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Re: 911 Call location accuracy
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| Dennis Ferguson 2007-04-29, 10:33 pm |
| On 2007-04-29, John Navas < spamfilter1@navasgro
up.com> wrote:
> On Sat, 28 Apr 2007 13:24:22 -0700, Evan Platt
><evan@theobvious.espphotography.com> wrote in
>< dab733hvffo2ndg6btlg
cm1krmbpd7grh7@4ax.com>:
>
>
> Actually not.
>
>
> AT&T/Cingular E911 positioning is actually done by U-TDOA. I suggest
> you read up on it in order to avoid making more inaccurate statements.
> See links in the Cingular FAQ below.
So are you saying you can do TDOA positioning with fewer than three
tower measurements? How?
I know it can fall back to direction-and-signal-strength ranging when
it has less than 3 towers to work with, but these measurements are crap.
>
> The A-GPS (Assisted GPS) used in cell phones isn't that accurate, and
> doesn't work at all in many locations, including many urban areas, under
> tree cover, indoors, etc. Again, you clearly need to read up on the
> technology in order to avoid making inaccurate statements.
Have you seen any A-GPS in use in cell phones other than Qualcomm's?
The SnapTrack Wireless Assisted GPS(TM) is actually a hybrid which takes
TOA measurements from both available GPS satellites and from all the
towers it can hear, and reports all these to the network. In the case
where it can't hear any GPS satellites it continues to work but makes
do with tower-based data alone like the Cingular system (I hope you aren't
defining "working like Cingular" as "not working"). If it can also
measure GPS satellite TOAs it works even better.
Dennis Ferguson
| |
|
| Dennis Ferguson wrote:
> Have you seen any A-GPS in use in cell phones other than Qualcomm's?
> The SnapTrack Wireless Assisted GPS(TM) is actually a hybrid which takes
> TOA measurements from both available GPS satellites and from all the
> towers it can hear, and reports all these to the network. In the case
> where it can't hear any GPS satellites it continues to work but makes
> do with tower-based data alone like the Cingular system (I hope you aren't
> defining "working like Cingular" as "not working"). If it can also
> measure GPS satellite TOAs it works even better.
>
> Dennis Ferguson
Yes, Verizon is using Snaptrack and the accuracy is very very good, and
the hybrid design ensures that it works indoors as well. I only know one
company that's using location based services, but it's very large, and
they chose Verizon based mainly on their need for accurate positioning.
They've been getting accuracy to about 15 meters. The TDOA system used
by Cingular has much poorer accuracy. Cingular has promised that they
will be implementing a more accurate system in the future, not later
than the end of 2008.
Companies that need to implement location based services are flocking to
the CDMA carriers because the GSM carriers (at least in the U.S.) have
not yet implemented Snaptrack (or similar systems).
[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.]
| |
| John Navas 2007-04-30, 10:33 pm |
| On Sun, 29 Apr 2007 18:42:00 -0500, Dennis Ferguson
<dcferguson@pacbell.net> wrote in
<slrnf3aba8.85.dcferguson@akit-ferguson.com>:
>On 2007-04-29, John Navas < spamfilter1@navasgro
up.com> wrote:
[color=darkred]
>
>So are you saying you can do TDOA positioning with fewer than three
>tower measurements?
Yes.
>How?
As I wrote, read up on it. Also on sector antennas. Likewise position
mapping.
>I know it can fall back to direction-and-signal-strength ranging when
>it has less than 3 towers to work with, but these measurements are crap.
You would be misinformed.
>
>Have you seen any A-GPS in use in cell phones other than Qualcomm's?
Yes.
>The SnapTrack Wireless Assisted GPS(TM) is actually a hybrid which takes
>TOA measurements from both available GPS satellites and from all the
>towers it can hear, and reports all these to the network. In the case
>where it can't hear any GPS satellites it continues to work but makes
>do with tower-based data alone like the Cingular system (I hope you aren't
>defining "working like Cingular" as "not working"). If it can also
>measure GPS satellite TOAs it works even better.
Read world results are considerably less accurate and reliable than you7
suggest.
