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| Author |
gps mobile tracking
|
|
| Shannon 2007-02-15, 10:33 pm |
| Has anyone heard of cingular having any intentions to offer
this service? nextel and verizon both offer this service.
it sure would be nice to be able to track the kids whereabouts
at any given time.
| |
|
| In article < 0JOdndS5m5b3kkjYnZ2d
nUVZ_uqvnZ2d@comcast
.com>,
"Shannon" <shania_2_yu@yahoo.com> wrote:
> Has anyone heard of cingular having any intentions to offer
> this service? nextel and verizon both offer this service.
> it sure would be nice to be able to track the kids whereabouts
> at any given time.
I'd plant chips in them.
--
To reply by email, remove the word "space"
| |
|
| Shannon wrote:
> Has anyone heard of cingular having any intentions to offer
> this service? nextel and verizon both offer this service.
> it sure would be nice to be able to track the kids whereabouts
> at any given time.
Cingular is unable to do this with the positioning technology that they
use. Sprint and Verizon can do this.
Some European GSM carriers are deploying technology that allows this,
but I doubt if Cingular intends to deploy it any time soon. They have
their hands full now with their HSDPA deployment.
My wife's company just switched to Verizon, and one reason was that they
wanted the tracking capability. They used to be on Nextel, but the
coverage wasn't good, as they routinely go to very rural parts of the
county, so they needed AMPS and CDMA.
| |
| Thurman 2007-02-15, 10:33 pm |
|
"Shannon" <shania_2_yu@yahoo.com> wrote in message
news:0JOdndS5m5b3kkj
YnZ2dnUVZ_uqvnZ2d@co
mcast.com...
> Has anyone heard of cingular having any intentions to offer
> this service? nextel and verizon both offer this service.
> it sure would be nice to be able to track the kids whereabouts
> at any given time.
For the present, Cingular depends on an external GPS except for HP PDAs.
Just this week, more cell phones have been announced by the manufacturers
that have a GPS chip installed, but have not been through the service
providers configuration.
I suggested my daughter look at the Walt Disney cell phones that do not look
like a Mickey Mouse phone. Disney has done some interesting 'usage fencing
re max minutes, whom can be called, location, etc. My only mistake was
mentioning it front of my granddaughters.
| |
|
| Thurman wrote:
> For the present, Cingular depends on an external GPS except for HP PDAs.
> Just this week, more cell phones have been announced by the manufacturers
> that have a GPS chip installed, but have not been through the service
> providers configuration.
Cingular and T-Mobile use a less accurate positioning system, called
TDOA, which is accurate to about 350 feet (at least 95% of the time).
The Verizon GPS system is at least twice as accurate (about 150 feet)
and in most cases is accurate to 50 feet or better.
I think we'll see a lot more GPS capable handsets as European carriers
are adding GPS capability to their systems, but unless Cingular deploys
a way to use the GPS capability in new handsets it won't matter, as
there will be no way to do tracking.
| |
| Thurman 2007-02-16, 10:33 am |
|
"SMS" <scharf.steven@geemail.com> wrote in message
news:45d539b4$0$2719
5$742ec2ed@news.sonic.net...
> Thurman wrote:
>
>
> Cingular and T-Mobile use a less accurate positioning system, called TDOA,
> which is accurate to about 350 feet (at least 95% of the time). The
> Verizon GPS system is at least twice as accurate (about 150 feet) and in
> most cases is accurate to 50 feet or better.
>
I upgraded to a 8525 in November to be used with a Holux GPSlim236. They
offered Telenav free for the first 6 weeks. Since I owned Microsoft Streets
and Trips and DeLorme's Street Atlas, I tried it. It's a nice service but
the 'yellow page' directory is limited. My best guess for accuracy was ~12
feet parked, ~50 feet at 30mph, 100 feet at 70mph. I suspicion Telenav uses
your queries to update their database from the address you enter. That's an
inexpensive way to build a directory, but slow. I dropped it because $10/mon
goes on forever.
Holux GPS crashed after 24 hours of use over 6 months. Holux, in spite of
their inbox warranty statement, will not warranty their deice except through
the dealer. The eBay dealer, first to sell a SiRF III GPS in the U.S., had
glowing reports when I bought it but disappeared in the 6 months. Rumor is
some company was cloning Holux GPS units.
After research, I chose an iTrek M6. It is four times the performance of the
Holux; fast start, easier Bluetooth bonding, etc.
If I could just get Google Mobile Maps to recognize the GPS in Mobile 5,
things would be great. If Cingular does a pass thru of the new Mobile 6,
things may improve.
| |
| John Navas 2007-02-16, 12:33 pm |
| On Thu, 15 Feb 2007 19:44:47 -0800, SMS <scharf.steven@geemail.com>
wrote in < 45d528b6$0$27176$742
ec2ed@news.sonic.net>:
>Shannon wrote:
>
>Cingular is unable to do this with the positioning technology that they
>use. Sprint and Verizon can do this.
