Isn't it small

[kezz]

Just got my Gilsson MCX Amplified Antenna

From the USA in 3 Days.

In a very thin envelope.

I really didn't think they had sent me what I wanted until I opened it.

I thought it would be bigger, Dunno why.

Ya can tell I've never had one before.

So off I went to the back garden to try it out, first without then with.

What a difference.

Hopfuly now. Next time in London I don't get lost.

We'll see.

I'll tell you. Nothing worse than geting half mile ish to your destination. Then at Leicester Square bam. Nothing!!

AArrrgghhhhhh!!!!!!

Have you ever driven there at 7.30 at night. Never seen so many people in my life and NO IQ, damn buildings.

So has anyone with and external antenna been down there?

Did you still have a connection?

Cheers

kezz

[jonasolof]

Welcome to the world of Urban canyons, multipath reflexes and intermittent loss of signals.

Downtown, you need the optimal antenna placement, i.e on the roof.

With many people around, driving is slow. The iQue can go for a short time living on the memory of sats it just saw. But if if you drive slow (as in London with all these people around), it can loose track. Other antennas don't work better. You've hit the limit for what a consumer grade GPS receiver can do.

Remedies:

Garmin 2650 with dead reckoning linked to speedometer and inertial sensoring.

Wait for Assisted GPS which supports the GPS receiver with sat ephemeris data over the cellullar network. The European Galileo system will more than double the number of sats in the sky, increasing the chance that there are some in view from the bottom of the canyon.

Accept fact of life. The combo will work well in most difficult environments but not all.


In the BT GPS 10, one can set the time that the GPS receiver relies on old data but this option does not exist in the iQue 3600.

Also, it should be mentioned that Lock on road actually can make positioning worse under certain circumstances, such as in urban canyons.

[kezz]

Thanks for the reply.

So what your saying is, I'm still going to get lost even with my nifty little antenna on the roof of mi van :(

Awww, that's no fair.

[marksmac]

Originally posted by kezz
Thanks for the reply.

So what your saying is, I'm still going to get lost even with my nifty little antenna on the roof of mi van :(

Awww, that's no fair.


You know what's funny - me and GPS feel the same way about driving in crowded cities with very tall buildings, we don't like it.
We (me and GPSs) both prefer to drive/shop/travel where there are trees and open roads and plentiful free parking and you can see the sky...

[Bokkie]

Originally posted by kezz
Thanks for the reply.

So what your saying is, I'm still going to get lost even with my nifty little antenna on the roof of mi van :(

Awww, that's no fair.

Some ba$tard will nick the antenna off your roof, London being London. They'd even nick the snot from your nose on a cold winters day if they thought they could get something for it.:D

[apersson850]

Getting ephemeris data from some other source is good, if you can't get a lock in the first place. Just remember that if we assume you found some more open spot, where the ephemeris data could be received, then you are in the same situation as if you got that data via GSM, GPRS or found it under a turd. probably a polished one, if it's hiding such things.

[kezz]

Just thought

If you did loose signel, you could simulate routing to get you to the final bit.

Hard I know but it could be done.

What about GPRS

Is there any products out there that use it. I know phones do, but what about a proper sat nav

Thanks

Kezz

[jonasolof]

Ephemeris data over the cell work is coming in 3G/UMTS in Europe. It's part of services for the 3G network. It won't come over GPRS AFAIK. Exactly how it is going to work isn't known yet, there are many possible variations, in part depending upon how greedy the operators are. It'll probably be a subscribed service, although it wouldn' need to be, since ephemeris data doesn't have to be directed at an individual phone. The 3G cells being small, data would be relevant to all phones within coverage including approximate initial position.

Since emergency calls should be possible to be done without contact with your operator, it is posible that GPS support will be cost free, but I doubt it very much.

The problem you describe in London City is the same as what you encounter when you pick up a rental car at a busy airport. Surrounding buildings are high. You can't get a signal until you've driven out in the open - but you can't drive out because you don't know where to go.

Place your iQue with the antenna totally folded out against the roof of anybody elses car outdoors. When you've got a good fix, quickly move to your own car without closing the antenna. Once in your car, attach external antenna and after that close the internal antenna.

Down town survival:

It's always much easier to get a fix if you stand still. So if you see you start to get a good signal in a street corner while waiting at a red light, remain there until you got a fix. Don't bother about people blowing their horns behind you. Just pretend you can't start the car. Then, when you've got a fix, go.

