In article <[email protected]>, Larry
<[email protected]> wrote:

> > go try a sirf star iii chipset sometime. it works great indoors, even
> > inside a steel frame building. we've gone over this before and i
> > posted links.
> >
> The Nokia pucks ARE SirfStar III Chipsets.

then it should work indoors. either that or you're doing something
wrong.

> That doesn't bypass the laws of PHYSICS, just for hype.

doesn't need to.

> You may be looking at position smoothing on that device, averaging out
> the actual position fixes every second to prevent it from hopping. They
> do a lot of trickery with this Agps bull****.

nope. it was on a garmin hiking gps that had no assistance whatsoever,
and it was inside a steel frame department store. it picked up like 6
satellites, while standing at the counter, while the non-sirf star
model next to it picked up none.

In article <[email protected]>, Larry
<[email protected]> wrote:

> > it doesn't with the better gps chipsets.
>
> Horse****.

go try a sirf star iii chipset sometime. it works great indoors, even
inside a steel frame building. we've gone over this before and i posted
links.

In article <[email protected]>, SMS
<[email protected]> wrote:

> As long as "assisted GPS means what it's supposed to mean. Some people
> were referring to the orginal E-911 service used by GSM carriers as
> "assisted GPS," when it was solely triangulation and there was no GPS at
> all.

then they're mistaken.

> All the complaints about the iPhone GPS accuracy are related to the
> assisted GPS system it uses.

not really. it's mostly due to unrealistic expectations.

> If it can't see the satellites then it
> triangulates from WiFi and cellular towers and the position is not very
> accurate. People are used to portable GPS systems that are extremely
> accurate once they get a view of the satellites, and don't work at all
> until they can see enough satellites.

true, but that's not a bad thing. a regular gps would just sit there
with a blank screen while trying to get a fix (especially if it hasn't
been used for a few days), whereas the iphone is ready to go almost
immediately and updates itself as it picks up more satellites.

> They expect the iPhone to be just
> as accurate. Might be nice if you could turn the "assisted" part off and
> just wait for a satellite fix.

you in effect can. apps can request a certain level of accuracy and
decide what to do if can't meet that, such as display an alert. one gps
app displays a red banner at the top that says the gps signal is weak
until it gets a fix that is accurate enough for navigation, however, it
almost always manages to show the car on the correct road even when
it's weak.

On 14/06/10 11:37 AM, Dennis Ferguson wrote:

> I've noticed that. While this might say something about Apple's antenna
> design skills, or about Infineon's hardware (the iPad seems to have replaced
> it), or Broadcomm's navigation software, or the RF environment inside a
> cell phone in general, it has nothing at all to do with Assisted GPS. Even
> the most precise autonomous unit can benefit from assistance data when that
> is available, even if it can run without it.

As long as "assisted GPS means what it's supposed to mean. Some people
were referring to the orginal E-911 service used by GSM carriers as
"assisted GPS," when it was solely triangulation and there was no GPS at
all.

All the complaints about the iPhone GPS accuracy are related to the
assisted GPS system it uses. If it can't see the satellites then it
triangulates from WiFi and cellular towers and the position is not very
accurate. People are used to portable GPS systems that are extremely
accurate once they get a view of the satellites, and don't work at all
until they can see enough satellites. They expect the iPhone to be just
as accurate. Might be nice if you could turn the "assisted" part off and
just wait for a satellite fix.

Whether the iPhone's GPS issues are due to antenna design, the amplifier
and GPS chip, or users simply not realizing that a GPS needs to have a
clear view of the satellites, which takes time and nothing in the way,
is unknown, but I'd wager that it's the latter.

In article <[email protected]>, Dennis
Ferguson <[email protected]> wrote:

> > The inaccuracy of the iPhone GPS can easily be demonstrated by comparing
> > reported positions to actual positions. I've often seen errors of
> > hundreds of feet, making it unusable for critical marine navigation.
>
> I've noticed that.

i haven't.

it starts off coarse and then gets more accurate, just like other gps
devices. the other night, the maps app had the dot approximately where
i was in the house, in from the road. at most, it was about 10 feet
off, and that was *inside* the house.

on the other hand, the driving apps have crappy snap-to-road
algorithms. if you're on a parallel frontage road, it sometimes gets it
wrong. i've seen that on garmin gps devices too but not as often.