Cingular actually can locate handsets, as mandated by E911, using
TruePosition U-TDOA.
>[SNIP usual anti-Cingular, pro-Verizon rant]
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| John Navas 2007-02-16, 12:33 pm |
| On Thu, 15 Feb 2007 20:57:17 -0800, SMS <scharf.steven@geemail.com>
wrote in < 45d539b4$0$27195$742
ec2ed@news.sonic.net>:
>Thurman wrote:
>
>
>Cingular and T-Mobile use a less accurate positioning system, called
>TDOA, which is accurate to about 350 feet (at least 95% of the time).
No citation.
Cingular U-TDOA is actually accurate to better than 50 meters (150 feet)
98% of the time. <http://www.trueposition.com/TrueNorth-utdoa.php>
>The Verizon GPS system is at least twice as accurate (about 150 feet)
>and in most cases is accurate to 50 feet or better.
No citation.
Verizon A-GPS (assisted, not pure, GPS) is actually not that accurate,
especially when there's no clear line of sight to GPS satellites. Rated
accuracy is the same as U-TDOA (50 meters, 67% of the time).
<http://en.wikipedia.org/wiki/Assisted_GPS>
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
|
| John Navas wrote:
> On Thu, 15 Feb 2007 20:57:17 -0800, SMS <scharf.steven@geemail.com>
> wrote in < 45d539b4$0$27195$742
ec2ed@news.sonic.net>:
>
>
> No citation.
>
> Cingular U-TDOA is actually accurate to better than 50 meters (150 feet)
> 98% of the time. <http://www.trueposition.com/TrueNorth-utdoa.php>
>
>
> No citation.
>
> Verizon A-GPS (assisted, not pure, GPS) is actually not that accurate,
> especially when there's no clear line of sight to GPS satellites. Rated
> accuracy is the same as U-TDOA (50 meters, 67% of the time).
> <http://en.wikipedia.org/wiki/Assisted_GPS>
>
The rumor I heard is currently gearing up to offer AGPS/LBS services. I
presume they'll leverage their existing TP system for it. As to what
adjunct services will be available...
--
jer
email reply - I am not a 'ten'
| |
| John Navas 2007-02-16, 12:33 pm |
| On Fri, 16 Feb 2007 12:22:27 -0600, Jer <gdunn@airmail.ten> wrote in
< 12tbtitmrarq9b9@corp
.supernews.com>:
>John Navas wrote:
[color=darkred]
>The rumor I heard is currently gearing up to offer AGPS/LBS services. I
>presume they'll leverage their existing TP system for it. As to what
>adjunct services will be available...
Cingular supports A-GPS only on certain handsets (e.g., Nokia E62,
Intermec 761). Most GSM handsets don't have A-GPS capability.
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
|
| Jer wrote:
> The rumor I heard is currently gearing up to offer AGPS/LBS services. I
> presume they'll leverage their existing TP system for it. As to what
> adjunct services will be available...
Huh, who is gearing up? I know that the GSM carriers in Europe are doing
this, but I haven't heard of Cingular or T-Mobile doing it.
The adjunct services when it's available will be the same as the
services that Sprint/Nextel, and Verizon can offer now, location based
services such as tracking field service employees, tracking your kids, etc.
The GSM carriers were in a rush to meet the FCC E911 requirements, and
did the minimum they could with their TDOA system. They really have no
choice but to eventually upgrade to a GPS based system, if they want to
go after the high-value corporate customers that need the adjunct services.
| |
|
| SMS wrote:
> Jer wrote:
>
>
> Huh, who is gearing up? I know that the GSM carriers in Europe are doing
> this, but I haven't heard of Cingular or T-Mobile doing it.
>
> The adjunct services when it's available will be the same as the
> services that Sprint/Nextel, and Verizon can offer now, location based
> services such as tracking field service employees, tracking your kids, etc.
>
> The GSM carriers were in a rush to meet the FCC E911 requirements, and
> did the minimum they could with their TDOA system. They really have no
> choice but to eventually upgrade to a GPS based system, if they want to
> go after the high-value corporate customers that need the adjunct services.
The way I've heard it, LBS doesn't necessarily require the accuracy of a
GPS-capable handset. Existing TDOA metrics meet FCC minimums, so a
marketer, with Assisted GPS service, could offer text messaging to
handsets that fall within a specific geographic area, assuming the
handset owner has opted in to receive such.
