yashsingh1/xdaforums huggingface dataset:
[Touch HD General] Jogiya:
Review from SlashGear

HTC Touch HD's review by SlashGear talks about the GPS lag..

this is the part about GPS performance of the Device:

"The HTC Touch Diamond has been criticised for its GPS performance, which can lag behind actual position when moving at speed. Hopes were high for the Touch HD to avoid such a fate, but unfortunately that doesn’t appear to be the case. Whether from the processor (the same 528MHz Qualcomm MSM7201A as in the Diamond) or the GPS receiver itself, when driving the indicated position is always 50-80ft behind. This makes navigating via the on-screen directions incredibly difficult. At lower speeds, such as when walking, the Touch HD has no problems, just like the Diamond. We’re still attempting to get hold of some alternative GPS programs, such as TomTom or Garmin Mobile XT, and will update this review when we’ve had an opportunity to try them out."

has anyone else bought the Touch HD yet who can confirm this?

i just hope the GPS lag isn't as bad as the HTC Touch Diamond/Touch Pro as i'm going to order one pretty soon.
[Touch HD General] iznee:
For the sake of millions of readers and potential touch HD buyers like me,can someone who already own a touch HD,please be kind enough,do an experiment about this gps lag issue and give an absolute answer to this issue.Gps lag is very noticeble when you are navigating at high speed(eg:80-100km/h) or when doing multiple rapid turns(eg:driving on back alleys).at low speed(slow drive or walking),no lag is apparent.Currently i'm using ipaq 612c where it has this lag issue and its most noticeble when using Garmin XT.When using mapking or tom tom it is not that bad..Really waiting for all your answers.

Thanks in advance for all your help
[Touch HD General] david-v:
Ok, I have performed an experiment. Hopefully it will help you and "millions" of readers to decide if GPS lag is a problem or not on this device.

Test setup:

PDA 1: Mitac Mio A701, GPS chip: SIRF III, navigation software: IGO8

PDA 2: HTC Touch HD, GPS chip: Qualcomm, navigation software: IGO8

Experiment:

I start IGO8 on both devices and select the same destination. They both pick up GPS signal and the show starts..

Result:

PDA 1: depending on your speed, there is a GPS lag. This is between 0-2 seconds. In distance I would say about 20 to 50 meters. Again, all depending on your speed. When you stop (which unfortunatelly happens a lot in the netherlands due to high traffic :mad:) the GPS gives the right position.

PDA 2: see PDA 1. There is practically no difference. Sometimes PDA 1 is more ahead, sometimes PDA 2 wins. The voice commands start virtually at the same time "take a turn left", "leave the highway" and so on. Maybe PDA 2 is a bit faster (less GPS lag) since I heard the voice like a 10th of a second earlier than on PDA 1.

Conclusion:

GPS lag is a problem that practically all "cheap" GPS devices have, specially in a moving vehicle. Since your GPS data is refreshed every second, you would be one second off every time. Moving at 100km/h, that means an offset of 27 meters. Moving at 150km/h that is about 41 meters (and yes, I know I should not drive that fast in the netherlands :rolleyes:). Add to that the GPS errors and you will get an impression on how hard it can be to predict where you will be in a second.

You could then say that the navigational software should take that into account and predict where it would be, but that also has a negative side. Have you noticed what happens when you do not follow the course laid ahead by the navigational software? it stays on course for a couple of seconds and then it notices you actually turned left or right, thus the direction should change.

The more aggresive the prediction is, the more you will have a problem when deviating. The less prediction, the more GPS lag you will have.

Is this a problem while driving? I have never considered it a problem. On the highway you do not decide to take a turn within 50 meters (I hope :)). In the city, you should have way less problems with GPS lag...

Last, for all the "millions" of readers, please read these two articles:

Article 1, an abstract about navigational state estimator

Article 2, a forum discussing this very problem in the i-Blue receiver. Pay special attention to the answers given by JakeRich

I hope this helps you all out...
[Touch HD General] Beards:
David,

I am so very pleased you had these two devices with the software mentioned.

It just so happens that I too have a Mio A701 with iGo and my next purchase will be the Touch HD.

Your test served as a good starting block for me to build upon.

I did wonder how well the Touch HD would fare against my A701.

Many thanks.

