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Is this function in our Kaiser? I've enable it from the Kaiser Tweak but today i tested it when i was in a tunnel....it did not work at all and the tunnel was 4 KM long....it should have had enough time to get a fix if it was working.
Is the Assisted GPS what i think it is?
How do you expect to get a GPS fix in a tunnel???
AGPS is basically what the QuickGPS app. does: it downloads sat. data (satellite locations) via a network connection from a server, so that TTF (time to fix) is reduced, since the device doesn´t have to download above data from the satellites themselves - which is slow....
Hope I was not too unclear, doing a search will give you much more and detailed info about how GPS works......and it doesn´t in tunnles....
As mentioned above, the AGPS uses server information (via cellular network) to locate the GPS satellite for a quicker fix and hash conditions. For a 4KM tunnel, I'm sure that your phone would have lost both GPS and network signal.
michi123 said:
How do you expect to get a GPS fix in a tunnel???
AGPS is basically what the QuickGPS app. does: it downloads sat. data (satellite locations) via a network connection from a server, so that TTF (time to fix) is reduced, since the device doesn´t have to download above data from the satellites themselves - which is slow....
Hope I was not too unclear, doing a search will give you much more and detailed info about how GPS works......and it doesn´t in tunnles....
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Click to collapse
Thats correct, there are som applications that tries to estimate where in the tunnel you are when the fix is gone. But I suppose this is a function of the application and not the GPS hardware
I stand partially corrected........ http://en.wikipedia.org/wiki/Assisted_GPS
michi123 said:
How do you expect to get a GPS fix in a tunnel???
AGPS is basically what the QuickGPS app. does: it downloads sat. data (satellite locations) via a network connection from a server, so that TTF (time to fix) is reduced, since the device doesn´t have to download above data from the satellites themselves - which is slow....
Hope I was not too unclear, doing a search will give you much more and detailed info about how GPS works......and it doesn´t in tunnles....
Click to expand...
Click to collapse
Which is why the title is "Assisted GPS".....I've done some search on AGPS and it's suppose to use the cellular to still get a fix when in the tunnel. Well....i read it sometime ago way before Kaiser was out and this was actually one of it's talked about feature in Kaiser. Using the Kaiser Tweak, one can enable this feature but i've tested it today in the tunnel with strong cellular signal, the GPS is dead until i came out of the tunnel.
I guess it also has to be supported by the particular program. Many TomTom PNAs have a dead reckoning mode which shows your position in a tunnel based on your "entry" speed for about 30 seconds, than the position freezes in the tunnel. Now that of course has nothing to do with AGPS, but it´s a way of overcoming temporary signal loss.
Best way would be to have an inertial sensor built into the phone like in fix-mounted car-navs......but then again, that would be overkill....
You have to remember that the Assisted GPS (Cellular network mode) relies on the fact the network itself supports the feature. I know most in the UK don't have it turned on in general use. They only allow it to be used by emergency services and the likes.
Perhaps that's the same in your country?
the_ape said:
You have to remember that the Assisted GPS (Cellular network mode) relies on the fact the network itself supports the feature. I know most in the UK don't have it turned on in general use. They only allow it to be used by emergency services and the likes.
Perhaps that's the same in your country?
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Click to collapse
Probably so.....oh well....it was worth a try
Thanks guys for the input.
Hi all,
I am using Navigon6 for navigation but while driving in a tunnel navigon says "you have reached the destination" after the tunnel it starts navigating as usual. I now activated "assisted GPS" with the Kaiser Tweak but now? How does it work now? What do I have to do?
Thanks
Michael
micha2802 said:
Hi all,
I am using Navigon6 for navigation but while driving in a tunnel navigon says "you have reached the destination" after the tunnel it starts navigating as usual. I now activated "assisted GPS" with the Kaiser Tweak but now? How does it work now? What do I have to do?
Thanks
Michael
Click to expand...
Click to collapse
You do nothing! Some people say the tweak works and some don't. It seems to have worked for me. I don't lose signal at this road will lots of trees now (I used to lose signal before I had this tweak applied).
Hi, so I tried the Kaiser with activated A-GPS and Navigon6. As I said I had the problem that Navigon gave the message "Destination reached" while driving through a tunnel. I expected that Navigon, because of a signal from A-GPS, won't bring these message. In the first moment I was happy because the Icon didn't turn to red in a tunnel but then there was the message again. But there is another problem, with activated A-GPS there seems to be some kind of signal (icon doesn't turn red) and because of this Navigon doesn't start routing after the tunnel. So it seems that A-GPS doesn't work together at least with Navigon6. Any ideas?
