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Some people might experience with certain GPS software.
If you look at the log of the NMEA log, you might realize that it burst out every 6-10 seconds. After that you might wait for another 6-10 sec, which is unusable for real-time navigation. If you happen to meet this trouble.
I have a way which could allow normal update intervals.
Install GPSGATE, it create virtual GPS COM PORT and re-route the NMEA data.
Install GPSGATE, just use the default settings, it create the virtual GPS port as COM 1.
Just use GPS software on COM 1 .
software url: http://franson.com/gpsgate/
Can anyone confirm this works? Ive noticed my GPS works the same way. Im using the Kaiser / TyTn II with Mapking and i notice that i also get my signbal ins bursts and NOT a smooth stream. Anyone know if this will resolve the problem?
What is the update intervals with GPSGATE ?
Do you mean GPSGATE must be run concurrently with the other software TomTom 6 for example ?
It would be a good workaround for people who encounter this GPS issue.
could this be some delicious spam?
How exactly does the OP propose that a user space application can make the hardware produce data in a smoother stream?
I call BS.
seems like BS to me too...Probably some spam Can anyone who has tried it out verify if it really works or not?..
THKS
You don't need to use other GPS software concurrently,
just use the GPSGATE and mapking will do.
Remember you have to modify the settings in mapking to use the virtual com port ( com1 default)
Not SPAM
I am not sure, this is BS.
If I am not mistaken the GPSGATE will act like a "router" (middle man) between the GPS hardware (Internal GPS of Kaiser) and the application (TomTom).
If the GPS hardware is faulty (having problem) with bursting data every 10 seconds, then the GPSGATE will also receive bursting data every 10 seconds.
So, that's useless as long as the problem is in the GPS hardware.
Gpsproxy should be able to do the same thing and its free.
GPSGate is a splitter, allowing using more than one application with the same NMEA stream. It creates another virtual GPS COM port, that's it.
GPS on the Kaiser works great and I'm on SatNav business. Aquisition time is fast, reception is great and update ratio is every 1 sec, just like any other civilian GPS receiver. GPS is NOT evaluated by the refresh rate you see on the screen, other software will give you other rate, try OZI Explorer for instance. I used Kaiser with TomTom, Destinator & Ozi, all works really great even comparing to Sirf III GPS chipset embedded devices such as Eten X500, HTC Artemis and Asus 535.
Last, Microsoft has included the same functionality of GPS Gate in WM5 and WM6 under settings. You do not need to install any additional SW, you can send "trueman 12345" (the guy who opened this thread with 2 posts history) your money directly.
Thanks RonenB for this very usefull precision !
Thanks as well RonenB, However, it does not solve the odd occasional pause in the data that we're seeing. Is this hardware or software that needs help in the Kaiser?
Actually I'm not so sure we have defined the problem accurately here.
Examining the signal from the GPS shows some interesting info.
1
A satellite is locked onto for perhaps only one or two seconds at a time.
2
Several satellites can achieve a lock but out of these a few will be lost every few seconds
3
New satellites are also acquired every few seconds.
The Result
If you are in the presence of many satellites then there is a constant dropping of some and locking onto others. This leads to no problems as there are always a few satellites locked on and data flow is smooth.
BUT
If you are in the presence of only say 2 or 3 satellites it is possible to drop these two or three (as indicated above), but no new ones are acquired. In this situation there will be a few seconds before the first 2 or 3 lock in again. Result a gap in data flow to your GPS software.
Meaning
The Internal GPS is not polling data in bursts. In other words you cannot turn up the frequency of data polling (possible baud rate adjustment maybe). The data is continuous but if there are too few satellites then there can be gaps where it drops some satellites and does not lock others.
There are various applications that can show this behaviour graphically but tomtom shows it well on the satellite view screen.
Compared to external GPS satellite locks this works in a strangely different way. You will see the bars jumping around from a lock on this one to that one continuously. Only a problem as I say when there are only a few satellites in sight.
Mike
PS - I cannot see the advantage of GPSGate in this particular situation as it is due to momentary periods when no satellite is detected.