Beards :)
[Touch HD General] gergy:
Thanks for your test. What about TMC info with iGo8 ?
[Touch HD General] david-v:
The device finds the TMC receiver (using 8.0.x version, 8.3.x version does not find anything) but then it does not find a channel. This would need a TMC expert to work out...maybe you need to change something in the sys.txt file of IGO8
[Touch HD General] JTHM:
Something I would add is that until last week I was using a SirfStarIII equipped BT GPS receiver linked to my Hermes and running TTN 6.03, now I'm using the Touch HD internal GPS and TTN 7.45. I have found that the GPS signal appears to be significantly weaker on the Touch TD. However, it does have the capability to pick up more satellites it seems.

In my standard journey between home and work the BT GPS receiver never picked up more than 8 satellites but never picked up less than 4 and spent most time tracking 5-6. The Touch HD at times picks up 10, maybe even 11(!), satellites but often drops to 2 and spends most time tracking 3-5.
[Touch HD General] BerreZ:
Impression

I'm using Tomtom 7,451 now on my HD.

I tried it with the internal GPs and even with an external bleutoth GPS receiver from Tomtom itself.

The so called lag is the same in both cases.It is caused by the slow refreshing rate ( almost 1 second ).That is not a major problem and is the same that I experienced already with the Polaris,Cruise and Diamond.

So when driving try to think at least 1 second ahead.

When you're not moving I got a pefect lock on my position with Tomtom but with Googlemaps i'm of by almost 150 meter to the East.

So that's software I think.
[Touch HD General] utvol06:
I get my touch hd today. looks like I wont be installing Google maps at all on it. I'm going to buy Co-Pilot 7 when I get the chance. I also like Windows Live search GPS app, but it may lag like google.
[Touch HD General] david-v:
Google maps is already preinstalled, at least on my Touch HD it was (Netherlands)
[Touch HD General] pzucchel:
last word on gpslag?

Hi to All,

Personally, i start realizing the limitation of forums in producing real information.

First of all, most "commercial" and consumer GPS update their position every second, as correctly pointed out in this forum. Said this, faster position updates are possible for professional devices, see

http://www.dsprelated.com/showmessage/22833/1.php

but we can probably forget about it for the time being.

so, don't be surprised if - driving at 100 km per hour alias 30 m/s - you will miss the exit by 30 meters. Be reassured: Felipe Massa will miss the box by 100m if he would drive by looking to the GPS - and your braking distance was anyway 60 m....aaaghh....i hope i will never meet any of you while making the test.

My firm and conclusive opinion after extensive evaluation with Igo and Tomtom and gwatch:

The GPS LAG on the touch HD is a metropolitan legend invented by i-members!

:eek::eek::eek::eek:

If you check on igo8, there is a small dot representing the actual position, and the arrow or the car is the position compute by software interpolation/filtering etc. Everybody can notice that the dot moves instantaneously. It is a matter of software to decide how to filter this data, and how "reactive" you want the position change to happen. On top of this, it is obvious that updating a VGA or WVGA screen will be heavier than updating a small screen, so there should be a lag which is dependent on the navigation software you use and on the load on your telephone.

However, there is definitely no lag on tomtom....the problem is: how to buy version 7?
[Touch HD General] hrcro:
Here is video comparison omnia vs hd

It seems to me there is little lag on hd.

Colud somebody translate it?

http://www.youtube.com/watch?v=v45--rkRgjk
[Touch HD General] utvol06:
I got my Touch HD today and after running GPS test I can say it has much better GPS reception and performance than my Touch Pro. I believe the issue is software compatability with the GPS chipset. Google maps is the main program that lags. TomTom7, Co-pilot 7, IGo8 don't have lag issues.
[Touch HD General] speed200:
Can you share with us the medium fix time of the HD?

Do you believe that TP will have some kind of fix to this issue like HD seems to have?
[Touch HD General] david-v:
medium fix time? in my case it usually gets a fix when I click on the map in IGO8, even before I start searching for an address. For me the fix is instant. I would say between 2 and 7 seconds after starting up IGO8.
[Touch HD General] utvol06:
My HD gets a much quicker fix than my Touch pro or my Kaiser. like 15-20seconds max cold and 3seconds hot.

I'm waiting to get a good GPS program to do lag testing as google maps has software issues with the Touch HD and Diamond/Raphael.