> While this might say something about Apple's antenna
> design skills, or about Infineon's hardware (the iPad seems to have replaced
> it), or Broadcomm's navigation software, or the RF environment inside a
> cell phone in general, it has nothing at all to do with Assisted GPS. Even
> the most precise autonomous unit can benefit from assistance data when that
> is available, even if it can run without it.

true. it has to do with how many gps satellites it can see.

On 2010-06-14, John Navas <[email protected]> wrote:
> On Mon, 14 Jun 2010 13:08:36 -0500, in
><[email protected]>, Dennis Ferguson
><[email protected]> wrote:
>
>>On 2010-06-14, SMS <[email protected]> wrote:
>
>>> Assisted GPS is much less accurate and depends on connectivity to the
>>> network. However it can be faster, at least at start-up. You would not
>>
>>That isn't true in general. Assisted GPS can mean many things, you need
>>to read the data sheet for the hardware to find out what it actually does.
>>
>>The product brief for the GPS receiver Apple uses (the Infineon version,
>>at least, I think the iPad has a Broadcomm-labeled version instead) says
>>this
>>
>> Multiple-mode operation
>> – Ms-based (calculation of position in mobile handset)
>> – Ms-assisted (calculation of position in base station)
>> – Autonomous (no assistance by network)
>> – Enhanced autonomous (using four day assistance data)
>>
>>which seems like it has all bases covered. There's no reason at all to
>>think that would be "less accurate" either.
>>
>>The reason you only get GPS with 3G seems to be that the particular
>>GPS hardware Apple has used to date is a peripheral chip for the Infineon
>>baseband unit. The control software runs in the baseband unit, and
>>the GPS chip leaches off the baseband chip's clock, so if there isn't
>>a 3G baseband chip in the system there's nothing to solder the GPS
>>unit to.
>
> The inaccuracy of the iPhone GPS can easily be demonstrated by comparing
> reported positions to actual positions. I've often seen errors of
> hundreds of feet, making it unusable for critical marine navigation.

I've noticed that. While this might say something about Apple's antenna
design skills, or about Infineon's hardware (the iPad seems to have replaced
it), or Broadcomm's navigation software, or the RF environment inside a
cell phone in general, it has nothing at all to do with Assisted GPS. Even
the most precise autonomous unit can benefit from assistance data when that
is available, even if it can run without it.

Dennis Ferguson

In article <[email protected]>, John Navas
<[email protected]> wrote:

> >> >Well, to be fair, the GPS is only included with the iPad 3G, ...
> >>
> >> That's because it's (cheaper) A-GPS (Assisted GPS),
> >> which isn't as accurate as (mor expensive) standalone GPS.
> >
> >The GPS chips in the iPad 3G and other GSM devices are "real" standalone
> >satellite GPS and do not require a cellular connectivity. The reason
> >it's only included in the 3G model is because the GPS chip is integrated
> >in the 3G chipset, much like most GSM phones with internal GPS.
>
> It's A-GPS:

which is as he said, a real gps, but assisted. maybe you should read
the links you cite.

In article <[email protected]>, John Navas
<[email protected]> wrote:

> The inaccuracy of the iPhone GPS can easily be demonstrated by comparing
> reported positions to actual positions. I've often seen errors of
> hundreds of feet, making it unusable for critical marine navigation.

i've seen errors of hundreds of feet with various gps devices,
including garmin and tomtom. it all depends on how many satellites it
sees. it's not a flaw with the iphone, despite your repeated bashing.

On Mon, 14 Jun 2010 13:05:16 -0400, in
<[email protected]>, Todd Allcock
<[email protected]> wrote:

>At 14 Jun 2010 07:15:05 -0700 John Navas wrote:
>
>> >Well, to be fair, the GPS is only included with the iPad 3G, ...
>>
>> That's because it's (cheaper) A-GPS (Assisted GPS),
>> which isn't as accurate as (mor expensive) standalone GPS.
>
>The GPS chips in the iPad 3G and other GSM devices are "real" standalone
>satellite GPS and do not require a cellular connectivity. The reason
>it's only included in the 3G model is because the GPS chip is integrated
>in the 3G chipset, much like most GSM phones with internal GPS.