Having said all of the above, I find the GPS perfectly adequate for general use. Perhaps if I need spot on plotting data then it might be weak. However if I need that unusual level of accuracy I would not use my phone to do it. I regularly use mine in place of my car's tomtom and the results are on a par with the full tomtom device.
mikechannon said:
Actually I'm not so sure we have defined the problem accurately here.
Examining the signal from the GPS shows some interesting info.
1
A satellite is locked onto for perhaps only one or two seconds at a time.
2
Several satellites can achieve a lock but out of these a few will be lost every few seconds
3
New satellites are also acquired every few seconds.
The Result
If you are in the presence of many satellites then there is a constant dropping of some and locking onto others. This leads to no problems as there are always a few satellites locked on and data flow is smooth.
BUT
If you are in the presence of only say 2 or 3 satellites it is possible to drop these two or three (as indicated above), but no new ones are acquired. In this situation there will be a few seconds before the first 2 or 3 lock in again. Result a gap in data flow to your GPS software.
Meaning
The Internal GPS is not polling data in bursts. In other words you cannot turn up the frequency of data polling (possible baud rate adjustment maybe). The data is continuous but if there are too few satellites then there can be gaps where it drops some satellites and does not lock others.
There are various applications that can show this behaviour graphically but tomtom shows it well on the satellite view screen.
Compared to external GPS satellite locks this works in a strangely different way. You will see the bars jumping around from a lock on this one to that one continuously. Only a problem as I say when there are only a few satellites in sight.
Mike
PS - I cannot see the advantage of GPSGate in this particular situation as it is due to momentary periods when no satellite is detected.
Having said all of the above, I find the GPS perfectly adequate for general use. Perhaps if I need spot on plotting data then it might be weak. However if I need that unusual level of accuracy I would not use my phone to do it. I regularly use mine in place of my car's tomtom and the results are on a par with the full tomtom device.
Click to expand...
Click to collapse
Ok, I believe that it is time to explain a little bit how GPS works.
The GPS satellites are transmitting their position rapidly. However, due to homeland security issues (US did not want to allow anyone to place a receiver in a jet fighter or a missile) civilian GPS receivers are limited to aquire position every 1 second only. This is not a problem for a normal user even for civilian aviation. Thus, when you look at the NMEA stream, you will see it coming in bursts and not as rapid as normal data. Since GPS strings are quite short, it is good enough for any navigation system.
Number of satellites aquired is not an indicator to anything. Like any RF system, the engineers can tweak the noise level so that it will look to you that you are receiving X amount of satellites, the signal is on the air anyway.
What is important though is the position of the satellites. the closer to the horizon, the less useable that satellite is to calulate the position. Therefore receivers are taking the best located satellites into account and ignoring others even of they are recieved. Valid fix (position) is aquired by at least 3 satellites for 2D (X,Y) and 4 or more for 3D (with elevation).
Result is that as a user, you should not bother too much looking into the stream or number of sattelite in use as long as you can get a valid fix. The important and effective elements are hidden from the user: number of transsistors in the GPS chipset, quality of antenna etc. User can just evaluate the overall preformance.
As I wrote above, the Kaiser integrated GPS surprised me for superb preformance. I just arrived this week from Israel to Germany and could get a fix as soon as I left the underground garage. I did not loose GPS signal even once since I started using the device. That includes forests and dence city centers. Real good job by HTC here.
This is the problem i am facing:
Im using MapKing with Hong Kong 2007 maps. Getting a fix is no problem. I can normally get a fix in about 10-15 secs. When i check the status page I will normally have a connection to 5-7 satelites.
The problem is that the icon does not move smoothly when i travel. In map king your position on the map is represented by a small car icon. It jumps from location to location every 3-5 secs but does not smoothly move along. Can someone please tell me if this is the case with tomtom as well? Maybe it a problem with mapking?
phame said:
This is the problem i am facing:
Im using MapKing with Hong Kong 2007 maps. Getting a fix is no problem. I can normally get a fix in about 10-15 secs. When i check the status page I will normally have a connection to 5-7 satelites.
The problem is that the icon does not move smoothly when i travel. In map king your position on the map is represented by a small car icon. It jumps from location to location every 3-5 secs but does not smoothly move along. Can someone please tell me if this is the case with tomtom as well? Maybe it a problem with mapking?