I'm planning on getting Garmin Xt or Co-pilot 7.
[Touch HD General] peek:
I can only quote your post!

Everything's perfect here on TomTom7 driving in normal roads at 50 or 80 km/h.

Have fun with your HD ;)
[Touch HD General] wfhowell:
NO lag

I have tt 7.91 on my HD and it looks marvellouuuuus. I have no lag that I can tell. So far i love my HD.
[Touch HD General] Philio25:
I've not used the GPS much on the Touch, but have tested it briefly, it's a million times bettern than my TyTN II!

It finds my position in seconds instead of minutes and finds more satellites generally as well.

I've noticed with both that Google Maps is always slightly off, but then TomTom 'locks' you onto the nearest road usually anyway.

Can someone tell me where I can get TomTom 7? They only have version 6 on their website!! (PM me plz if shop links are not allowed on here).
[Touch HD General] BANE:
Greetings.

I might be a little off topic here, but I hope you can indulge me. With onboard GPS, i'm assuming all you need is a 3G internet connection to position??

If so, how data intensive is it to run? I understand that when using google maps mobile, you are warned that it is a data intensive program and is suited to an unlimited data plan.

Vodafone 'unlimited' is actually limited to 500MB data a month. I'm not planning on using GPS in my car for extended periods every day, but would like to explore and play with it without killing my data allowence.

Thanks.
[Touch HD General] eaglesteve:
Nobody in the right mind would use googlemap, which uses up the data quota and doesn't even count as a proper navigational tool. You do not need data connection when using a proper GPS application. Having said that, TomTom does have some additional optional features for users to be warned of moveable police camera for example, and such features do access a server for information.

Back to the topic. One must understand that many factors are involved in GPS's positional accuracy. For example, if you're surrounded by high buildings, the signal echo and reflection sometimes make certain navigational software think that you're at a neighbouring street. Such problems are addressed by software correction, and many good software on winmo do address it. Also, signals comes in from the satellites in regular intervals. When cars travel in high speed, some gps software show your car position based on the last received signal. This is a limitation of the software, not Touch HD. A cleverer software,such as IGO, would extrapolate the most likely position based on your current speed and last received position, so it can show your car moving even inside a tunnel, where there is no GPS signal.

Hope this puts to rest the issue of GPS lag,because there isn't.
[Touch HD General] Philio25:
You need to connect to the net to use Google Maps as it downloads all the maps as you go (I think it caches what it downloads though???).

Google Maps is great for walking around, but I wouldn't use it in your car, sure you can plot routes but looking at a birds eye view over something like TomTom giving you directions is a BIG difference!!

You don't need an active data connection for TomTom etc.
[Touch HD General] speed200:
I´m happy to hear this because I´m going to sell mt TP and buy the HD.

My only sorrow is losing the keyboard...:(
[Touch HD General] CCN0301:
Hi Iznee/all it may concern

I have just purchased the Touch HD, having previously owned a Touch Cruise.

I'm afraid to report that having loaded TomTom 7, I noticed a quite considerable lag time on my new Touch HD. I also checked my HD against Google Maps and experienced the same lag issues. I have to say that I never experienced this with my old Touch Cruise, which was simply fantastic as GPS device with TomTom.

Sorry I am not able to deliver more positive news...hopefully HTC will have a ROM update/fix soon.

Regards

CCN0301
[Touch HD General] Da_Kem:
If you are looking for a free navigation program take a look at nav4all. Free and very good... I use it on my HD and BB Bold.
[Touch HD General] onesolo:
I had the TP and I felt/feel that the new soft keyboards wont stay behind from a hardware keyb.
[Touch HD General] Beards:
When you say it is free there is a small cost yes in going online with your phone to talk with the Nav4All server which then uploads the info you have requested to your phone.

Have you worked out just how much these costs are and how often you need to re-contact the server?

Beards
[Touch HD General] speed200:
Are you sure about it?

It´s only you that have noticed that....
[Touch HD General] speed200:
Espero que sim.

I really hope so.
[Touch HD General] utvol06:
I had the TOuch Pro and now just got my Touch HD yesterday. I can say I'm in-love with HTC again. First thing you will notice is the huge iphone-ish beautiful screen. :D

2nd thing you'll notice is that the virtual keyboard has a larger area to work with than the Touch Pro...less mistakes. I could barely use the virtual keyboard on my touch pro. On the HD i rarely make a mistake.