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| John Navas 2007-04-30, 10:33 pm |
| On Sun, 29 Apr 2007 17:15:23 -0700, SMS <scharf.steven@geemail.com>
wrote in < 4635351b$0$27181$742
ec2ed@news.sonic.net>:
>Companies that need to implement location based services are flocking to
>the CDMA carriers because the GSM carriers (at least in the U.S.) have
>not yet implemented Snaptrack (or similar systems).
Proof? Or another of your fantasies?
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| Dennis Ferguson 2007-04-30, 10:33 pm |
| On 2007-04-30, John Navas < spamfilter1@navasgro
up.com> wrote:
> On Sun, 29 Apr 2007 18:42:00 -0500, Dennis Ferguson wrote:
>
> As I wrote, read up on it. Also on sector antennas. Likewise position
> mapping.
Exactly. Like I said, crap. Of course A-GPS systems can do this too,
and the measurements are just as crappy. They just don't need to do
it as often.
>
> Yes.
So which A-GPS have you seen which doesn't work indoors?
>
> Read world results are considerably less accurate and reliable than you7
> suggest.
Hey, what happened to your assertion that A-GPS systems didn't work indoors,
i.e.
> The A-GPS (Assisted GPS) used in cell phones isn't that accurate, and
> doesn't work at all in many locations, including many urban areas, under
> tree cover, indoors, etc. Again, you clearly need to read up on the
> technology in order to avoid making inaccurate statements.
? I'd like to read up on that.
I didn't suggest any level of accuracy and reliability other than it
is at least as good as U-TDOA. Good luck proving otherwise.
Dennis Ferguson
| |
|
| Dennis Ferguson wrote:
> I didn't suggest any level of accuracy and reliability other than it
> is at least as good as U-TDOA. Good luck proving otherwise.
Someone had better tell the sales people trying to sell LBS systems
based on U-TDOA about Navas's claims. The big selling point of the
Snaptrack based LBS systems is the much higher accuracy, while the
U_TDOA systems are being sold solely on lower cost.
You also have all those European carriers needlessly implementing hybrid
systems because they foolishly failed to consult with the self-appointed
expert on everything. They could have saved a lot of money if only
someone had told them that U-TDOA could provide sufficiently accurate
positioning for their LBS applications, without the need for more
expensive handsets, and without the need for all the infrastructure.
I can think of one big advantage of the U-TDOA LBS systems, they'd cause
less union opposition due to their lower accuracy. The union workers
that are being tracked with the Snaptrack system are not happy about it.
[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.]
| |
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 16:07:19 -0500, Dennis Ferguson
<dcferguson@pacbell.net> wrote in
<slrnf3cmk6.86.dcferguson@akit-ferguson.com>:
>On 2007-04-30, John Navas < spamfilter1@navasgro
up.com> wrote:
>
>Exactly. Like I said, crap.
In fact the position accuracy of TruePosition U-TDOA (as used by
AT&T/Cingular) with two receivers and reception angle is good, on par
with accuracy with three receivers (where angle data isn't needed).
Angle data is what makes the difference.
>Of course A-GPS systems can do this too,
>and the measurements are just as crappy. They just don't need to do
>it as often.
A-GPS depends on reception of GPS signals by the handset, which is a
problem in many locations (urban canyons, under tree cover, indoors,
etc.). Because of this serious weakness, hybrid A-GPS systems (e.g.,
SnapTrack) augment GPS, using Enhanced Cell-ID with CDMA200 that's
relatively crude as compared to U-TDOA with GSM.
>So which A-GPS have you seen which doesn't work indoors?
All of them. A-GPS requires GPS signals to work. Without such signals,
accuracy depends on how much the handset has moved since the last
position fix and on what other location data is available.
>I didn't suggest any level of accuracy and reliability other than it
>is at least as good as U-TDOA. Good luck proving otherwise.
Enhanced Cell-ID has an accuracy of only 75-500 meters, far less
accurate than U-TDOA as used in TruePosition U-TDOA.