--
jer
email reply - I am not a 'ten'
| |
| Todd Allcock 2007-02-16, 10:33 pm |
| At 16 Feb 2007 17:43:08 +0000 John Navas wrote:
> Cingular U-TDOA is actually accurate to better than 50 meters (150 feet)
> 98% of the time. <http://www.trueposition.com/TrueNorth-utdoa.php>
Actually you combined two individual data points there- the 98% was
"yield"- the percentage of time location could be established, and the
"under 50 meters" was the best-case accuracy - they don't claim the two
together!
They simply claim their performance "exceeds the FCC E-911 Phase II
accuracy requirements in virtually any environment." (67% of calls
within 100 meters and 95% of calls within 300 meters.)
> Verizon A-GPS (assisted, not pure, GPS) is actually not that accurate,
> especially when there's no clear line of sight to GPS satellites. Rated
> accuracy is the same as U-TDOA (50 meters, 67% of the time).
> <http://en.wikipedia.org/wiki/Assisted_GPS>
Nothing on that page seemed to discuss the accuracy of A-GPS that I saw.
Ironically, the first thing that page DID display was "This article or
section does not cite its references or sources." ;-)
| |
|
| Todd Allcock wrote:
> They simply claim their performance "exceeds the FCC E-911 Phase II
> accuracy requirements in virtually any environment." (67% of calls
> within 100 meters and 95% of calls within 300 meters.)
Right, 300 meters is the accuracy, not 50 meters.
> Ironically, the first thing that page DID display was "This article or
> section does not cite its references or sources." ;-)
The V325/V325i is a true GPS phone, with accuracies down in the 10 meter
range.
It's becoming very popular for location based services. I was surprised
that it included AMPS support, until my wife told me that her company
was buying hundreds of these phones, not only for the GPS, but for the
AMPS coverage. Her company sends field people to the nether regions of
the Bay Area counties, and AMPS is often all that's available (their old
Nextel system was worthless).
| |
| Todd Allcock 2007-02-17, 4:33 am |
| At 16 Feb 2007 23:26:07 -0800 SMS wrote:
> Right, 300 meters is the accuracy, not 50 meters.
No, actually John was partially correct- the GSM locator system he
referenced is in use by Cingular and T-Mobile and provides accuracy
_up_to_ 50 meters. Just not 95% of the time.
Either way, it's immaterial to the topic at hand- 50-300 meters is good
enough for many location-based applications, but Cingular and T-Mo
currently do not offer any I'm aware of (but AT&T Wireless used to over
GSM- they offered a Disney Mobile-esque "buddy locator" service long
before the Mouse went mobile!)
--
Posted via a free Usenet account from http://www.teranews.com
| |
|
| Todd Allcock wrote:
> At 16 Feb 2007 23:26:07 -0800 SMS wrote:
>
>
> No, actually John was partially correct- the GSM locator system he
> referenced is in use by Cingular and T-Mobile and provides accuracy
> _up_to_ 50 meters. Just not 95% of the time.
Right, that's what I said. "Cingular and T-Mobile use a less accurate
positioning system, called TDOA, which is accurate to about 350 feet (at
least 95% of the time)."
TruePosition's U-TDOA Location Solution Provides High Accuracy ...
within 47.1 meters 67% of the time, and within 112.2 meters 95% of the time.
For location based services, the 112 meters is unusable. You can't be
that far off 33% of the time when you're implementing an ITS system.
I'm sure that Cingular will deploy a GPS based system eventually. Many
of the European GSM carriers are doing this even though it's not a
government requirement.
| |
| Todd Allcock 2007-02-17, 4:33 am |
|
"SMS" <scharf.steven@geemail.com> wrote in message
news:45d6c502$0$2715
5$742ec2ed@news.sonic.net...
>
> Right, that's what I said. "Cingular and T-Mobile use a less accurate
> positioning system, called TDOA, which is accurate to about 350 feet (at
> least 95% of the time)."
Ah, I missed the nuance. I assumed you meant the accuracy was always ~ 350
feet.
> TruePosition's U-TDOA Location Solution Provides High Accuracy ...
> within 47.1 meters 67% of the time, and within 112.2 meters 95% of the
> time.
>
> For location based services, the 112 meters is unusable. You can't be that
> far off 33% of the time when you're implementing an ITS system.
That's too broad a statement- it depends on the application of the data. If
I want to know if my son is at his friend's house like he said, rather than
at the mall or the arcade, 350 feet is fine. In fact, off the top of my
head, I can envision plenty of applications for which 350 feet is plenty
usable. I'd agree in-car navigation isn't one of them, because determining
exactly which street someone is on would be dicey, but if a service company
wants to know which employee is closest to an emergency call, or a parcel
company wants to dispatch the nearest truck to an address for a pick-up,
again, 350 would do it easily. I'll conceed, however, that if I want to
know if my employee stopped at the local bar instead of the deli next door
for his lunch, or we want to know exactly which room Mr. Bond has
infiltrated in SPECTRE's headquarters, 350 feet leaves much to be desired!
