfuse - is your track from stock firmware?
[Captivate Android Development] madmack:
I just wanted to let you guys know that hardcore over at the i9000 forums have tweaked some kernel schedulers and that fixed many GPS units including mine. It seems my problem previously was that the signal is strong and good when am stationary. As soon as I start moving, the signal drops and I lose many satellite locks.

anyways, I enabled his kernel scheduler tweaks and these problems are gone completely. I was able to track and navigate using google nav in both DC and Boston (urban canyons) without a problem. It is also worth noting that initial locks have improved significantly as well.

Maybe the GPS module/driver was not given enough CPU cycles ? I'm not really sure what he did, but it definitely fixed it here.

I apologize if this is not the right place to post this, but I was thinking maybe you guys are looking in the wrong place atm.
[Captivate Android Development] CLShortFuse:
yes, it was stock. i'm running cognition's latest now to test.
[Captivate Android Development] fatttire:
It's the right place if that leads one of us to try it and post our results. I just want to clarify. On Setiron's kernel there are kernel scheduler tweaks - are these the same as hardcores? how did you add the tweaks?

Edit: setiron's latest kernel has it