Cheers
Michael
Hi
I expected that Navigon, because of a signal from A-GPS, won't bring these message.
Click to expand...
Click to collapse
As far as I know A-GPS (QuickGPS on Kaiser) is just for getting initial fix for GPS applications. This helps avoid the initial delay in getting your location, after that it will perform exactly the same.
Regards
Phil
Hi Phil,
OK, I understood what A-GPS does but Navigon should proceed navigation after a tunnel (when GPS signal is back) again even A-GPS is turned on or not?
Cheers
Michael
PhilipL said:
Hi
As far as I know A-GPS (QuickGPS on Kaiser) is just for getting initial fix for GPS applications. This helps avoid the initial delay in getting your location, after that it will perform exactly the same.
Regards
Phil
Click to expand...
Click to collapse
PhilipL said:
Hi
As far as I know A-GPS (QuickGPS on Kaiser) is just for getting initial fix for GPS applications. This helps avoid the initial delay in getting your location, after that it will perform exactly the same.
Regards
Phil
Click to expand...
Click to collapse
QuickGPS is indeed a form of Assisted GPS used to quick the initial fix. However, he is talking about the Assisted GPS tweak for use _while_ navigating. It already requires a fix and lets your phone keep on tracking when going through tunnels or when satellite reception is too low. If it works by simple extrapolating direction and speed or uses some sort of GSM tower triangulation technique nobody seems to know. All we know is that the signal doesn't get lost so quickly with it As always with stuff like that, YMMV.
Are we all sure about the definition of "Assisted GPS" - 'cos QuickGPS is not my understanding of it and neither is extrapolating position using GSM tricks when the GPS signal fails.
As far as I am concerned, Assisted GPS is the term to cover a variety of techniques aimed at improving the accuracy of a fix over and above what is possible from just the received satellite signal. WAAS (EGNOS in Europe) is the most common way of doing this but on a device with a built in data connection there are other options. The basic idea is that a variety of factors including interference to the satellite signals as they come through the ionosphere and GPS satellites being out of adjustment can reduce the accuracy of the calculated location. With Assisted GPS, there are a number of base stations dotted around the world at locations which have been very accurately determined by traditional surveying techniques. GPS receivers at each of these locations are continuously calculating their GPS based locations, comparing them with the known, correct location and generating hints in a defined format which other GPS receivers can use to improve the accuracy of their calculations.
The issue then is how to get these hints out in near real-time to the remote GPS receivers. WAAS and EGNOS use dedicated satellites to transmit them back to earth, but these only cover the US and parts of Europe. With a GPS in a mobile phone, you obviously have the possibility of using the data channel to distribute the correction data - a lot cheaper than launching satellites. The EGNOS correction data is already published on their web site - not sure about WAAS - I tend to assume that enabling Assisted GPS on a Kaiser just sets the receiver to downloading the correction data stream off the internet...
Martin
No, that's not Assisted GPS. That's Differential GPS.
Assisted GPS is designed to allow GPS to perform in areas with poor satellite reception, augmenting the fix with information on nearby cell towers (which have known locations and ranges). Also, in most situations, A-GPS also means that the GPS pseudorange processing is offloaded from the phone to the tower (to allow for E911 on phones with insufficient CPU to calculate a GPS fix on their own), but I'm assuming this part of A-GPS is not coming into play here.
Some users from the pocketnavigation forum have the same Problem with the Kaiser/GPS-Chip. It seems to be a really big software/hardware bug.
By loosing the signal in the tunnel the gps chip stops to send any information to the Navigon-software. That's the problem: The required systemtime for further navigation is missing.
So Navigon tells you: You've reached your destination.
Any Firmwareupdates for this Problem?
Greetings
As far as I understood it, QuickGPS is downloading the satellite almanac from the internet, instead of getting it through the GPS. A GPS which has not been turned on for a while will get this almanac even without internet connection, but it takes about 15 minutes to download it (happens automatically in any GPS unit). Getting it from the internet saves you these 15 minutes, but if you have used your GPS recently for more than a 15 minutes period, QuickGPS should not make any difference.