Click to expand...
Click to collapse
It is a Mapking problem and you should contact their support. Does not happen to me with Destinator, TomTOm and Ozi.
Ok, there is no point to argue, if you really find yourself having problem with GPS update lag, then give it a try. No harm indeed...
In HK, there are people the validity of the work around. GPS proxy might also work as well( i think it is the same principal) just i wasn't aware of this good free software before hand..
http://www11.discuss.com.hk/viewthread.php?tid=5329804&extra=page=2
(u need an account and some chinese word knowledge)
trueman12345 said:
Ok, there is no point to argue, if you really find yourself having problem with GPS update lag, then give it a try. No harm indeed...
In HK, there are people the validity of the work around. GPS proxy might also work as well( i think it is the same principal) just i wasn't aware of this good free software before hand..
http://www11.discuss.com.hk/viewthread.php?tid=5329804&extra=page=2
(u need an account and some chinese word knowledge)
Click to expand...
Click to collapse
Quite agree it's worth trying, and the application has other uses too.
Mike
FYI: I got GPS to work easily by installing GPSViewer, opening COM4/4800baud and getting located. After that, using Google Maps was a breeze; total "trick" took me about 1 minute to figure out which is way quicker than some other workarounds on the internet.
I was driving with iGuidance for about 1 hour this morning and I'm seeing different behavoir for this bug. iGuidance also has an excellent GPS signal viewer, mine was showing 8 out of 8 sattellites, all green, all the time (they turn red when not receiving signal from a sat). My map was moving about once per second or slightly faster. The program only paused once after about 30 minutes into the trip, for about 20-30 seconds. The iGuidance program's moving arrow's color also changes color based on signal quality of the combined sattelite lock, Green for good 3D mapping, Yellow for 2D when there are minimal sats for navigating, and Red for no signal data. During this pause the arrow went Red to indicate no data.
This seems like a bug to me.
Hello,
In comparing the altitude reading of the internal GPS with two other GPS recievers (one WAAS enabled) and in knowing the true altitude (at several airports), it seems that the At&t Tilt is always reading about 100-120 feet low compared to the other two receivers and the actual altitude. Have any others noticed this?
I have never seen an accurate or high reading, it has been lower than the the other recievers at every location and test that I have done. I upgraded to the new AT&T HTC Rom as soon as I recieved the phone and do not have data before this upgrade.
Thanks,
John
Docj_Aero said:
Hello,
In comparing the altitude reading of the internal GPS with two other GPS recievers (one WAAS enabled) and in knowing the true altitude (at several airports), it seems that the At&t Tilt is always reading about 100-120 feet low compared to the other two receivers and the actual altitude. Have any others noticed this?
I have never seen an accurate or high reading, it has been lower than the the other recievers at every location and test that I have done. I upgraded to the new AT&T HTC Rom as soon as I recieved the phone and do not have data before this upgrade.
Thanks,
John
Click to expand...
Click to collapse
Sorry I only use the GPS for directions, but, what program are you using to get your reading? 100-120 feet of difference seems like a program issue. Tilt GPS should not be that inaccurate. Maybe you could try a different program and see if you get a different result.
I have used many different programs and they all give the same altitude (the same as that contained in the NMEA string). VisualGPS, NoniGPS, GPS Tuner, GPS Utilities, and others all give the same; hence the confusion.
John
Docj_Aero said:
I have used many different programs and they all give the same altitude (the same as that contained in the NMEA string). VisualGPS, NoniGPS, GPS Tuner, GPS Utilities, and others all give the same; hence the confusion.
John
Click to expand...
Click to collapse
I have seen the same results using a myriad of gps software. I dont have a fix either, just confirming your observations.
Has anyone either noticed this error, or can verify that their unit is in fact agreeing with other gps receivers?
I called tech; they were not much help.
I have the same problem.. I fly a powered paraglider, and I want to plot my path on Google Earth. All of the points end up being below ground, unless I am very high in the sky
I have a 8925 stock rom with APIC on it, I have matched the readings on it to a Garmin 430, now keep in mind the antenna on the 8925 does not have the same sensitivity nor size/location as the 430s. I would not shoot a approach with my 8925, though it's readings (GS, ALT, HDG) match up to the 430.
