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Bluetooth GPS - Very Poor Performance!?

Is it just me/my hardware or is GPS over Bluetooth absolutely rubbish!?
I tried a Holux GR-230 unit first but had the usual problems in getting it connected. When I finally did, I was apalled by it's performance, usually failing to get a gps lock at all.
So I ditched it in favour of a Rikaline GPS-6031-X7. It picked up far mor signals and usually obtained a lock almost instantly. However, it's accuracy is very disappointing. Positional accuracy - it's usually ok on a motorway or dual carriageway but at slower speeds, it jumps all over the place, forwards, backwards, in the middle of fields hundreds of yards away - and that's the worst time for it to happen 'cos it's when you slow down for a junction that you actually need it. The second issue is directional accuracy - it often shows me driving sideways as it's so sloooooow to update/recalc the direction.
If this was my first experience of gps, I might be able to forgive it without a benchmark to judge it against. But I've used Navman with an iPaq, a LAM1 unit with my Nokia 9210 and a (cheap) CF device with my Dell Axim and they all performed far, far better! I know that TomTom Navigator 2 isn't the problem as it performed flawlessly on my Axim (PXA255).
So what's going wrong? Is it the bluetooth devices, or the bluetooth technology, or the XDA II? Will O2's bluetooth update improve matters?
I can no longer rely on this and I'm going to have to start taking map backups - something I've never had to do before and really defeats the object.
Any thoughts, experiences, comments, answers?????
Ged.

I think your problem could be the gps receiver.
I am using the Navman 4400 with my XDAII. It took some time and a couple of patches (from this site, thanks guys) to get it to bond via bluetooth, but now it's setup, it works great. It seems to be very accurate and tells me to exit roundabouts just at the correct time.
It's a bit slow to get the initial fix when first switched on (about 2 minutes) but once connected I have no problems.
Is the gps receiver positioned by a heated screen? If so, this will block the signal and produce the problems you describe.

Have you changed your car? Some newer cars have reflective windshields that can cause problems.
Cheers

Thanks guys. I know of both of the issues you describe but I drive a 3 year old clio 172 - no heated/reflective screen. The receiver usually sits on the dash and receives a very strong signal from upwards of 6 sats.
I've now emailed Rikaline too so we'll see what they come up with (if anything).

I am using the Holux GR-230 and it works flawlessly with towas latest patch 1.0.1.2, a very accurate gps based on my own observations with tomtom2.

Hi guys
I have recently received my new XDA II from Orange (know as SPV M1000)
I am using it with the Fortuna Clip On GPS, Tom Tom Navigator and a Jabra 250 headset.
So far I have had no problems with the GPS, it works every time. On a rare ocasion I have to reset the phone to get the head set to work but this is very rare.
Not sure if orange have modified the software but it all seems to work.

I'm beginning to think that it's the XDA that's at fault. I know TTN2 is ok, you guys aren't having any probs with bluetooth gps devices in general, and I'd have to be extremely unlucky to have TWO faulty gps receivers from different manufacturers!
Persuading O2 that it's faulty is another matter though.

i work in the in car navi business and a 3 year old cleo does have a metalic winscreen apart from the hatched area around the rear view mirror (for use with toll tags and other antennas).You will nead a re-radateing antenna mounted externally to get propper reception as the cleo also has a faradays cage effect making radio reception within the cab area very difficult.(they are a ***** to work on)

pinkslayer, shove it in somebody elses car, or slap it on the roof of yours and see how it go's in that location.

Should know my car a bit better really!
I had tried mounting the Holux in front of the rear view mirror but this didn't help so I didn't bother trying the Rikaline. And my wife has a clio too so no point trying it in hers.
So even though I'm locking on to 5-6 sats, it's still not sufficient!? Or is the metallic screen just causing additional latency?

Its not the number of sats, its the strength of the signal received, I have seen 8 sats showing but tomtom wont attempt a route until the signals are strong enough for a lock,

Rikaline GPS-6031-X7
hi all
i use a Rikaline -x7 with TomTom Navigator 2 on my xda ll with the bluetooth pach from
http://bluetooth.i-networx.de/index_e.html
and the update is slow when taking corners (ie the map is slow to turn to the heads up position) or if you come of a motorway/ dual carriageway thats not on the calulated route it will take some time to acknowledge this
but i do not have the problem of it at slower speeds it jumps all over the place
As for accuracy my old tomtom wired gps was better
but the Rikaline-x7 is usable

Thanks peops. I've now tried mounting it on the rear parcel shelf and also stuck it to the shaded area above the rvm but to no avail (even when it was back on the dash this morning, it took 11 minutes to get a fix and another 5 before it could calc direction - cloudy day!). As soon as it's dry enough, I'll mount it outside the car and see how it is.
I don't really want to do down the re-radateing antenna route as the whole point of having portable equipment is that you can use it anywhere and in any vehicle.