The almananac for the GPS satellites is like a sun or moon almanac, just for satellites instead. This means that if you have a current almanac, and your GPS knows your rough position, then the almanac will tell the GPS where it should expect to see the satellites. This includes which of the satellites are visible on a given position on the earth (roughly around a third of them), and at what azimuth and elevation. GPS satellites are orbiting the Earth in intervals of just under 12 hours in certain orbits, intercepting the Equator at 55 degree angles (which means that they will cross 55 deg North/South when they are closest to either pole). Since they are more than 20000 km out, this is not a problem if you are actually on or close to either pole, but it means that you will not see satellites right above you at either pole. WAAS satellites are geostationary (which means they can only be somewhere over Equator at about 36000 km orbit), and these satellites do not transmit normal position and time information like the other satellites (SVs) in the GPS system, but precision and integrity information. Put in other words, they tell the GPS receiver 1) Is the signal in your area good or bad and 2) What vector to correct your measured position in whatever area your GPS says you are in. Similar for LAAS units, although they differ in being local area only but on the other hand, more precise. LAAS units are called pseudolites, because they act almost like satellites, though they are really not. For aviation, LAAS enables precision auto-landings in "zero weather" for the same reason, but since the LAAS station is on or close to the surface of the Earth, it only works when in line-of-sight of it.
The problem I am experiencing is if I turn my GPS off and move it a couple of hundred of miles and then turn it on again. This is usually when I am flying, and as we all know, the battery of the Kaiser is not really built for powering the unit for very long! When I turn the GPS on after for intance an hour or so, it still assumes the original position, and it will sometimes get a lock on on or two satellites only, trying desparately to maintain that position. Knowing how the GPS satellites interpolates via a time-shifting technique, I can see why this happens, as it gets a false fix. Aviation grade GPS systems will never lock on to anything less than 3 satellites for a 2D fix, and prefers 5 or 6 satellites minimum for integrity reasons (called RAIM).
What I think is the real problem is that these end user GPS systems for road use have to be more sensitive, so they can be used behind shielded windows and poor reception areas in buildings etc. Trees with many leaves can be an issue also, although clouds are no factor in this equation. Sunspots can blind the system completely if they are strong enough, and that is why eLORAN is an update to the LORAN-C system which is currently being considered for backup purposes mainly.
So, my Kaiser and other end user GPS units will be less restrictive for a good quality fix, and accept second guessing the position, where as aviation and other critical uses of GPS have to have a good position.
We need a GPS utility for the Kaiser GPS to carry out a position reset so it can do a new fix.
Hi guys,
OK I understood what A-GPS is but there is still the issue that Navigon really stops Navigation if the signal is lost when A-GPS is turned on.
If A-GPS is turned of there is also the message "destination reached" but after the tunnel it starts navigating again. Any idea on this?
Cheers
Michael
micha2802 said:
Hi guys,
OK I understood what A-GPS is but there is still the issue that Navigon really stops Navigation if the signal is lost when A-GPS is turned on.
If A-GPS is turned of there is also the message "destination reached" but after the tunnel it starts navigating again. Any idea on this?
Cheers
Michael
Click to expand...
Click to collapse
It sounds more like a bug in Navigon more than anything, check for updates on their site.
A-GPS for Mobile devices as said by some in this thread, extrapolates from the last vector information of the GPS using also information of cell location (in some countries this info is not available due to Gov restrictions) and inserts new data available for any app when signal loss is present from the GPS unit, thus reducing the 'Lost satellite reception' on your app. On WM devices, we are not looking directly at the GPS output but at a 'handler' at com4 able to supply GPS information to more than one app at a time. This is where A-GPS and QuickGPS insert their data when needed. A-GPS just directly inserts nomal NMEA data stream whereas QuickGPS sends the latest Ephemeris data it has downloaded for satellites saving the GPS unit wasting time downloading it from the sats themselves at turn on.
It does seem that Navigon can not resume from the handover back to normal data as other apps can. The fact that it even says 'Destination reached' in a tunnel without A-GPS shows an inherent problem!
hello
I have a problem and hope someone could help me
I have TT7 on my HTC TyTN2 Kaiser, no problem
but gps works only if I put the phone on.
If I put off phone , wifi, BT, the program works but gps cannot fix any signal (gps is detected but do not fix signal)
Is there something to add or modify to have this working when I put off phone, wifi, BT (airplane mode)
thanks
nbnserge said:
hello
I have a problem and hope someone could help me
I have TT7 on my HTC TyTN2 Kaiser, no problem
but gps works only if I put the phone on.
If I put off phone , wifi, BT, the program works but gps cannot fix any signal (gps is detected but do not fix signal)
Is there something to add or modify to have this working when I put off phone, wifi, BT (airplane mode)
thanks
Click to expand...