> I'm sure that Cingular will deploy a GPS based system eventually. Many of
> the European GSM carriers are doing this even though it's not a government
> requirement.
As GPS chipsets drop in price, AND an actual demand is there, perhaps. But
since the most likely to be adopted widespread uses of location services
will be gaming, kiddie tracking and targeted-advertising (spam!) I'm not
sure Cingular needs to invest in more accuracy. It might be cheaper to let
the niche customers like your wife's employer walk away, than upgrade an
entire system for very little return.
Besides, as "real" GPS receivers (not relying on tower position or
off-handset calculation like A-GPS) become more common in handsets, the
handset manufacturers might want a piece of the action formerly reserved for
carriers. It's easy to envision Nokia, Microsoft, or Palm customizing apps
or at least an API so they or third parties could sell location based
services- why move the family plan to Disney Mobile if Nokia sets their
phones up to send the GPS data to a Nokia server via GPRS or SMS that I can
access from my phone via a low cost subscription? Like ringtones or
international LD, GPS tracking data might eventually become a competitve
marketplace, not solely in the province of wireless carriers.
--
Posted via a free Usenet account from http://www.teranews.com
| |
|
| Todd Allcock wrote:
> That's too broad a statement- it depends on the application of the data. If
> I want to know if my son is at his friend's house like he said, rather than
> at the mall or the arcade, 350 feet is fine. In fact, off the top of my
> head, I can envision plenty of applications for which 350 feet is plenty
> usable. I'd agree in-car navigation isn't one of them, because determining
> exactly which street someone is on would be dicey, but if a service company
> wants to know which employee is closest to an emergency call, or a parcel
> company wants to dispatch the nearest truck to an address for a pick-up,
> again, 350 would do it easily. I'll conceed, however, that if I want to
> know if my employee stopped at the local bar instead of the deli next door
> for his lunch, or we want to know exactly which room Mr. Bond has
> infiltrated in SPECTRE's headquarters, 350 feet leaves much to be desired!
Sad to say, but many businesses do want to know exactly where the
employee is, to withing a few feet.
>
> As GPS chipsets drop in price, AND an actual demand is there, perhaps. But
> since the most likely to be adopted widespread uses of location services
> will be gaming, kiddie tracking and targeted-advertising (spam!) I'm not
> sure Cingular needs to invest in more accuracy.
For non-business users you're correct. But businesses are deploying most
of these systems to track field employees. It's not just to be big
brother, in some cases it's to ensure that the field people are not
violating any confidentiality regulations by stopping by the local
Starbucks to do their paperwork in a non-secure environment.
> It might be cheaper to let
> the niche customers like your wife's employer walk away, than upgrade an
> entire system for very little return.
Perhaps, but this is an employer with tens of thousands of field
employees across the country, and if the field trial is successful it
means tens of thousands of new high ARPU customers. And that's just one
employer.
> Besides, as "real" GPS receivers (not relying on tower position or
> off-handset calculation like A-GPS) become more common in handsets, the
> handset manufacturers might want a piece of the action formerly reserved for
> carriers.
Verizon will be quick to eliminate this possibility with defeatured
handsets.>
| |
| tmoran@acm.org 2007-02-17, 3:33 pm |
| My year old hand-held GPS doesn't work in my house, or under the trees
outside when they're wet. Is the GPS in cell phones much better?
| |
|
| tmoran@acm.org wrote:
> My year old hand-held GPS doesn't work in my house, or under the trees
> outside when they're wet. Is the GPS in cell phones much better?
The short answer is no, they won't. A GPS receiver will always be
problematic in an overhead environment, ie. covered/underground parking
structure, building, tunnel, heavy/wet foliage, etc. A higher number of
sat channels available improves things, but I don't know how many sat
channels a cell phone uses. Anybody know?
--
jer
email reply - I am not a 'ten'
| |
| Todd Allcock 2007-02-17, 10:33 pm |
| At 16 Feb 2007 09:34:44 -0600 Thurman wrote:
> After research, I chose an iTrek M6. It is four times the performance
of the
> Holux; fast start, easier Bluetooth bonding, etc.
>
> If I could just get Google Mobile Maps to recognize the GPS in Mobile
5,
> things would be great.
Google doesn't "look" for your GPS- it relies on the OS "telling" GMM
where it is.
Unfortunately the settings applet to do this is hidden- to get it back,
you'll need a registry editor, and make the following changes:
Add a new DWORD in " HKLM\ControlPanel\GP
S Settings" named "Group" and set
it to 2.