To fake the problem, it might help to put in a relay that cut's power to the ignition even when you crank the start motor.

[JMckie]

Originally posted by jonasolof


It's always much easier to get a fix if you stand still. So if you see you start to get a good signal in a street corner while waiting at a red light, remain there until you got a fix. Don't bother about people blowing their horns behind you. Just pretend you can't start the car. Then, when you've got a fix, go.

To fake the problem, it might help to put in a relay that cut's power to the ignition even when you crank the start motor.

Good suggestion, but I would like to add to this. Stopping at a street corner, the sky is still partially blocked by buildings on either side of you. You can see more satellites by stopping right in the middle of the intersection.

While waiting for fix: turn on your blinkers. Make sure the other drivers see you wringing your hands in frustration. Use your cell phone and pretend to call an auto service.

[apersson850]

What do you mean by simulate? Guess the speed, and try to simulate in real time?
Or just show the route on the map, so that you can read it, like you would on a paper map?

[jonasolof]

Originally posted by JMckie
Good suggestion, but I would like to add to this. Stopping at a street corner, the sky is still partially blocked by buildings on either side of you. You can see more satellites by stopping right in the middle of the intersection.

While waiting for fix: turn on your blinkers. Make sure the other drivers see you wringing your hands in frustration. Use your cell phone and pretend to call an auto service.

You could also add what I saw last winter. Three men were kindly helping a woman to drive away from an icy parking lot. Looking at them from some distance, I saw that the rear wheels didn't move although they pushed the car forward. So I went up, had a look and asked - what about the hand brake? She was blond, albeit not so young, so she was excused by them all.

This scenario evolves into a Mr. Bean plot. Imagine him with his newly bought iQue, internal antenna only, starting out from his quaint little farm in Cotswold humming and singing to deliver fresh eggs to the Savoy in London. Everything goes well (unrealistic) until he enters London City. Then he looses his satellite reception in the intersection of Oxford and Regent streets...

When cell phones were new in Sweden, about 1988, there was a story about a business man who had just got a call from the US. Anxious to settle a deal he stopped in front of a major tunnel entrance, since he was well aware that there wasn't any cell phone connection within the tunnel. And there he stood, negotiating, for twenty minutes at the bottle neck of Stockholm.

It led to the rapid installation of leaking cables in the tunnels so that people wouldn't cause a traffic hazad.

[apersson850]

How about simply unfolding an ordinary paper map?
It gives the double benefit of both giving the GPS some time to get signals as well as maybe making you somewhat wiser regarding the actual problem at hand, i.e. to find your way around the city.

[kezz]

Hi Again

apersson850

Yes, I do mean when you put in a rout but not have the atenna opened the iq asks if you want to simulate the route.

So if you do loose signal you could do a rout from where you are to where you are going, Not a long distance.

It would give you a good idea of where you going.

Also, maps what are they.

Ogg them things I threw out when I spent an Arm and a Leg on this thing that doesn't like tall buildings so you spend your other arm on an external antenna only to be told that it's not much better.

I'll just not take jobs in City Centre.

Ohhh Boo Hoo, Ohhh Whooo

[apersson850]

Yes, but you already have that route, since you calculated it to your destination in the first place. The only thing that happens is that the moving map function is lost. You have to pan the map yourself.

So when you loose the signal, this is already done.
Then it's worse if the iQue repeatedly recalculates your route, either because you are no longer on the route, or because it thinks you are off, due to signal loss. The relatively small heap in these Palm devices means that the iQue uses the oversized graphics buffer for route recalculation. That's why the map goes blank, when it has to recalculate twice in succession.

At that moment, it's not worth anything for guidance, not even by manual means.

[fards]

I've been playing around with my 3G phone for some time now.

On orangeworld it has a locator function with mapping built in, I think it's called "where I am now".

Sometimes it's pretty good, sometimes it's pretty crap, much like 3G itself really.

It doesn't work on 2.5G (GPRS) setting at all, so it sounds like the Ephemeris data
jonasolof mentioned. The service is free but obviously the data transfer of the WAp site isn't, but then I've got 50meg of that a month for 12 months for free!

[jonasolof]

That locator could simply be based upon the cellular network knowing in which cell you are, or possibly triangulating between several cells. For that the phone doesn't need any built in GPS.