Also does anyone know if the 8925 can be WAAS enabled?
Altitude calculation is an issue with commercial GPS devices. You can read more here http://www.gpspassion.com/forumsen/topic.asp?TOPIC_ID=10915
not true, aircraft shoot GPS approaches all the time, a cat II approach has a minimum decision height of 200', so if it is common for a WAAS GPS to be that off, planes would be lawn darting left and right.
That said I have noticed that the vertical navigation accuracy of my non-WAAS 8925 improves greatly when it is at altitude (500' + AGL), now if it was WAAS I would be accurate at low altitudes as well at any airports that supports a GPS approach.
From wikipedia:
The elevation display from the internal GPS will be inaccurate due to it using the WGS-84 Datum which can deviate from mean sea level in the range of +85 to -107 meters. The main reason for this is because the internal GPS uses the data it receives and references it to the Ellipsoid model of the earth which is a perfect shape. Standalone GPSes use the Geoid model of the earth which is lumpy version of an Ellipsoid. Then they apply a correction value based on the present location to supply the elevation.
Click to expand...
Click to collapse
This makes it sound as if it's a hardware problem that cannot be fixed.
Dave
right from the wiki for the htc tilt wikipedia site.... read through but your info will be in the last paragraph of this read.
GPS Compatibility
Users of this phone have successfully installed and used other GPS map software applications (such as ALK Technologies CoPilot Live 7, DeLorme Street Atlas USA 2009, Fugawi, Garmin Mobile XT, Google Maps Mobile, iNav iGuidance, Intrisync Destinator, Microsoft Live Search Mobile, TomTom, Tracky, and VisualGPS BeeLineGPS), which are either free or cost nothing beyond the original purchase price. The map applications are compatible with the built-in GPS receiver, provided users set the appropriate COM port for the map application. The built-in GPS receiver was intended by some wireless providers to be used preferably with Telenav, which is a service that charges users monthly fees or fees based on the amount of downloaded map data. It should be noted that Telenav can only provide map data in areas where applicable cellular phone services are available and that users must have a data plan with their wireless providers.
The GPS may not activate when the phone is used indoors (or without access to clear sky) or if the person is walking very slowly (< 1 mile/hour).[citation needed] External GPS antenna connection provision is provided for clear signal reception. It is important for the GPS to be activated for the various functions in the GPS software to be activated and used properly.
The elevation display from the internal GPS will be inaccurate due to it using the WGS-84 Datum which can deviate from mean sea level in the range of +85 to -107 meters.The main reason for this is because the internal GPS uses the data it receives and references it to the Ellipsoid model of the earth which is a perfect shape. Standalone GPSes use the Geoid model of the earth which is lumpy version of an Ellipsoid. Then they apply a correction value based on the present location to supply the elevation.
Click to expand...
Click to collapse
I have an AT&T Tilt with WM 6.1. The GPS reports location but fails to indicate speed and direction. So, programs like Google Maps and Windows Live Search work ok, but programs like Turbo GPS and GPS Utilities report location, but have no data for speed and direction. Is there a way "turn on" the reporting of speed and direction from the GPS for 3rd party programs?
this isn't how GPS works.. the GPS receiver just reports back the location every second. speed and direction are calculated by the program
r34p3rex said:
this isn't how GPS works.. the GPS receiver just reports back the location every second. speed and direction are calculated by the program
Click to expand...
Click to collapse
That's what I thought. Michael, the author of TurboGPS, corrected me. He examined the "raw log" of what the hardware gps was reporting on my tilt and it was reporting null strings where the speed info is supposed to be returned to the program from the hardware gps.
I assume AT&T disabled that function of the hardware gps to force purchase of the Telenav subscrition.
I read a story somewhere that said If it only have three GPS satellites it can only locate you on a 2D pane. To get Height it would need a 4th satellites, and thus 3d location.
Maybe the lock isn't strong enough to calculate to speed.
Do you know how many satellites you are seeing and receiving from when you're locked?