Delete the " HKLM\ControlPanel\GP
S Settings\redirect" key. (I think it's
called "Hide" instead of "redirect" on some devices- whichever it's called,
delete it!)
> If Cingular does a pass thru of the new Mobile 6,
> things may improve.
Unless it stays hidden in WM6 as well! ;-)
After making the changes, exit the editor, wait a few seconds (registry
writes take awhile in WM5) then reset the phone. Now go into Settings >
Connections and select "External GPS" and setup the port your BT GPS
connects to.
| |
| Todd Allcock 2007-02-17, 10:33 pm |
| At 17 Feb 2007 14:33:06 -0600 Jer wrote:
> A higher number of sat channels available improves things, but I don't
know how many sat channels a cell phone uses. Anybody know?
Well, given that this is a Cingular NG, that's an easy one: zero channels.
Cingular and T-Mobile use a cell tower-triangulation based system.
Sprint and Verizon use an "asssisted GPS" system that uses a GPS
satellite receiver chip in the phone along with info from nearby towers
to quicken the time to get a fix to just a few seconds, as opposed to the
30-90 seconds a GPS takes to get a first fix on a cold start.
I don't think those phones use many channels, but they don't really have
to- the "assist" from the towers is that the phone is told by the tower
which satellites are overhead and their approximate positions, so the GPS
doesn't have to waste time searching, or reading more sats than necessary.
--
Posted via a free Usenet account from http://www.teranews.com
| |
| Todd Allcock 2007-02-17, 10:33 pm |
| At 17 Feb 2007 03:23:00 -0800 SMS wrote:
off-handset calculation like A-GPS) become more common in handsets, the
handset manufacturers might want a piece of the action formerly reserved
for carriers.[color=darkred]
>
> Verizon will be quick to eliminate this possibility with defeatured
handsets.>
That's the beauty of competition- if Verizon crippled their handsets to
prevent potentially better location-based systems from being used, those
same companies embracing Verizon service now might leave for other
carriers that don't block such services.
Correct me if I'm wrong, but to comply with E911 rules, current handsets
trade accuracy for speed in order to get a quicker fix (part of E911
compliance.) It would seem to me that a much cheaper and more accurate
system could easily be devised by writing a custom app (either in-house
or contracted) to relay real-time satellite GPS data via GPRS/EVDO
directly back to the company. This would require either a handset with a
built-in satellite GPS, like some of the high-end WinMo devices, or for
lower-cost, perhaps a java-based data relay app on a "stock" BT handset
using an external BT GPS (left in the employee's vehicle.)
Leaving the actual "tracking device" (the BT GPS) in the vehicle
eliminates the Orwellian info your wife's outfit is trying to collect,
but the vast majority of companies using this type of system is trying to
coordinate delivery, pickup, or dispatching- not to catch which employees
are stopping at 7-11 for a Zagnut bar on the way to their next meeting.
Verizon is getting $30-50/month/employee on top of cellular service fees
for their "field management" tracking system. For an organization like
your wife's, with tens of thousands of potential trackees, the cost
savings of an in-house system could be huge over a relatively short period,
I would think.
--
Posted via a free Usenet account from http://www.teranews.com
| |
|
| Todd Allcock wrote:
> At 17 Feb 2007 14:33:06 -0600 Jer wrote:
> know how many sat channels a cell phone uses. Anybody know?
>
>
> Well, given that this is a Cingular NG, that's an easy one: zero channels.
>
> Cingular and T-Mobile use a cell tower-triangulation based system.
>
> Sprint and Verizon use an "asssisted GPS" system that uses a GPS
> satellite receiver chip in the phone along with info from nearby towers
> to quicken the time to get a fix to just a few seconds, as opposed to the
> 30-90 seconds a GPS takes to get a first fix on a cold start.
>
> I don't think those phones use many channels, but they don't really have
> to- the "assist" from the towers is that the phone is told by the tower
> which satellites are overhead and their approximate positions, so the GPS
> doesn't have to waste time searching, or reading more sats than necessary.
Perhaps you missed my other post... my Cingular bud tells me they're
currently ramping up for AGPS/LBS service, so I presume Cingular will
eventually be offering newer handsets for this. Maybe Cingular's phones
will use more sat channels than the others.
--
jer
email reply - I am not a 'ten'
| |
| Todd Allcock 2007-02-18, 4:33 am |
| At 17 Feb 2007 22:29:01 -0600 Jer wrote:
> Perhaps you missed my other post... my Cingular bud tells me they're
> currently ramping up for AGPS/LBS service, so I presume Cingular will
> eventually be offering newer handsets for this. Maybe Cingular's phones
> will use more sat channels than the others.
I did miss your other post, sorry.