Im using the Rikaline GPS 6031-X7 and Im really happy with, no problems at all in fact I think its brilliant............

I'm using the fortuna clipon in a landy with heated windscreen. It doesn't seem to affect the signal (with or without the screen on) and I have to say i was expecting problems with it. It has been the only thing about the whole BT GPS/XDAII setup that I haven't had problems with..
Technology eh!

Does Pretec Compact GPS work with the XDAII BackPack?

Hi.
I already own a Pretec Compact Flash GPS unit from my days with a Toshiba E740 (another story!), has anybody tested this with the BackPack for XDAII?
If it works I will try and get a backpack, otherwise will get a new Bluetooth GPS unit. Prefer to get the backpack though, as it has other benifits.
Thanks
PBman

Good luck getting a backpack HTC doesn't seem much interested in supporting their old customers by making accessories.

I have one backpack and one wifi CF card with my Qtek2020 and all works fine. I think that the GPS CF card works fine too.

Well even if it works in the device I wonder how well a GPS unit will work with the aerial at the bottom... I am right in thinking that the compact flash unit is at the bottom of the backpack.
As for getting one, this is Moscow... if its been released you can normally find it, and if its not been released you will probably still find it
Perhaps I will go bluetooth GPS, and flogthe pretec off on Ebay...

i really doubt that connecting a grps in the buttom should matter much to the signal strength
i mean i can turn my phone upside down and speak just fine
or a HAMM radio antenna for that matter
it's much more about the length of the antenna then how high as in hand held human heigth you put it
if you want to know more search on google about dipol antenna math

But surely if the GPS unit is at the bottom some of the satellite signal will be blocked by the unit and your hands etc. also in a car the aerial would be down into the car and not up high in the windscreen.
Thought GPS needed pretty good line of sight.

not sure about gps
but in general those cm's difference in heigth from the ground should not be that different for radio waves
and your hand should not be able to block that much
i cant claim to know all that much about gps
but i would worry much more about the quality of the gps reciever then the location when the difference is not greater

It depends on the GPS. A lot of the newer ones, like the Bluetooth GPS's, can work through minor obstructions. I saw a review of the Socket Bluetooth GPS and it worked for the tester in his car's glove compartment.

a bit of help for a GPS question please

I've run a search on the forum but can't see anything that specific on this as far as guidance goes. dunno if this is gonna sound noobish but here goes.
GPS + tom tom.
would I be correct in saying that if you don't have a contract, ie you are on pay as you go, then GPS won't work cause data transmission needs to be part of the contract?
It's just, that up till now I always thought that being pay as you go I wouldn't be able to use GPS on my XDA unit.
however, I'm now wondering if I've got this wrong as a lot of the GPS units are bluetooth so I'm starting to wonder if I'm some kind of moron.
help advice etc appreciated to clear up my misunderstanding.

GPS use GPS satelites they dont have anything to do with the gsm network
you can use tomtom gps with pda's which are not phones
if you want

so as long as I have a gps receiver that is bluetooth compatible it won't use up any call credit etc and I will be using the likes of tom tom on the XDA 2s?
have I got that right? so I would pair the gps reciever to the phone and that would be about it.

gps dont use gsm ever no matter if you use it 24/7
and first swollow your sim card it dont mean anything unless you set tomtom or something up to get traffic or spycam stuff over gprs
you simply cant get gps from gsm they are 2 100% seperate things
gps is free and require it's own antenna you can use bluetooth ones
or you can use wired ones
it's all the same
p.s. your picture show you have a xda1 if that is the case then you dont have bluetooth and need to get the wired gps antenna look at tomtom's site which one is compatible with xda1

Tellan, sounds like u r confusing gps and gprs data. Gps is part of a sat nav setup(no cost for signal), while gprs is used to transfer data to and from ur xda(charged by how much data is transferred).
You may have found that u cannot access the internet on payg o2, this is not a fault on either the xda or the settings you may have. O2 dont allow it on payg in the UK! Though there are settings available that give u free access on payg, pm me if u want them.
Back to gps look on ebay uk and you will find a supplier selling the older style (leadtek 4951, I think) with all cables required for car fixing & xda charging for approx £40 delivered. Got myself one couple of months ago and it works great.
Word of caution dont bother with Tom Tom 5 go for TT3, 5 is full of bugs and can cause lots of problems. I had to resort to a hard reset to get things working properly.
Hope this helps, if u have any queries just ask again.