It's A-GPS:
<http://artoftheiphone.com/2008/06/10/iphone-3g-what-is-assisted-gps/>
<http://gizmodo.com/5015930/giz-explains-what-you-didnt-know-about-the-iphone-3gs-gps>

--
Best regards,
John

"Assumption is the mother of all screw ups."
[Wethern’s Law of Suspended Judgement]

In article <[email protected]>, SMS
<[email protected]> wrote:

> Assisted GPS is much less accurate and depends on connectivity to the
> network.

nope. assisted gps means it can get a fix faster. after that, it's
exactly the same as any other gps.

> However it can be faster, at least at start-up.

right, that's the whole point.

> You would not
> want to depend on it for road trips that happen to leave an urban area
> that's for sure, but you never know what some people will do.

of course you would. it works just fine.

> I recall
> pointing out to someone once that one of the less major, but still well
> used, routes through the Sierra Nevada (CA 88) had only CDMA and AMPS
> cellular coverage and they explained that they were aware of this and
> that they planned their travels to avoid roads that lacked cellular
> coverage for Cingular.

which has nothing to do with gps.

In article <[email protected]>, SMS
<[email protected]> wrote:

> I'd much rather have just the external antenna left in the car than the
> whole USB puck. That's how the old CF GPS for my PDA worked. When you
> were outside, the internal antenna worked fine, when you were inside the
> steel car, and you had your PDA sitting in a cradle in front of the
> dash, you plugged in the antenna.

that would be nice but not enough people find it to be a limitation. i
think it's tomtom who makes a gps cradle which has its own gps that
talks to its app (which is a piece of **** but that's another story).

On Mon, 14 Jun 2010 13:08:36 -0500, in
<[email protected]>, Dennis Ferguson
<[email protected]> wrote:

>On 2010-06-14, SMS <[email protected]> wrote:

>> Assisted GPS is much less accurate and depends on connectivity to the
>> network. However it can be faster, at least at start-up. You would not
>
>That isn't true in general. Assisted GPS can mean many things, you need
>to read the data sheet for the hardware to find out what it actually does.
>
>The product brief for the GPS receiver Apple uses (the Infineon version,
>at least, I think the iPad has a Broadcomm-labeled version instead) says
>this
>
> Multiple-mode operation
> – Ms-based (calculation of position in mobile handset)
> – Ms-assisted (calculation of position in base station)
> – Autonomous (no assistance by network)
> – Enhanced autonomous (using four day assistance data)
>
>which seems like it has all bases covered. There's no reason at all to
>think that would be "less accurate" either.
>
>The reason you only get GPS with 3G seems to be that the particular
>GPS hardware Apple has used to date is a peripheral chip for the Infineon
>baseband unit. The control software runs in the baseband unit, and
>the GPS chip leaches off the baseband chip's clock, so if there isn't
>a 3G baseband chip in the system there's nothing to solder the GPS
>unit to.

The inaccuracy of the iPhone GPS can easily be demonstrated by comparing
reported positions to actual positions. I've often seen errors of
hundreds of feet, making it unusable for critical marine navigation.

--
Best regards,
John

If the iPhone and iPad are really so impressive,
then why do iFans keep making excuses for them?

On 2010-06-14, SMS <[email protected]> wrote:
> On 14/06/10 8:59 AM, DevilsPGD wrote:
>> In message<140620101139259894%[email protected]> nospam
>> <[email protected]> was claimed to have wrote:
>>
>>> In article<[email protected]>, John Navas
>>> <[email protected]> wrote:
>>>
>>>> That's because it's (cheaper) A-GPS (Assisted GPS),
>>>> which isn't as accurate as (mor expensive) standalone GPS.
>>>
>>> absolute nonsense. assisted gps gets a fix faster and just as accurate.
>>
>> Faster, absolutely, IF internet connectivity is available.
>>
>> It's only "just as accurate" if you happen to be in an area with a
>> reasonable number of wifi access points.
>>
>> However, if the only wifi access point in range is the Airport Express
>> you carry with you for use in wired-only hotels, you'll get a previous
>> location that Airport Express was seen (possibly a different country)
>
> Assisted GPS is much less accurate and depends on connectivity to the
> network. However it can be faster, at least at start-up. You would not

That isn't true in general. Assisted GPS can mean many things, you need
to read the data sheet for the hardware to find out what it actually does.