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 14:34:04 -0700, SMS <scharf.steven@geemail.com>
wrote in < 463660cd$0$27246$742
ec2ed@news.sonic.net>:
>Dennis Ferguson wrote:
>
>
>Someone had better tell the sales people trying to sell LBS systems
>based on U-TDOA about Navas's claims. The big selling point of the
>Snaptrack based LBS systems is the much higher accuracy, while the
>U_TDOA systems are being sold solely on lower cost.
SnapTrack is actually quite a bit less accurate than U-TDOA when a GPS
fix isn't available (as is often the case; e.g., in urban canyons, under
tree cover, indoors, etc.) because it relies on relatively crude
Enhanced Cell-ID.
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| Dennis Ferguson 2007-04-30, 10:33 pm |
| On 2007-04-30, John Navas < spamfilter1@navasgro
up.com> wrote:
> On Mon, 30 Apr 2007 14:34:04 -0700, SMS <scharf.steven@geemail.com>
> wrote in < 463660cd$0$27246$742
ec2ed@news.sonic.net>:
>
>
> SnapTrack is actually quite a bit less accurate than U-TDOA when a GPS
> fix isn't available (as is often the case; e.g., in urban canyons, under
> tree cover, indoors, etc.) because it relies on relatively crude
> Enhanced Cell-ID.
For GSM networks with unmodified base station transmitters, maybe.
For (W)CDMA networks, where transmissions are time-synchronous (and
for GSM networks which have been made so), it uses Time of Arrival
measurements exactly like U-TDOA.
Dennis Ferguson
| |
|
| Dennis Ferguson wrote:
> For GSM networks with unmodified base station transmitters, maybe.
> For (W)CDMA networks, where transmissions are time-synchronous (and
> for GSM networks which have been made so), it uses Time of Arrival
> measurements exactly like U-TDOA.
This is correct.
More importantly, the big users of LBS systems are companies tracking
the location of field personnel, delivery trucks, etc., so there is no
issue with getting a satellite fix to enhance accuracy. At least in the
U.S. the LBS users did extensive field testing of the different
technologies, and the hybrid systems proved to be much more accurate.
For some applications, the lower accuracy of U-TDOA is acceptable, for
some it is not. This is the reason that the GSM carriers are deploying
hybrid systems.
| |
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 17:14:25 -0500, Dennis Ferguson
<dcferguson@pacbell.net> wrote in
<slrnf3cqi0.88.dcferguson@akit-ferguson.com>:
>On 2007-04-30, John Navas < spamfilter1@navasgro
up.com> wrote:
>
>For GSM networks with unmodified base station transmitters, maybe.
>For (W)CDMA networks, where transmissions are time-synchronous (and
>for GSM networks which have been made so), it uses Time of Arrival
>measurements exactly like U-TDOA.
Proof? SnapTrack states "Enhanced Cell ID".
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 15:31:12 -0700, SMS <scharf.steven@geemail.com>
wrote in < 46366e2f$0$27225$742
ec2ed@news.sonic.net>:
>Dennis Ferguson wrote:
>
>
>This is correct.
>
>More importantly, the big users of LBS systems are companies tracking
>the location of field personnel, delivery trucks, etc., so there is no
>issue with getting a satellite fix to enhance accuracy. At least in the
>U.S. the LBS users did extensive field testing of the different
>technologies, and the hybrid systems proved to be much more accurate.
>For some applications, the lower accuracy of U-TDOA is acceptable, for
>some it is not. This is the reason that the GSM carriers are deploying
>hybrid systems.
Proof? Or yet another made up claim?
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
|
|
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 18:18:23 -0500, Dennis Ferguson
<dcferguson@pacbell.net> wrote in
<slrnf3cu9v.7v.dcferguson@akit-ferguson.com>:
>On 2007-04-30, John Navas < spamfilter1@navasgro
up.com> wrote:
>
>I have other reasons to be familiar with how this works, however
>these will do:
>
> http://www.snaptrack.com/pdf/ ion20...br />
ation.pdf
> http://www.snaptrack.com/pdf/ ion20.../>
rid_agps.pdf
What matters, of course, is what's actually in the field, and how well
it performs in the real world.