Maybe disable AGPS? I've heard that messes with the NMEA output.
Now please no groaning when you see this topic. I know the GPS has been hammered to death on these forums; this post is my vein attempt to see if one particular area of interest of mine has at all moved forward.
(let's also side-step the whole "does your GPS lag?" issue here too!)
(..and, for clarify, I'm referring to AGPS as in the use of the mobile phone network to 'assist' positioning by use of triangulation in areas of poor/no GPS reception, and NOT the use of QuickGPS to download current sat. info in an attempt to get a quicker initial fix)
I used to use TomTom Navigator v7.450; it worked (of a fashion! ) although one specific thing that never worked was that whenever AGPS was enabled (using AdvancedConfig or similar) TomTom would get a signal and then immediately drop it again.. on/off on/off etc.. the fix being to disable AGPS.
I must admit I'm suspicious about HTC having their stock ROMs with AGPS disabled by default - especially as this was initially a 'selling point' of the device and part of the sales blurb ("not only does it have GPS but really good GPS using AGPS".. oh the irony!) - have they themselves ever got it to work?!?!
Now TomTom Navigator v7.910 is out (have just installed it myself, currently waiting for an updated map to download). I have seen it muted that this now works with AGPS on the Diamond or maybe the Pro (ie. someone reports the above bug, yet claims it now works having moved to v7.910). Can anyone else confirm this? More importantly, can anyone confirm AGPS has given the Diamond any GPS-related benefit what-so-ever?? (ie. great if it doesn't stop TomTom working anymore, but does it actually improve it like it should?).
I'll of course try it out myself later today or over the weekend and report back.
Hope this makes sense.. cheers.
just tried TomTom 7.910 (9185) with AGPS enabled, and cant say i noticed much difference.
seems the same now with it enable or dissabled. Cant be sure tho, havent done a long journey yet.
Will update later/tomorrow.
mugglesquop said:
just tried TomTom 7.910 (9185) with AGPS enabled, and cant say i noticed much difference.
seems the same now with it enable or disabled. Cant be sure tho, haven't done a long journey yet.
Will update later/tomorrow.
Click to expand...
Click to collapse
Thanks for taking the time etc.
Interesting, because..
I've just taken a wonder outside and found I'm still getting the signal constantly being lost bug (looking at the screen that shows the sat. bars I have a good signal for a few seconds, then this goes and 'No GPS device' is displayed, then good signal back again and so on).
On this Diamond I'm using ROM 1.93.401.2 the the supplied radio (1.0.25.05), as I suspected this 'improvement' (potentially) noticed by you/others is more likely a result of a ROM/radio update and not a TomTom software update (guessing this AGPS bug isn't the first thing you try after flashing is it?).
Hmm..
nb. I'm using the exact same version/build of TomTom as you
hmmm... yeh, i'm going on a 60+ mile journey later, so will have a play.
Using Dutty's 3.4 ROM and Radio is BS14...
I thought that the whole point of AGPS is so you could help you get a GPS fix when indoors. Which I always thought was an unusual selling point when the entire purpose of GPS software is to help you find your way in the outdoors. Perhaps it could be more useful for those new tagging services that are popping up.
Anyhow I've been running a fairly recent version of iGo8 using Dutty's Rom 3.3 and 3.4 (both with that new radio).
With AGPS turned off, GPS signal is quickly attained and holds strong outdoors. Nothing indoors, naturally.
With AGPS turned on (via Duttys "AGPS Settings" utility), GPS signal is as quickly attained and flickers fully on then fully off, repeating constantly. When indoors, nothing at all.
So, with iGo8, AGPS seems to be a non-runner.
By the way, I once read that AGPS has to be configured to your particular mobile provider. Perhaps that's the issue?
Same here, with a-gps enabled signal drops constantly
after my journey yesterday, had the same problems as above.
tried with TomTom 7 and iGo8
I've never had any problems with GPS apart from slow getting a moving fix when the unit is physically very hot.
The main benefit of AGPS for me is that you can get your location on Google Maps within 1500m or so without enabling GPS.
It also proves A-GPS works.
ben cole said:
I've never had any problems with GPS apart from slow getting a moving fix when the unit is physically very hot.