3rd thing you will notice is how much better the GPS reception is over the TP. With the TP getting a fix took a while, and when you did get a fix and started using something like google maps the location triangle would lag bad and veer off the road every so many seconds. With the Touch HD you get a COLD start fix in 15 seconds flat, a HOT start in 3 seconds...no joke.

I used Windows Live Search Maps testing the GPS, which is similar to google maps, but has better guidance. my position stayed on the roads the whole time and when I made a turn it followed my vehicle exactly and did not run off the road.

Now lets get to the lag. I tested the Kaiser(AT&T Tilt) and the HD back to back using live search gps maps and notice no difference in lag. both did have a little lag, but even better units have some lag. I would say the Kaisers lag when say crossing an intersection while watching the triangle get to the same spot was 1-1.5 second delay. THe Touch HD was 1-2seconds delay depending on speed, but the HD was never more than 2seconds behind at higher speeds 70mph etc.

Both very acceptable IMO. As I've watched even a 500 dollar dash mounted Garming lag 1.5-2 seconds when passing a road on the screen.

Now I plan on getting Co-Pilot 7 live or Garmin Mobile XT. From what I hear those programs like TomTom and IGo8 have even less lag.

You wont regret moving to the Touch HD.:cool:
[Touch HD General] speed200:
I really hope so because I´m going to buy it this Friday at Expansys.
[Touch HD General] Bodisson:
Just to clear something out: Nothing is perfect, even GPS!

And some facts:

Summary of GPS Error Sources

Typical Error in Meters.....Standard GPS....Differential GPS

(per satellites)

Satellite Clocks.........................1,5..............0,0

Orbit Errors..............................2,5..............0,0

Ionosphere..............................5,0..............0,4

Troposphere.............................0,5.............0,2

Receiver Noise..........................0,3..............0,3

Multipath.................................0,6..............0,6

So for standard GPS we come to max error of 10,4 m

Source: Trimble (How GPS works?)

There are also other calculations of total error out there, with error range from 5 to 15 m. So do not expect pinpoint position!
[Touch HD General] utvol06:
Great point...I Didn't know this.
[Touch HD General] Bodisson:
Yeah. And we're lucky U.S. government cancelled nasty thing called "Selective Availability".

The idea behind it was to make sure that no hostile force or terrorist group can use GPS to make accurate weapons.

Note to all: Link in previous post changed to point to correct, GPS-related pages.
[Touch HD General] speed200:
Just take a look of some tests with TP:(

Comments?
[Touch HD General] syqe:
and thanks to ur post i decided, gonna buy one next week, thanks for the feedback!
[Touch HD General] Guus_:
No GPS lag

I tested the GPS with TomTom 7.450, 4 times now, 4 different routes, all perfect, no lag at all, and a very fast fix. Even when I was looking for lag :) (because of this thread I was watching the screen/road carefully), I didn't see lag at all. The video performance, that's the real problem of this device.
[Touch HD General] Mark One:
Any noticeable issues with the TT display due to video performance? On my Polaris the screen rewrites were quite obvious for this reason.
[Touch HD General] utvol06:
great to hear...You wont be dissapointed.
[Touch HD General] Guus_:
No TomTom's video performance is good, i meant that the only serious problem with the device is: no proper video playback support(DivX/Xvid). The GPS-lag is a rumour, i don't know where it came from, but there is simply no lag. Just tested it again lol.
[Touch HD General] Magicdead:
ok i tried this today with my HD and the touch diamond of a friend. we both used tomtom 7.450, cold start except running QuickGPS.exe in advance to get some satellite info.

Both phones were side by side.

It took my hd about 10-20 seconds to get 5 satellites (the diamond had none at this time). After 40-50 seconds, the diamond had 5 satellites too (it never used/got more than that), whereas the HD used 8-9 at that time.

Now the test track was 500m on foot, running at about 10km/h. The HD updated the position fluently, there was no lag (ok sure, not surprising at such low speeds) and the position was always correct. Whereas the Diamond didn't even update the position once (it got the initial position right, but maybe 500m was too small a difference).

Ok, i admit, it's not the best test (maybe something was wrong with his diamond), but still, the HD worked like a charm, especially in comparison.

Also i never had any lag when driving, so yeah, GPS Lag on the Touch HD is a myth.