<http://www.snaptrack.com/technology/index.jsp>
<http://www.cdmatech.com/docs_detail...one_hybrid.html>
Wireless Network
Base stations in the wireless network not only
provide communications coverage, but may
deliver adjunct locations information, such as
Enhanced Cell-ID that aids the location
process and ensures all-terrain availability of
location information.
<http://www.iec.org/online/tutorials/tcs/topic01.html>
Enhanced Cell-ID - Enhanced Cell-ID is a network technology that
combines Cell ID (CI) with one or more additional technologies. The
level of accuracy is increased over basic Cell ID, ranging from 75 -
500 meters. In GSM networks, CI can be combined with Timing Advance
(which measures handset range from the base station, including
whether or not the handset is connected to the nearest cell) and/or
Received Signal Level (which measures average signal strength). In
W-CDMA networks, CI can be combined with Round-Trip-Time (W-CDMA
version of Timing Advance) to improve accuracy.
>I do notice we've moved well beyond "doesn't work indoors".
On the contrary -- A-GPS simply doesn't work without GPS signals (e.g.,
in urban canyons, under tree cover, _indoors_) -- kindly refrain from
trying to put words in my mouth.
Hybrid A-GPS systems are a result of scrambling to overcome the serious
limitations of A-GPS-based positioning alone, which doesn't work well or
at all in many environments.
>Keep
>reading and you'll get up to speed.
Ditto.
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| Dennis Ferguson 2007-04-30, 10:33 pm |
| On 2007-04-30, John Navas < spamfilter1@navasgro
up.com> wrote:
> On Mon, 30 Apr 2007 16:07:19 -0500, Dennis Ferguson
><dcferguson@pacbell.net> wrote in
><slrnf3cmk6.86.dcferguson@akit-ferguson.com>:
>
>
>
> In fact the position accuracy of TruePosition U-TDOA (as used by
> AT&T/Cingular) with two receivers and reception angle is good, on par
> with accuracy with three receivers (where angle data isn't needed).
> Angle data is what makes the difference.
If you say so. Hybrid A-GPS doesn't need the angle to handle the
two tower case (it can be done just with timing information), only
the one tower case.
>
> A-GPS depends on reception of GPS signals by the handset, which is a
> problem in many locations (urban canyons, under tree cover, indoors,
> etc.). Because of this serious weakness, hybrid A-GPS systems (e.g.,
> SnapTrack) augment GPS, using Enhanced Cell-ID with CDMA200 that's
> relatively crude as compared to U-TDOA with GSM.
This would imply you've seen non-hybrid A-GPS implemented on some
cell phone (since that's what you said). Which one?
It's also wrong. In a CDMA network GPSone does TOA measurements
on the towers just like U-TDOA. The accuracy is 1/16 of a CDMA chip, or
about 15m for CDMA2000, though the vagarity of terrestrial RF paths
degrades this (just like U-TDOA).
>
> All of them. A-GPS requires GPS signals to work. Without such signals,
> accuracy depends on how much the handset has moved since the last
> position fix and on what other location data is available.
This would imply you've seen non-hybrid A-GPS implemented on some
cell phone (since that's what you said). Which one?
>
> Enhanced Cell-ID has an accuracy of only 75-500 meters, far less
> accurate than U-TDOA as used in TruePosition U-TDOA.
Proof?
Again, in networks with time-synchronous transmitters (which includes
all flavours of CDMA, and could include non-standard GSM made to do
so) TOA measurements are used, just like U-TDOA.
Dennis Ferguson
| |
| Scott 2007-04-30, 10:33 pm |
| John Navas < spamfilter1@navasgro
up.com> wrote in
news:sinc33596g3j388
1thcgp07sdlat5ccnsr@
4ax.com:
> On Mon, 30 Apr 2007 16:07:19 -0500, Dennis Ferguson
> <dcferguson@pacbell.net> wrote in
> <slrnf3cmk6.86.dcferguson@akit-ferguson.com>:
>
>
>
> In fact the position accuracy of TruePosition U-TDOA (as used by
> AT&T/Cingular) with two receivers and reception angle is good, on par
> with accuracy with three receivers (where angle data isn't needed).
> Angle data is what makes the difference.