The main benefit of AGPS for me is that you can get your location on Google Maps within 1500m or so without enabling GPS.
It also proves A-GPS works.
Click to expand...
Click to collapse
Hmm, I think this is thanks to googles effort, not AGPS... Google uses Google Gears API which can position you by using basestations and SSIDs.
AGPS is correcting/updating the GPS data with actual almanac data sent from you mobile provider...
Pitchb3nd said:
Same here, with a-gps enabled signal drops constantly
Click to expand...
Click to collapse
Same for me, anyone being able to use TomTom and AGPS without losing signal periodically?
ben cole said:
I've never had any problems with GPS apart from slow getting a moving fix when the unit is physically very hot.
The main benefit of AGPS for me is that you can get your location on Google Maps within 1500m or so without enabling GPS.
It also proves A-GPS works.
Click to expand...
Click to collapse
Yeah Google Maps does this on its own without having AGPS enabled on the Diamond. I believe AGPS is supposed to be more accurate than 1000m - 1500m though.
Oh and I believe the way that Google Maps gets its position depends on your mobile provider. I used to get the message "your location is not available" constantly on my network but one day (simultaneously as the iPhone was released in my country), the location was available. So I believe that the network flicked a switch for this technology to work.
AGps and TomTom
Hi,
agps have need to run to:
1) Carrier to inform MobilePhone here is (Is a Base Station Issue)
2) Public information about position
On mobilephone if is enable i think is need to have different information, and tomtom have old pattern to process agps information.
With googlemaps have new process and can use.
With my diamond agps run (googlemaps)
Cityhunter71
Please, don't mix the Google technology and A-GPS. They have nothing in common.
Google maintains their own privately held database of GSM-cellids which GMM can query to determine your position based on the current cellid.
A-GPS is a technology where the GSM-basestation itself receives GPS-satellitedata and relays it to the device. With this additional data, the GPS-receiver in the device is supposed to achieve a faster fix.
Have fun!
a-gps works with 7.450
i remember once that it was taking forever for the satelites to be found yet is was updating my postion on the map constantly via a-gps (which im sure was enabled by default in stock rom as ive never changed it)
a-gps is useful inside because you usually have your phone with you and to find a route, you need gps
Apologies for my erroneous post.
I realised my error today when I installed Google Maps on an ageing Blackberry I had unlocked to play with.
Started it up and lo and behold there was my location....thought I'd better head back here to suffer my shame ...LOL
Thanks for the input guys.
So - in summary:
Even with later ROMS / radios / software applications, there is still yet to be seen any benefit from the Diamond (theoretically) having an A-GPS capability.
RUBBISH!!
I personally subscribe to the theory that there is a missing link between the A-GPS driver type software and an info feed from the likes of the network operator, ie. it's all very well it picking up info on the network but without a back-end database to translate this it's useless.
As far as purpose goes.. I personally think A-GPS sounds on paper to be a great idea. Not a replacement for GPS, nor to be used exclusively indoors, but a good aid/starting point. For example, if I'm sitting in an unfamiliar office in London and wanted to use TomTom to navigate me a route to where I want to get to, A-GPS could provide TomTom with a rough starting point. Similarly, I often find myself launch a nav program (when I'm lost!) and standing there for up to 5 mins waiting for a fix.. at least this would give me an approximation from which I could probably work out myself where I was from looking around me. In my mind when you first fire up TomTom on the Diamond A-GPS should simply put you in the right postcode and start doing its stuff while the GPS seeks out its signal, and not still show me as being either at Home or its last known destination. But in any event - it seems not to work!! Bugger!!
I thought that aGPS was also to help hold a GPS signal when in tunnels, canyons, heavy forest cover (ie.Redwoods in this area, many tower to well over 300 feet!) or any situation where the signal from the satellites may be impaired, or even blocked completely.
Im running Duttys 3.5 and with AGPS on I will get a signal for 10 seconds, then it goes for a second, then back for 10. then gone. Turned AGPS off and all is well.
I can confirm that AGPS does work, some parts here in Finland it works and someplaces it does that on off thingy. once when I was just playing with my tomtom it got signal where it would never get it without it. but mostly here it doesnt work properly so i disable it.