While I applaud Cingular for upgrading their technology, does any company
in the industry deploy more stuff only to rip it out or upgrade it into
obsolesence shortly afterwards than Cingular? ;-)
--
Posted via a free Usenet account from http://www.teranews.com
| |
| Dennis Ferguson 2007-02-18, 4:33 am |
| On 2007-02-18, Todd Allcock < elecconnec@AmericaOn
Line.com> wrote:
> At 17 Feb 2007 14:33:06 -0600 Jer wrote:
> know how many sat channels a cell phone uses. Anybody know?
>
> Well, given that this is a Cingular NG, that's an easy one: zero channels.
>
> Cingular and T-Mobile use a cell tower-triangulation based system.
>
> Sprint and Verizon use an "asssisted GPS" system that uses a GPS
> satellite receiver chip in the phone along with info from nearby towers
> to quicken the time to get a fix to just a few seconds, as opposed to the
> 30-90 seconds a GPS takes to get a first fix on a cold start.
Note that these aren't quite the same thing. CDMA networks have been
able to do tower-triangulation for a long time, just about for free.
That is, all CDMA base stations have clocks that are time synchronized
with GPS, code acquisition gives you a precise measurement of signal
arrival times, and in CDMA networks multiple towers track any handsets
they hear anyway to implement soft handoff. Extra equipment to do
essentially the same thing has to be added to GSM base stations to match
the functionality (to be fair, I should mention that this probably works
a bit better in GSM networks; the handset power control that CDMA depends
on for scaling makes it less likely that distant towers will be able to hear
a handset).
The drawback of tower triangulation is, of course, that you can't get
a fix on the phone unless at least 3 towers can hear the phone.
GPS, on the other hand, can provide location information even with
only one tower near enough to hear the handset, but only if the phone
is in a position where it can see the GPS satellites. The techniques
are hence sort of complimentary; two imperfect techniques can give you
better information more of the time than one imperfect technique.
Dennis Ferguson
| |
| Todd Allcock 2007-02-18, 4:33 am |
| At 18 Feb 2007 01:33:47 -0600 Dennis Ferguson wrote:
> Note that these aren't quite the same thing. CDMA networks have been
> able to do tower-triangulation for a long time, just about for free.
> That is, all CDMA base stations have clocks that are time synchronized
> with GPS, code acquisition gives you a precise measurement of signal
> arrival times, and in CDMA networks multiple towers track any handsets
> they hear anyway to implement soft handoff.
Just curious- why don't you think Verizon or Sprint leveraged this to
comply with the E911 deadline rather than commit to a GPS based solution?
--
Posted via a free Usenet account from http://www.teranews.com
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| Dennis Ferguson 2007-02-18, 7:33 am |
| On 2007-02-18, Todd Allcock < elecconnec@AmericaOn
Line.com> wrote:
> At 18 Feb 2007 01:33:47 -0600 Dennis Ferguson wrote:
>
>
> Just curious- why don't you think Verizon or Sprint leveraged this to
> comply with the E911 deadline rather than commit to a GPS based solution?
I'm not sure I know the answer to that. I do know the original IS-95
CDMA was only capable of measuring code acquisition delays with a
precision of one 1.25 MHz chip, or about 240 meters, which wasn't good
enough for E911. Some sort of modification was needed to improve this,
and I guess the modification they decided upon included the GPS receiver.
Since Qualcomm does most of the silicon for CDMA2000 phones, as soon
as they added GPS to the chip sets it was immediately available for all
new phone designs, so I guess there wasn't much reason not to do it.
Google found the following description of what is done:
http://www.snaptrack.com/pdf/ ion20.../>
rid_agps.pdf
They indeed use both GPS and ToA data to compute positions, depending
on what is available. There's a pie chart in there, built from the
results of early testing, showing that 84% of all position requests
were satisfied by AGPS data, 9% by time-of-arrival measurement and
7% by direction-finding from the tower.
Dennis Ferguson
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| Todd Allcock wrote:
> At 17 Feb 2007 22:29:01 -0600 Jer wrote:
>
>
> I did miss your other post, sorry.
>
> While I applaud Cingular for upgrading their technology, does any company
> in the industry deploy more stuff only to rip it out or upgrade it into
> obsolesence shortly afterwards than Cingular? ;-)
Cingular was forced into this situation by the E911 requirements of the
FCC which would not extend the deadline for compliance. The TDOA system
was relatively fast and cheap to deploy.
Assisted GPS is much more accurate, typically to 10M, but apparently
wasn't easily integrated with the existing GSM chipsets.
Qualcomm, the company that everyone loves to hate, came through for the
CDMA carriers in time for Phase II of E-911.
A-GPS is a huge marketing advantage in terms of sales to some large
corporate customers.
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|
| Todd Allcock wrote:
> At 18 Feb 2007 01:33:47 -0600 Dennis Ferguson wrote:
>
>
> Just curious- why don't you think Verizon or Sprint leveraged this to
> comply with the E911 deadline rather than commit to a GPS based solution?