>
>
> A-GPS depends on reception of GPS signals by the handset, which is a
> problem in many locations (urban canyons, under tree cover, indoors,
> etc.). Because of this serious weakness, hybrid A-GPS systems (e.g.,
> SnapTrack) augment GPS, using Enhanced Cell-ID with CDMA200 that's
> relatively crude as compared to U-TDOA with GSM.
>
>
> All of them. A-GPS requires GPS signals to work. Without such signals,
> accuracy depends on how much the handset has moved since the last
> position fix and on what other location data is available.
>
>
> Enhanced Cell-ID has an accuracy of only 75-500 meters, far less
> accurate than U-TDOA as used in TruePosition U-TDOA.
>
Citation, Zippy?
| |
|
| Dennis Ferguson wrote:
> I do notice we've moved well beyond "doesn't work indoors". Keep
> reading and you'll get up to speed.
LOL, I'm sure that he's been up to speed for a while, and that he fully
understands the advantages of the hybrid system. It's not like all these
European carriers are rushing to implement these systems without knowing
that TDOA systems aren't sufficiently accurate to make a compelling case
for LBS systems.
TDOA was implemented because it was cheap, didn't require new handsets,
and was sufficient to meet the E-911 requirement by the FCC deadline,
period. Cingular knew that in order to sell LBS systems to businesses
that they'd have to deploy a hybrid system eventually, just as they knew
that they'd have to deploy 3G data eventually.
If he really doesn't understand the technology, there are plenty of
resources for him to read.
He can start with
"http://lbs.gpsworld.com/gpslbs/article/articleDetail.jsp?id=308238"
though it gets pretty technical.
| |
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 18:41:00 -0500, Dennis Ferguson
<dcferguson@pacbell.net> wrote in
<slrnf3cvkc.7v.dcferguson@akit-ferguson.com>:
>On 2007-04-30, John Navas < spamfilter1@navasgro
up.com> wrote:
>
>If you say so. Hybrid A-GPS doesn't need the angle to handle the
>two tower case (it can be done just with timing information), only
>the one tower case.
Proof?
>This would imply you've seen non-hybrid A-GPS implemented on some
>cell phone (since that's what you said). Which one?
I'm not at liberty to say.
>
>Proof?
See citation in my prior post.
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 16:43:17 -0700, SMS <scharf.steven@geemail.com>
wrote in < 46367f15$0$27160$742
ec2ed@news.sonic.net>:
>Dennis Ferguson wrote:
>
>
>LOL, I'm sure that he's been up to speed for a while, and that he fully
>understands the advantages of the hybrid system. It's not like all these
>European carriers are rushing to implement these systems without knowing
>that TDOA systems aren't sufficiently accurate to make a compelling case
>for LBS systems.
>
>TDOA was implemented because it was cheap, didn't require new handsets,
>and was sufficient to meet the E-911 requirement by the FCC deadline,
>period. Cingular knew that in order to sell LBS systems to businesses
>that they'd have to deploy a hybrid system eventually, just as they knew
>that they'd have to deploy 3G data eventually.
Proof? Or yet another made up claim?
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| Scott 2007-04-30, 10:33 pm |
| John Navas < spamfilter1@navasgro
up.com> wrote in
news:bovc339njjvg8er
9t53fqaslsmirg6holm@
4ax.com:
> On Mon, 30 Apr 2007 18:41:00 -0500, Dennis Ferguson
> <dcferguson@pacbell.net> wrote in
> <slrnf3cvkc.7v.dcferguson@akit-ferguson.com>:
>
>
>
> I'm not at liberty to say.
Bullshit! You just got caught with your pants down again, Novice.
Translation- you were lying once again. There is no such phone on american
soil, you pinhead.
| |
| Dennis Ferguson 2007-04-30, 10:33 pm |
| On 2007-04-30, John Navas < spamfilter1@navasgro
up.com> wrote:
> On Mon, 30 Apr 2007 18:18:23 -0500, Dennis Ferguson wrote:
>
> What matters, of course, is what's actually in the field, and how well
> it performs in the real world.