aaaah. that's were the confusion lies.
BTW I now have a XDA IIs coming and I will be selling my loyal XDA 1 shortly once I have everything transferred over.
right, so now I need a car kit and tom tom 3. what's a reasonable price to be paying for that stuff.
I'm asssuming with the car kit for the XDA IIs that I'm needing it to charge in the cradle as GPS munches battery power for breakfast.
BTW I'm going to get a 2400mah battery. from what I've seen on the web it's only a shade bigger at the back and will still fit the standard case.
any particular BT GPS recievers that are heartily recommeneded over the top of others.

If you get a wired gps it will charge the phone and gps, you will then just need a cheap mount. Look on ebay and you will get it cheaply. Just search on www.ebay.co.uk for "xda gps"

GPS receiver upgrade or to buy Tytn II

Dear All,
before to buy a Tytn II, I'd like to understand if the GPS comes upgraded by the future's ROMs (I think yes) or is necessary a future hardware change ???
P.S.:
I have a Tytn with the GPS Fortuna ClipOn BT, and I don't know is better to change the GPS receiver or buy the new one with GPS included.
Thanks a lot
Ciao ...

ritmia said:
Dear All,
before to buy a Tytn II, I'd like to understand if the GPS comes upgraded by the future's ROMs (I think yes) or is necessary a future hardware change ???
P.S.:
I have a Tytn with the GPS Fortuna ClipOn BT, and I don't know is better to change the GPS receiver or buy the new one with GPS included.
Thanks a lot
Ciao ...
Click to expand...
Click to collapse
Buy the new phone - its worth it. The GPS works fine & the phone has a lot more oomph (CPU memory etc)

Seconded, get the Kaiser and off load your BT gps. My Wizard is now relegated to my wifes car with my old BT gps and that is her SatNav solution. I am well happy just having the Kaiser as the gps works as well if not better, and I only have to carry one device around.

Had a bluetooth GPS unit connected to my AXIM as my GPS system before I bought this phone.
My AXIM crashed, battery died flat dead, so I had to use my phone as backup. Used the built-in GPS with TOMTOM on my Kaiser and it was AWESOME- worked perfectly!
Get this phone you won't need anything to supplement it what-so-ever...

No. The Kaiser built-in GPS chipset can't compare to BT-359 SIRF III. It sees less Satellite; also, many of them are invalid signal, that means these satellites were grey. With the ones are blue, the signal keeps going up and down. Sometimes, for somewhat reasons, Kaiser loose the GPS fix (you see the map turn around) even in the clear view sky, then you loose your current position.
If you're driving in the crowed sky area (e.g NYC), stick with bluetooth GPS SIRF III chipset receiver.
Read more here: http://forum.xda-developers.com/showthread.php?t=339257 I had used the BT-338 then upgraded to BT -359 which is slimmer, sleeker but lack of external antenna connector and less of batt. time life.

i have tomtom - works faster.
tilt gps - far worse. but it works at 95%.

ritmia said:
Dear All,
before to buy a Tytn II, I'd like to understand if the GPS comes upgraded by the future's ROMs (I think yes) or is necessary a future hardware change ???
P.S.:
I have a Tytn with the GPS Fortuna ClipOn BT, and I don't know is better to change the GPS receiver or buy the new one with GPS included.
Thanks a lot
Ciao ...
Click to expand...
Click to collapse
Frankly I doubt the inbuilt GPS is going to be as good as an external one. (I reserve my judgement till my Tytn II arrives. However, your decision should be based on expense too. Do you mind spending out the extra for inbuilt GPS by buying a whole new Smartphone?
If yes then no problem because you can still use an external gps. If you want to keep the cost down get an external one. I bought an i-blue 737. The device cost me 30UKP and it's never ceased to amaze me how good it is. This will pick up 7 satelites anywhere in my home regardless of where I am. No need to go near a window, the acuracy is astounding with WAAS + EGNOs enabled and 115000 baud coms.
As I say I doubt the inbuilt one is going to match this but it probably will be fairly decent.
Disclaimer: this is just my opinion.