The product brief for the GPS receiver Apple uses (the Infineon version,
at least, I think the iPad has a Broadcomm-labeled version instead) says
this

Multiple-mode operation
– Ms-based (calculation of position in mobile handset)
– Ms-assisted (calculation of position in base station)
– Autonomous (no assistance by network)
– Enhanced autonomous (using four day assistance data)

which seems like it has all bases covered. There's no reason at all to
think that would be "less accurate" either.

The reason you only get GPS with 3G seems to be that the particular
GPS hardware Apple has used to date is a peripheral chip for the Infineon
baseband unit. The control software runs in the baseband unit, and
the GPS chip leaches off the baseband chip's clock, so if there isn't
a 3G baseband chip in the system there's nothing to solder the GPS
unit to.

Dennis Ferguson

On 14/06/10 8:59 AM, DevilsPGD wrote:
> In message<140620101139259894%[email protected]> nospam
> <[email protected]> was claimed to have wrote:
>
>> In article<[email protected]>, John Navas
>> <[email protected]> wrote:
>>
>>> That's because it's (cheaper) A-GPS (Assisted GPS),
>>> which isn't as accurate as (mor expensive) standalone GPS.
>>
>> absolute nonsense. assisted gps gets a fix faster and just as accurate.
>
> Faster, absolutely, IF internet connectivity is available.
>
> It's only "just as accurate" if you happen to be in an area with a
> reasonable number of wifi access points.
>
> However, if the only wifi access point in range is the Airport Express
> you carry with you for use in wired-only hotels, you'll get a previous
> location that Airport Express was seen (possibly a different country)

Assisted GPS is much less accurate and depends on connectivity to the
network. However it can be faster, at least at start-up. You would not
want to depend on it for road trips that happen to leave an urban area
that's for sure, but you never know what some people will do. I recall
pointing out to someone once that one of the less major, but still well
used, routes through the Sierra Nevada (CA 88) had only CDMA and AMPS
cellular coverage and they explained that they were aware of this and
that they planned their travels to avoid roads that lacked cellular
coverage for Cingular.

On 14/06/10 8:42 AM, nospam wrote:
> In article<[email protected]>, Larry
> <[email protected]> wrote:
>
>> My puck stays in the car, plugged into a cig lighter USB charger when the
>> car is running. I think I took it out to show a guy with an iPhone and no
>> GPS about a year ago. There's a cover on my dash and the puck is under it
>> to keep it out of the sun. The heat doesn't seem to bother it.
>
> which means it won't work outside of the car. that's a huge drawback.
>
>> Why would you carry it, unless you're going for a walk in a strange city?
>
> location aware software.

I'd much rather have just the external antenna left in the car than the
whole USB puck. That's how the old CF GPS for my PDA worked. When you
were outside, the internal antenna worked fine, when you were inside the
steel car, and you had your PDA sitting in a cradle in front of the
dash, you plugged in the antenna.

What you're seeing with all these after-market vehicle GPS systems is
that you have to have them on the dash (or mounted to the windshield).
In California, they finally passed a law permitting the GPS to be
attached to the windshield (effective January 2009) but it's still
illegal to place it front and center (which is where most people place
it). You can get a fine for "obstructed windshield" but I don't think
it's enforced much. Unfortunately, only CA and NJ have these laws, so
most of the GPS makers dropped their external antenna ports knowing that
most people will ignore the rather than start messing with antennas.

When I used to use the Motorola Professional Hands Free Car Kits, they
mounted in a very good location with the bracket usually just to the
right of the radio. When you put your phone into the hang-up cup it
connected the speakerphone and an external antenna. I liked not having
cords running everywhere for charging and speakers. The external antenna
greatly boosted the range of the phone.