I think that since the A-GPS technology was available from Qualcomm for
CDMA chipsets that the CDMA carriers were convinced that the higher
accuracy of A-GPS would enable them to win more customers, especially
high value customers. Disney Mobile, a Sprint MVNO, was marketing
location based services six months before they even launched their network.
For some corporate customers, accurate location based service is driving
their choice of carrier, and once they choose carriers, they aren't
going to easily change just because another carrier catches up. You see
that now with high speed data, Cingular is way behind Sprint and Verizon
in deployment, and has lost the early adopter market.
Whether the net return in A-GPS was worth the extra cost remains to be
seen. However it's often the case that you can market a product's
capability even to customers that initially aren't interested in using
that capability, but might possibly want to use it. I remember when I
worked in product marketing for a Taiwanese motherboard company. We
wasted so much money in adding future capability to boards, such as
Weitek math co-processor sockets, and even sockets so you could upgrade
from a 386 to a 486 processor. The number of customers that ever used
these sockets was close to zero, but it won us huge contracts for boards.
[Copied to alt.cellular.attws. Please post all alt.cellular.cingular
posts to alt.cellular.attws as well. The Cingular name is going away,
and alt.cellular.attws is the proper venue for posts regarding AT&T's
Wireless Service.]
| |
| Thurman 2007-02-18, 12:33 pm |
|
"Todd Allcock" < elecconnec@AmericaOn
Line.com> wrote in message
news:er7vdf$ir4$1@ai
oe.org...
> At 16 Feb 2007 09:34:44 -0600 Thurman wrote:
>
> of the
> 5,
>
> Google doesn't "look" for your GPS- it relies on the OS "telling" GMM
> where it is.
>
> Unfortunately the settings applet to do this is hidden- to get it back,
> you'll need a registry editor, and make the following changes:
>
> Add a new DWORD in " HKLM\ControlPanel\GP
S Settings" named "Group" and set
> it to 2.
>
>
> Delete the " HKLM\ControlPanel\GP
S Settings\redirect" key. (I think it's
> called "Hide" instead of "redirect" on some devices- whichever it's
> called,
> delete it!)
>
>
>
> Unless it stays hidden in WM6 as well! ;-)
>
> After making the changes, exit the editor, wait a few seconds (registry
> writes take awhile in WM5) then reset the phone. Now go into Settings >
> Connections and select "External GPS" and setup the port your BT GPS
> connects to.
I really appreciate that info. However, I'm reluctant to risk bricking a
$500+ investment.
| |
| Todd Allcock 2007-02-18, 3:33 pm |
| At 18 Feb 2007 10:53:37 -0600 Thurman wrote:
> I really appreciate that info. However, I'm reluctant to risk bricking
a
> $500+ investment.
While I understand your concern, registry edits aren't harmful to hardware.
Worst-case scenario, if you really muck something up, you'd have to
"hard-reset" (which erases everything you've put on it and returns it to
out-of-the-box" condition.
Flashing new ROM updates to the device can brick them if somethings goes
awry.
Frankly, I've never owned a Pocket PC/WinMobile that didn't need, or at
least benefitted from a little registry tweaking.
My guess is that HTC (the maker of the Cingular 8525, 8125, 3125, 2125, T-
Mo MDA, SDA, Dash, etc.) left this control hidden at Cingular's (and T-
Mobile's) request so as not to confuse customers into thinking there was
a GPS built-in.
The real advantage of activating the control, besides GMM working, is
that multiple GPS apps can all use the data simultaneously. I'll often
run Mapopolis for my actual navigation, but occasionally fire up GMM or
WLM to get local business info. It's nice not having to shut one down to
use the other.
--
Posted via a free Usenet account from http://www.teranews.com
| |
| Thurman 2007-02-18, 10:33 pm |
|
"Todd Allcock" < elecconnec@AmericaOn
Line.com> wrote in message
news:45d8988a$0$1640
4$88260bb3@free.teranews.com...
> At 18 Feb 2007 10:53:37 -0600 Thurman wrote:
>
> My guess is that HTC (the maker of the Cingular 8525, 8125, 3125, 2125, T-
> Mo MDA, SDA, Dash, etc.) left this control hidden at Cingular's (and T-
> Mobile's) request so as not to confuse customers into thinking there was
> a GPS built-in.
They may have excluded the connection to encourage 'rentals' of TeleNav.
I had DeLorme, Pocket Streets and MySportTraining GPS all working. It was
easy to switch among the 3, but it took me a couple of days of experimenting
to get Telenav to work. One TeleNav started working, the other 3 stopped as
if they were blocked. Telenav for professional use is a good product, but
their destination database seems lacking and the GUI could sue some work.