Click to collapse
Workaround :
- enable phone from comm manager
- set a password for your phone
- launch the phone app, it twill ask for your password, don’t enter anything, just close the phone app
- launch TT and it should get the signal fix.
I know SGS has a lot of issue with GPS. Here's mine. I've cold start and standalone set-up in lbs test mode. Now the problem is it'll lock on to satellites in a matter of 20sec with 15m accuracy only when connected to wi-fi couldn't check for gprs since sgs doesn't save my apn =(. But with wi-fi switched off it doesn't speak to any satellites forget about getting a lock on them. Doubt here is, isn't standalone mode supposed to be GPS working without any data connection of any sort or am I missing something here? Kindly clarify. Also what does MS based and MS assisted mean in the test mode. Checked for GPS with Network Provider selected in test mode. I get accuracy of 3.8km here at my home....
Thanks & Regards
Bump to the top....
Sent from my GT-I9000 using XDA App
I just tested indoors (rainy here) and the SGS did get a lock. I've switched off cellular data and wifi, cleared the AGPS data with "GPS Status", and it took a long time (few minutes) to get a lock.
But that was indoors, where it always takes a bit longer to get a lock.
I tried it outside last evening and it would only see the sat's no lock =|
With data from network I can identify the location instantly. However, if I uncheck "Use wireless network", I have never located myself on Googles Maps. Is it a defect on the GPS?
Thanks in advance!
Google maps doesn't includes world map installed, it only store some caches.. you still need network to download map data & network based location, GPS is used for more accurate result & yes it's true p970 gps is not so good.
lesp4ul said:
Google maps doesn't includes world map installed, it only store some caches.. you still need network to download map data & network based location, GPS is used for more accurate result & yes it's true p970 gps is not so good.
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Click to collapse
Thanks for your help! In fact, I already have cache of Google Maps, then turn off the wireless connection, to figure out the performance of the GPS alone. It sucks!
BTW, I used HTC Touch before and its GPS could identify the location very quickly.
have you test with the GPS fix (in hidden menu) ?
Actually you are wrong, GPS in very good in OB.
I used it for a trip of 700 KM and it has difficulty only the first time when it aquires a position (this is normal if you don't use AGPS) like 3-4 minutes...
On the road I turned off GPS by simply locking the screen (IGO8), and on relaunch the GPS position will not take more than 30 seconds. I don't have any data on my contract so it was purely GPS!
The first time it's normal to take a very long time because a large number of sattelites have to be aquired to for pin-point accuracy. Afterword I think it works with 2-3 visible sattelites!
My previous phone was a HTC Diamond, and it was exactly the same if I dind't used the GPS app every day that downloaded sattelites in advance.
It works but it's slow (as it should be). For me it's around 1 minute in hidden menu. Best place for testing outside hidden menu is Compass app (If you don't have data connection for maps)
For hidden menu:
1. Go into the LG hidden menu (3845#*970#)
2. Go into GPS Test
Test it (you need activated GPS of course)
if it's really slow, try this (I think it's if you use network to pinpoint but everyone is suggesting it, so I will too)
1. Go into System Settings
2. SULP Setting -> SLP Server Setting
create new:
Nokia (slp address: supl.nokia.com, port: 7275, no cert and no TLS setting)
If it still doesn't work, try other variants (LGE SUPL, Spirent, etc).
Thanks everyone!
It works now! The. GPS is quite sensitive!
Sent from my LG-P970 using XDA App
In the gps test in the hidden menu, there's not such option as gps fix.
Me too, I'm interested in using my gps without the assistance of the network cells. I've already tried the three supl servers and it doesn't seems to work for me. So, if someone knows how to use it without network assistance I'll be really grateful.
Thanks in advance.
It should work out of the box.. afaik, you don't need to mess with the SLP servers unless you are using some sort of assisted GPS mode (with wifi or 3g connection). I'm using it straight out of the box (after installing the fresh firmware) and it works normal in the car (1-2 minutes first fix, a couple of seconds for any other subsequent fix). Getting a first fix while on foot does take a bit longer, but that's true with all the other non-android devices I've had. the OB has normal (no more, no less) sensitivity when it comes to GPS.
i think there it`s a problem in OB mine has problems with gps too , and already o try`d all kind of apps and even use the gps standalone from the fresh new update soft and nothing , fix the gps for the first time and after then i can`t travel with standalone gps