Nghiem said:
No. The Kaiser built-in GPS chipset can't compare to BT-359 SIRF III. It sees less Satellite; also, many of them are invalid signal, that means these satellites were grey.
Click to expand...
Click to collapse
True for the reception quality, but not for the TTFF which is much shorter with the QualCOMM chipset than with a Sirf III (less than 5 seconds in most cases).
The degradation of the signal due to obstruction (when inside a car for example) is virtually identical to a Sirf III chipset.
The only real weakness with the QualCOMM chipset for the time being is that it has major problems getting a fix when moving quickly. I tried several times to get a fix while moving with ~450mph with a clear view to almost all satellites and the QualCOMM has a very hard time to find more than 2-3 useable satellites. Even after 5-10 minutes no useable position can be determined. Moving quickly to get a fix should not be a problem at all for any GPS chipset.
But I have high hopes that those "quirks" will get fixed with a future firmware update.

The Kaiser has an antenna port specifically for the GPS undeneath the battery cover. I don't know if a battery cover can be found that exposed it more gracefully but I imagine with a small antenna would augment the signal nicely.
That being said, without using an external antenna, I'm actually quite impressed with the accuracy. I wouldn't have anything to compare against it but it's always been dead on for me.
I use TomTom 6 but I've played with google maps and Windows Live Search.
I have noticed it can take a long time to get the first lock on occasion, and especially so when driving at speed. Not really a problem for me, as you usually plan where I'm going while the car is stopped.
-James

Since GPS works with as little as 3 sats, and 4 for 3D positioning, why does everyone worry about getting 7 tuned in? Seems a bit anal to me.
The Kaiser GPS IMHO is a tad slow to init, but other than that, it's worth every penny to not have 2 devices to handle at times. I've never had a problem loosing connectivity, so I'm 100% satisfied with the Kaiser. YMMV of course.
Now if HTC would use a decent CMOS sensor in the camera, then I'd call the phone perfect. But that's another thread...

Dear All,
thanks to everybody about the answers ... I think I'll upgrade my GPS receiver (is more cheap). In this moment, I wait other tests about the GPS of Tytn II.
Ciao, ...

scottwilkins said:
Since GPS works with as little as 3 sats, and 4 for 3D positioning, why does everyone worry about getting 7 tuned in?
Click to expand...
Click to collapse
Because the more satellites you are evaluating, the more precise the position gets and in case you lose track of one of the satellites, you will still be shown a valid position.
Adding to that, the RAIM functionality of GPS receivers for an even more precise position while getting rid of most common GPS erros only works with 5 satellites or more.
So, while it's true that you only need 3 satellites for an 2D position, this fix will not be very precise (due to lack of crosschecking with other satellites and typical GPS calculation errors which happen all the time) and you will lose your position as soon as one satellite disappears from your view.
However GPS receivers which can track more than 12 satellites at any given times are useless because there will never more than 12 satellites visible at any specific point of the earth, most of time you can only track and use a maximum of 8 satellites simultaneously.

vacsed said:
I tried several times to get a fix while moving with ~450mph with a clear view to almost all satellites and the QualCOMM has a very hard time to find more than 2-3 useable satellites.
Click to expand...
Click to collapse
Doesn't your F15 eagle have built in sat nav?

GPS Receivers

Hey guys,
So I finally got TomTom software and SA maps ported onto my HTC. Now I wanna know, Its kinda retarded to buy a GPS when my phone has all the functionality, just cant search for satellites. Would I be able to buy a normal GPS receiver and use that to grab the GPS satellites, pair it with my phone and use the maps that I have installed on my phone
Thanks

Unless your phone has a GPS chip, your best solution is a bluetooth GPS puck.
They go for anywhere from $30-60 US.

Im_Gumby said:
Unless your phone has a GPS chip, your best solution is a bluetooth GPS puck.
They go for anywhere from $30-60 US.
Click to expand...
Click to collapse
Thats what I wanna get the receiver for though. Surely that would have the chip... all im doing with my phone is running the software, which enables me to pair the device via Bluetooth
Getting a GPS is a bit pricey for me, they start retailing at about R2000 here in SA

I bought a second hand Royaltek 2100 for about 25 dollars and I absolutely love it....I als had an other PNA GPS with the same chip, same channels but compared to the RBT 2100 it's a pain. It takes 4-5 minutes on cold fix for satellites while the RBT 2100 takes about 20 seconds..

Just ordered a GPS receiver, lets see if its any good and if it works with TomTom software....
Thanks for the help guys