> The real advantage of activating the control, besides GMM working, is
> that multiple GPS apps can all use the data simultaneously. I'll often
> run Mapopolis for my actual navigation, but occasionally fire up GMM or
> WLM to get local business info. It's nice not having to shut one down to
> use the other.
GPS Gate is recommended for that. I'll try a trial download.
Thanks again.
Have you tried exporting logs to WinXP Google Earth?
| |
| 3Gfreak 2007-02-18, 10:33 pm |
| On Feb 15, 9:44 pm, SMS <scharf.ste...@geemail.com> wrote:
> Shannon wrote:
>
> Cingular is unable to do this with the positioning technology that they
> use. Sprint and Verizon can do this.
>
> Some European GSM carriers are deploying technology that allows this,
> but I doubt if Cingular intends to deploy it any time soon. They have
> their hands full now with their HSDPA deployment.
>
> My wife's company just switched to Verizon, and one reason was that they
> wanted the tracking capability. They used to be on Nextel, but the
> coverage wasn't good, as they routinely go to very rural parts of the
> county, so they needed AMPS and CDMA.
The beauty with Cingular is that it is GSM and the technology is
already in place for them to be able to track ones phone. In fact if
you pay close attention you will see this feature launched in the near
future.
3GFreak
www.mobilevertigo.com
| |
| clifto 2007-02-19, 10:33 am |
| SMS wrote:
> Todd Allcock wrote:
>
> Cingular was forced into this situation by the E911 requirements of the
> FCC which would not extend the deadline for compliance. The TDOA system
> was relatively fast and cheap to deploy.
Now, I figured the solution to that for Cingular would be to tell their
customers their phones would be shut off in thirty days, and that they
could replace them at any Cingular store for full retail price.
--
"Nowadays, security guys break the Mac every single day. Every single day,
they come out with a total exploit, your machine can be taken over totally.
I dare anybody to do that once a month on the Windows machine."
-- Bill Gates, in an interview with Newsweek's Steven Levy
| |
| clifto 2007-02-19, 10:33 am |
| SMS wrote:
> Todd Allcock wrote:
>
> Right, that's what I said. "Cingular and T-Mobile use a less accurate
> positioning system, called TDOA, which is accurate to about 350 feet (at
> least 95% of the time)."
>
> TruePosition's U-TDOA Location Solution Provides High Accuracy ...
> within 47.1 meters 67% of the time, and within 112.2 meters 95% of the time.
So they can place you within a 6700 square foot area sometimes, but usually
more like within 33,876 square feet. Great in those supermarket parking
lots and hillside forested areas. I suppose it's better than nothing, but
it sure looks like one of those situations where the cheapest thing that
sorta kinda looks like it works is adopted.
Not that the assisted GPS is any better in a rollover accident. I
remember the time I watched my GPS as my apartment building flew at
650 MPH from a suburb of Chicago to somewhere south of Lafayette IN,
and the GPS quit when the building hit the GPS limit of 100,000 feet
altitude (incomplete view of the sky and the satellite constellation).
--
"Nowadays, security guys break the Mac every single day. Every single day,
they come out with a total exploit, your machine can be taken over totally.
I dare anybody to do that once a month on the Windows machine."
-- Bill Gates, in an interview with Newsweek's Steven Levy
| |
| Todd Allcock 2007-02-19, 12:33 pm |
| At 18 Feb 2007 15:50:41 -0600 Thurman wrote:
> Have you tried exporting logs to WinXP Google Earth?
No, I've never tried it. Frankly I rarely use Google Earth on the desktop.
--
Posted via a free Usenet account from http://www.teranews.com
| |
|
| In article <b9soa4-jg3.ln1@remote.clifto.com>,
clifto <clifto@gmail.com> wrote:
> SMS wrote:
>
> So they can place you within a 6700 square foot area sometimes, but usually
> more like within 33,876 square feet. Great in those supermarket parking
> lots and hillside forested areas. I suppose it's better than nothing, but
> it sure looks like one of those situations where the cheapest thing that
> sorta kinda looks like it works is adopted.
>
> Not that the assisted GPS is any better in a rollover accident. I
> remember the time I watched my GPS as my apartment building flew at
> 650 MPH from a suburb of Chicago to somewhere south of Lafayette IN,
> and the GPS quit when the building hit the GPS limit of 100,000 feet
> altitude (incomplete view of the sky and the satellite constellation).
You need at least 3 satellites in a clear shot to get any kind of decent
tracking. The more satellites you get, the more accurate. My Garmin
Etrex averages about 6 out of 11 at any one time. The more satellites,
the more accurate. (3= 58ft., 4= 32ft., etc.)
How many do these claim to pick up?
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