Have you tried TCPMP? It plays XVID encoded avis very well, except for the occasional lag in the video. Though the lag is most probably due to bad video encoding, as the same video lags in VLC on my desktop pc as well.

The standard TCPMP doesn't work on the HD though, you have to get the one from the wiki at http://www.4shared.com/file/51243023/beaf1cb8/TCPMP-072RC1-ARM-PPC-recomp-03CAB.html.

Hope that helps
[Touch HD General] Imperium:
TomTom playback performance is quite disappointing though it's like a slideshow on my HD :(
[Touch HD General] pzucchel:
i strongly disagree/agree depending on your interpretation of errors: those you mention are obviously ABSOLUTE errors! if you move by two meters, your GPS will definitely see a difference since the ionosphere doesn't change/move...

Navigon 7 reports the HDOP (Horizontal DOP) to be down to 1 depending on the number of satellites.

What is DOP?

http://en.wikipedia.org/wiki/Dilution_of_precision_(GPS)

http://users.erols.com/dlwilson/gpshdop.htm
[Touch HD General] pzucchel:
A Physics Reminder

Apologies to everybody, if i start "shouting" but i don't know how to make clear the following statement :) - I challenge anybody in disagreeing:

a (consumer) GPS provides you with a position fix every second. If you travel at X km/h, you travel at x/3.6 m/s. Since your GPS fix can be as old as one second - a lag of x/3.6 meters is TOTALLY normal and expected for EVERY (consumer) GPS!!!

Example: car speed=72km/h --> speed=20 m/s --> spatial lag UP TO 20 meters

Said this, keep being afraid of ghosts: with Navigon 7 the touch HD works better than my 2000 Euros GPSMAP296 - an aeronautical GPS: it fixes faster (5 seconds or so), it has equivalent DOP, and exactly the same lag of the TomTom One as i tested for 20 minutes by listening to the voices in perfect sync!

...I don't work for HTC and i don't need to advertise for the best PDA ever built!
[Touch HD General] arfster:
No real lag on mine with Tomtom - it's maybe a second behind real position, when travelling at 30-40mph (48-64kph). Barely noticeable.
[Touch HD General] PtitRun:
Hi !

I'm using igo 2008 8.3 on my HD and i've got a lag (up to 50/100 meters).

really looking forward to fix that :(
[Touch HD General] Eclogue:
Some more feedback -

I've got an Dell X50v (640x480 WM PDA) with external GPS and an HD.

Using TomTom on both at the same time, the HD is slightly behind (perhaps 10 metres at 40mph), and has a noticably lower fps.

Both are perfectly acceptable however. My guess is that the difference is mainly down to the difference in fps in my case, but that's just a guess.

Edit:

this looks interesting - maybe it's the polling interval?

http://xdaforums.com/showthread.php?t=460753

I suppose the most important point is that I'm not going to use the X50v any more, I'm happy that the HD is 'good enough'.
[Touch HD General] Felipe Rodriguez:
HTC GPS Lag

Hi,

I have tested my HTC Touch HD and it lags, certainly, the math above is good, but only verifies the fact that something, either GPS chip itself or the infamous "intermediate driver" is buffering position reads by 1 second at least, I mean that every time tomtom (or any other navigation software) reads the GPS, the system returns the position the device had one second ago instead of the position the device has exactly at the moment of the reading...

Even if you polled the GPS every 10 seconds, the position should be updated correctly that is, the software should show the position the device has at the very same moment of reading, not the one it had 10 secs. ago!, the only difference is that you would see bigger increments in position but always accurate every time the system updates it.

I compared this with my "old" T830 PDA which has a SiRF III Star GPS (no QuickGPS) and needless to say, the position is accurate to approx. 5 meters no matter the vehicle speed and using the same version of TOMTOM in both devices.. :)

BTW, on the T830 I have setup TOMTOM to read directly from hardware COM port (disabled "GPS automatic managing"), if I disable "automatic GPS management" on the Touch HD, the COM ports disappear and I can't connect, maybe because GPSONE chip doesn't implement true serial port interface but it's emulated by the driver.
[Touch HD General] michael_r:
Would it make sence to use a BT external receiver while in a car, and only use internal while walking? I assume a $40 BT receiver is still more powful then the internal one, and lag while walking is unimportant.

Thanks