But in Helsinki (larger city) it works properly and helps getting signal fast beneath tall buildings.
But yeah it doesnt work in my hometown so its kinda rubbish here.
Maybe it has something to do with how new are nearby cell towers or something. dunno
In Trondheim, Norway it worked with Telenor and gave me a signal indoors, but when I use it together with TomTom the signal gets lost periodicly, really really annoying since "everything" is already there. Probably just something with the co-operation with the regular GPS or something?
I think i got it to run.
I use tt7.910 on diamond with htc 1.93 dutch rom
My mobile provider is mobistar.
I can get a lock inside, tough it's slow(ie not as fast as outside).
When I fire up tt7 the almanac data is showing in the satelite screen.
reg settings are:
Code:
GPRSConnection: Orange World
GpsMode: 4
Network: Orange World
ServerIP: 194.51.71.138
ServerPort: 7275
ServerUrl: agps.orange.fr
GPS Questions that I haven’t seen in other threads.
Along with many of you I'm trying to get my GPS to obtain a fix faster.
I have a Tilt (8925 / TYTNII) / WM6.1 with Garmin Mobile XT (no data plan just wifi). I’ve had an issue for the past year with the GPS not locking on for up to fifteen minutes even though it appears to see up to nine good satellites. HTC replaced the mother board which includes the Qualcomm GPSone chip. This corrected most of the problems but at times it still takes a long time to lock on even though it shows satellites with good signal strength. QuickGPS comes loaded on the phone yet has no effect on how long it takes to lock on. It’s my understanding that the satellite locations are loaded in an almanac on the phone. Since this data changes it must be refreshed on a regular basis for the chip to lock on quickly. I have several questions.
1) Is the almanac / ephemeris data stored on the GPSone chip’s memory (if it has any) or does it reside in the phones memory? If it’s on the phone can it be read?
2) Does each satellite transmit at a different frequency and does the GPSone chip scan these frequencies looking for a satellite that can download the latest almanac and ephemeris data?
3) QuickGPS doesn’t seem to make any difference on my phone. Is this program what’s called “assisted GPS”? If so does QuickGPS update the GPSone’s ship data or the GPS software’s data you are using such as Google maps or Garmin? I assume it’s the GPSone’s data because the chip must send a “sentence” to your GPS software telling it that the chip has locked on to enough satellites to provide navigation. Until this happens the GPS software just waits or times out. When I look in the registry I see that enableAGPS dword is set to 00000000. Wouldn’t this have to be a one for assisted GPS to work? I tried setting it to a 1 but it didn’t make any difference.
4) I download data using QuickGPS (via wifi). How can I tell that the data is for my area or if it is being used by the GPSone chip? It’s using 193.253.42.109 which is a site in California called Geo Information. Is the almanac information global? In other words does QuickGPS provide information on all GPS satellites in every download? If I do a soft reset and then run QuickGPS and then start Garmin I don’t see any satellites for about two minutes. It then appears to load almanac data from the first satellite it sees and then a bunch of satellites pop up all at once. That’s why I don’t think QuickGPS is helping.
5) This seems to be a huge problem with our phones. Could someone write a script to poll the GPSone chip say every two hours which would in turn refresh the GPS data so that whenever we need to use the GPS it would be doing a warm start rather than a cold?
Thanks for any insight. I’m lost in more ways than one.
Frank
Im not sure whats causing ur issue! but i never thought quickgps helps. its always the usual slow gps connectivity in my phone. just thought i will add my 2 cents...
Get this http://www.visualgps.net/VisualGPSce/default.htm program. Go outdoors (not between tall building) in an open area. Run VisualGPSce, see if it locks within 2-3 minutes. Once it locks, you can try other programs.
Make sure you GPS is set to com4 and preferably 38400 bps.
GPS coverage is not so good inside the buldings. Wood buildings are fine. Buildings and cars with UV protection and tinted glass are trouble. Also concrete walls/roof are another trouble.
Also to add, QuickGPS never helped me.
FrankCB said:
GPS Questions that I haven’t seen in other threads.