Which is exactly what is described in those papers. Let me get
a useful quote out:
Terrestrial Measurements
In addition to the efficient use of GPS signals, strong and
weak, the PDE also makes use of a variety of terrestrial
measurements. Within the CDMA network, these
measurements include coarse and fine pilot phase
measurements from legacy and gpsOneTM enabled
handsets, respectively. The resolution (precision) of
coarse pilot measurements is on the order of 1 CDMA
chip (~240 m), while the resolution of the fine pilot phase
measurements is 1/16 of a CDMA chip (~15 m). On the
reverse link, Round Trip Delay (RTD) measurements are
available for both legacy and gpsOneTM enabled handsets
via the J-STD-036 interface in the control plane
architecture.
>http://www.cdmatech.com/docs_detail...one_hybrid.html>
Got it. You took one line out of a non-technical cartoon presentation
and assumed that is telling you something about how it works.
>
> On the contrary -- A-GPS simply doesn't work without GPS signals (e.g.,
> in urban canyons, under tree cover, _indoors_) -- kindly refrain from
> trying to put words in my mouth.
>
> Hybrid A-GPS systems are a result of scrambling to overcome the serious
> limitations of A-GPS-based positioning alone, which doesn't work well or
> at all in many environments.
Actually, the papers are describing what was deployed 5 years ago. What
positioning technology was Cingular using then?
However, I give up. I think it is pretty clear by now what is factual
and what is being made up.
Dennis Ferguson
| |
|
| Dennis Ferguson wrote:
> However, I give up. I think it is pretty clear by now what is factual
> and what is being made up.
Yet rather than kill-file Navas like most of us, you respond to his
fabrications.
Wait, maybe the accurate system that Cingular doesn't know they have is
somehow related to Extended Range GSM. It only exists in the mind of one
person in the world. Everyone else has to deal with life in the real world.
| |
| Scott 2007-04-30, 10:33 pm |
| SMS <scharf.steven@geemail.com> wrote in
news:46368c77$0$2725
2$742ec2ed@news.sonic.net:
> Dennis Ferguson wrote:
>
>
> Yet rather than kill-file Navas like most of us, you respond to his
> fabrications.
>
And if he didn't, many unsuspecting readers would believe Johhny's
fabrications as truth. There is more damage caused there than the waste of
bandwidth involved in screening his crap. The fact that you respond to his
posts after they have been replied to (as you do in many instances) gives
you little room to criticize others.
Putting your head in the sand like an ostrich is not the solution.
| |
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 19:10:23 -0500, Dennis Ferguson
<dcferguson@pacbell.net> wrote in
<slrnf3d1be.7v.dcferguson@akit-ferguson.com>:
>On 2007-04-30, John Navas < spamfilter1@navasgro
up.com> wrote:
>
>Which is exactly what is described in those papers.
Those papers describe what _can_ be done, not what _has_ been done, or
even what _is_ being done, in the field.
>Got it. You took one line out of a non-technical cartoon presentation
>and assumed that is telling you something about how it works.
No.
>Actually, the papers are describing what was deployed 5 years ago. What
>positioning technology was Cingular using then?
CDMA2000 went for A-GPS, despite its much higher cost and lengthier
deployment, not because it was more accurate (and not because of any LBS
expectations), but because it was the most expedient way, given the
limitations of CDMA2000 gear in the field and in deployment, to comply
with the E911 mandate, albeit with waivers.
GSM similarly went with E-OTD because it was the most expedient way,
given the GSM gear in the field and in deployment, to comply with the
E911 mandate.
In practice both solutions proved to fall short of initial claims, with
GPS signal limitations initially forcing CDMA2000 into a hybrid (kludge)
cell-based approach, and E-OTD limitations forcing GSM into more
sophisticated TruePosition U-TDOA. Development has of course continued
in all areas, blurring the differences.
>However, I give up. I think it is pretty clear by now what is factual
>and what is being made up.
I generally agree, except the real issues here are out-of-control
advocacy and rewriting of history, past, present, and future.
In practice, neither system is really better than the other,
notwithstanding the claims of proponents. They both do a pretty good
job of meeting the E911 mandate, albeit with delays and limitations.