Along with many of you I'm trying to get my GPS to obtain a fix faster.
I have a Tilt (8925 / TYTNII) / WM6.1 with Garmin Mobile XT (no data plan just wifi). I’ve had an issue for the past year with the GPS not locking on for up to fifteen minutes even though it appears to see up to nine good satellites. HTC replaced the mother board which includes the Qualcomm GPSone chip. This corrected most of the problems but at times it still takes a long time to lock on even though it shows satellites with good signal strength. QuickGPS comes loaded on the phone yet has no effect on how long it takes to lock on. It’s my understanding that the satellite locations are loaded in an almanac on the phone. Since this data changes it must be refreshed on a regular basis for the chip to lock on quickly. I have several questions.
1) Is the almanac / ephemeris data stored on the GPSone chip’s memory (if it has any) or does it reside in the phones memory? If it’s on the phone can it be read?
2) Does each satellite transmit at a different frequency and does the GPSone chip scan these frequencies looking for a satellite that can download the latest almanac and ephemeris data?
3) QuickGPS doesn’t seem to make any difference on my phone. Is this program what’s called “assisted GPS”? If so does QuickGPS update the GPSone’s ship data or the GPS software’s data you are using such as Google maps or Garmin? I assume it’s the GPSone’s data because the chip must send a “sentence” to your GPS software telling it that the chip has locked on to enough satellites to provide navigation. Until this happens the GPS software just waits or times out. When I look in the registry I see that enableAGPS dword is set to 00000000. Wouldn’t this have to be a one for assisted GPS to work? I tried setting it to a 1 but it didn’t make any difference.
4) I download data using QuickGPS (via wifi). How can I tell that the data is for my area or if it is being used by the GPSone chip? It’s using 193.253.42.109 which is a site in California called Geo Information. Is the almanac information global? In other words does QuickGPS provide information on all GPS satellites in every download? If I do a soft reset and then run QuickGPS and then start Garmin I don’t see any satellites for about two minutes. It then appears to load almanac data from the first satellite it sees and then a bunch of satellites pop up all at once. That’s why I don’t think QuickGPS is helping.
5) This seems to be a huge problem with our phones. Could someone write a script to poll the GPSone chip say every two hours which would in turn refresh the GPS data so that whenever we need to use the GPS it would be doing a warm start rather than a cold?
Thanks for any insight. I’m lost in more ways than one.
Frank
Click to expand...
Click to collapse
1. Stored in phone memory, and yes it can be read.
2. A GPS receiver calculates its position by precisely timing the signals sent by the GPS satellites high above the Earth. Each satellite continually transmits messages containing the time the message was sent, precise orbital information (the ephemeris), and the general system health and rough orbits of all GPS satellites (the almanac). The receiver measures the transit time of each message and computes the distance to each satellite. Geometric trilateration is used to combine these distances with the location of the satellites to determine the receiver's location. The position is displayed, perhaps with a moving map display or latitude and longitude; elevation information may be included.
3. QuickGPS is not Assisted GPS. QuickGPS downloads the latest satellite positions to help with a faster initial GPS fix. Assisted GPS uses your cell-phone location through cell-tower triangulation to provide a location just like a GPS receiver would. Usually not as accurate.
4. QuickGPS downloads a global catelog. The amount of satellites used for GPS aren't so numerous that it needs to download just the ones in your area. It basically downloads a text listing of all the available GPS satellites.
5. Have you tried flashing a new radio to your device? This can make a world of difference in GPS fix acquisition, especially in different areas.
Also, have you read this?
Thank you for all the info. I just found this article
I'm still not sure why QuickGPS isn't helping. While on my quest for GPS information I found this article. It answers a lot of questions. Thanks also for the link to the GPS thread. I had read it before but it didn't answer the questions I posted.
http://arstechnica.com/gadgets/news/2009/01/assisted-gps.ars
my Tilt locks onto 4 or 5 satellites within 10-20 seconds, usually faster. I've never had a problem. It even locks onto 2 satellites when I'm in my apartment. I use quick GPS, updated via WiFi, but I haven't updated it for a couple weeks.
I'm running wm6.5, 1.7x radio.