Claiming that one is better than the other is just as silly as claiming
that CDMA2000 is better than GSM, or vice versa, because from the user
perspective, both are capable of very good performance, and differences
in deployment are what matter, not differences in technology.
--
Best regards, FAQ FOR CINGULAR WIRELESS:
John Navas <http://en.wikibooks.org/wiki/ Cingu...less_FA
Q>
| |
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 17:40:22 -0700, SMS <scharf.steven@geemail.com>
wrote in < 46368c77$0$27252$742
ec2ed@news.sonic.net>:
>Dennis Ferguson wrote:
>
>
>Yet rather than kill-file Navas like most of us, you respond to his
>fabrications.
>
>Wait, maybe the accurate system that Cingular doesn't know they have is
>somehow related to Extended Range GSM. It only exists in the mind of one
>person in the world. Everyone else has to deal with life in the real world.
By your pure ad hominems shall we know ye. ;)
--
Best regards,
John Navas <http:/navasgroup.com>
'Those who have evidence will present their evidence,
whereas those who do not have evidence will attack the man.'
| |
|
| Scott wrote:
>
>
> And if he didn't, many unsuspecting readers would believe Johhny's
> fabrications as truth.
There isn't some vast group of readers that automatically believe
anything that these Usenet trolls make up.
Just how many unsuspecting readers out there don't understand that their
exists a group of Usenet posters like Navas whose sole mission in life
is to shill, to be as obnoxious as possible in the process, and to never
provide citations for anything.
> Putting your head in the sand like an ostrich is not the solution.
Ignoring trolls _is_ actually a good solution. Eventually the rolls get
tired of not evoking a response and go away. It worked with Jim, and it
can work with John.
[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.]
| |
| Scott 2007-04-30, 10:33 pm |
| John Navas < spamfilter1@navasgro
up.com> wrote in
news:6t4d335mv42a5nc
lt3u2ov1dglb1pgfmgo@
4ax.com:
>
> By your pure ad hominems shall we know ye. ;)
>
And by your lack of facts and abundance of obvious lies shall we know ye...
| |
| John Navas 2007-04-30, 10:33 pm |
| On Mon, 30 Apr 2007 18:12:03 -0700, SMS <scharf.steven@geemail.com>
wrote in < 463693e4$0$27221$742
ec2ed@news.sonic.net>:
>Just how many unsuspecting readers out there don't understand that their
>exists a group of Usenet posters like Navas whose sole mission in life
>is to shill, to be as obnoxious as possible in the process, and to never
>provide citations for anything.
Pot ... kettle ... black.
In fact I post numerous citations, whereas you post almost none.
--
Best regards,
John Navas <http:/navasgroup.com>
"A little learning is a dangerous thing." [Alexander Pope]
"It is better to sit in silence and appear ignorant,
than to open your mouth and remove all doubt." [Mark Twain]
| |
| Scott 2007-04-30, 10:33 pm |
| SMS <scharf.steven@geemail.com> wrote in news:463693e4$0$2722
1
$742ec2ed@news.sonic.net:
> Scott wrote:
>
>
> There isn't some vast group of readers that automatically believe
> anything that these Usenet trolls make up.
>
> Just how many unsuspecting readers out there don't understand that their
> exists a group of Usenet posters like Navas whose sole mission in life
> is to shill, to be as obnoxious as possible in the process, and to never
> provide citations for anything.
You better check the archives- he's sucked in more than his fair share and
on subjects that could cause heartburn for anyone taking his "advice".
The number of readers is not important- one believing his crap is too many.
>
>
> Ignoring trolls _is_ actually a good solution. Eventually the rolls get
> tired of not evoking a response and go away. It worked with Jim, and it
> can work with John.
>
But you don't ignore him, which was a point I made in the last post that
you conveniently cut out. Again- you have no room to criticize anyone, as
you reply to his posts more often than most here, albeit in response to a
response.
>
> [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.]
>
And give this up- you are the only one crossposting and it makes some
threads unreadable. Obviously, nobody is interested at this time to switch
groups. The time to do this would be when the Cingular name actually
disappears.
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