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From: nospam on 10 Aug 2010 01:30
In article <znu-2B1F5F.00241810082010(a)Port80.Individual.NET>, ZnU
<znu(a)fake.invalid> wrote:

> > i'm sure apple will be happy to include sprint and t-mobile users
> > too, as well as sprint and t-mobile will be happy to carry it.
> > there's little point in doing verizon and not doing sprint (same
> > radio).
>
> The issue there is that that Sprint is going with WiMax for 4G while
> everyone else is going with LTE. It would probably annoy people if Apple
> supported Sprint now but stopped in a year or two.

sprint has said they can easily switch to lte if need be. it's all
software. however, having a wimax iphone on sprint would be welcomed
too. either way, cdma is going to be dominant for a *while*. verizon
said they expect to cover 75% with lte in 2-3 years, so it will have to
be a hybrid to be useful.

> > > Will Verizon's data network crumble under the crush of iPhone data
> > > like AT&T's did?
> >
> > it's handling android just fine, and by some reports, android users
> > use *more* data than iphone users.
> >
> > what will be very interesting is how many at&t customers switch away
> > from at&t once the iphone goes multi-carrier.
>
> I probably will. I'm passing on an iPhone 4 upgrade specifically to
> avoid having to extend my contract.
>
> I think AT&T's statement that they don't expect much of a hit from this
> is exceedingly optimistic.

obviously. what are they going to say? yea we know we're going to
hemorrhage customers?

> I admit my social circle is probably not
> exactly representative, but literally more than half the people I know
> 1) have iPhones, 2) switched to AT&T specifically to get iPhones, and 3)
> love their iPhones but aren't especially happy with AT&T.

at&t is the #1 complaint in every survey i've seen.
From: nospam on 10 Aug 2010 01:31
In article <znu-C9C9BC.01290410082010(a)Port80.Individual.NET>, ZnU
<znu(a)fake.invalid> wrote:

> > and let's not forget, at&t offered *unlimited* ipad data plans, only to
> > backtrack on that, so if they actually did cut a deal based on that,
> > at&t basically voided it by their bait&switch tactics.
>
> Or perhaps the unlimited plans were negotiated for a 12 month extension
> on iPhone exclusivity, but Apple decided to renegotiate for a 6 month
> deal and had to settle for worse iPad plans. The timing would be about
> right with respect to when Android started picking up momentum.

that's also a possibility.
From: Jeff Liebermann on 10 Aug 2010 01:38
On Tue, 10 Aug 2010 00:41:24 -0400, ZnU <znu(a)fake.invalid> wrote:

>In article <itg1661nn11cl9jg5r66hjnm915f6tm6hd(a)4ax.com>,
> Jeff Liebermann <jeffl(a)cruzio.com> wrote:
>
>> On Mon, 09 Aug 2010 23:00:16 -0400, ZnU <znu(a)fake.invalid> wrote:
>>
>> <http://www.engadget.com/2010/07/13/yes-the-iphone-4-is-broken-no-the-iphone-4
>> -is-not-broken/>
>>
>> >The issue was real-world performance; the Engadget reports are more
>> >relevant.
>>
>> Please excuse my amusement. It's usually someone complaining that
>> something doesn't work, where my test data shows that everything is
>> just fine. This is literally the first time it's been the other way
>> around. My test data shows it's broken, but nobody seems to be
>> complaining. Am I living in a mirror universe?
>
>My guess would be that your testing procedures are not fully
>representative of real-world use in this instance and/or real-world
>cellular performance is influenced by so many factors that whatever
>difference you're measuring gets lost in the noise. See below.

I'm not sure how you got from my amusement over the reversal of the
traditional roles, but I'll be happy to answer your questions about my
procedures. However, one suggestion: Please find another name for
empirical and anecdotal user experience data. It's not my idea of
"real world". Mine has numbers attached.

>Apple has been doing this in its support forums forever.

I didn't know this. That was my first posting to the Apple support
forum. Frankly I'm disappointed and mildly disgusted.

>OK. Now:

Ok, we'll just ignore the one solitary report that demonstrates a data
slowdown with the death grip.

>1) How often are people really using the "death grip"?

90%. It's fairly difficult to hold the phone in the left hand without
touching the antenna gap. Some Googling showed that 7-10% of the
population is left handed. In order to dial the phone, a right handed
person holds the phone in the left hand, and dials with the right.
Therefore, right handed people tend to talk with the phone in their
left hand. They may change later for one reason or other, but they
start holding the phone in their left hand.

>2) How much worse is this than other phones?

12.5 to 39.6 times worse. See my web page at:
<http://802.11junk.com/jeffl/cellular/cell-test.htm>
Most cell phones have about a -9dB (8x) reduction in signal strength
when the antenna is covered by the hand. That includes phones with
telescoping antennas. The iPhone has a -20dB (100x) to -25dB (316x)
reduction in signal strength. That's somewhere between 12.5 and 39.5
times worse for the iPhone 4.

This difference in how the iPhone performs is what my web page was
intended to highlight. The question is *NOT* whether a -25dB drop is
detrimental, since various users have demonstrated that in apparently
strong signal areas, it works just fine. The question is *WHY* is
there such a large drop in signal strength? It's certainly not
typical or normal and is far more severe than could be explained by
construction or mechanical differences.

>3) What fraction of people use cases/bumpers and would have regardless
> of whether this issue existed or not?

Very few. I don't have access to sales figures on rubber bumpers, but
my guess is that everyone buys one or gets one for free, but doesn't
use one. I think I've seen about 15 assorted iPhone 4's so far. Three
of them had rubber bumpers. A week later, only one did. The rubber
bumper feels odd, looks awful after they get dirty, are ugly, and most
important, are a visible admission that there's something wrong with
the phone.

>4) Does signal strength have to be within a specific range to produce
> the issue?

Yes. The dynamic range of the phone is approximately -110dBm to maybe
about -40dBm (based upon a quick check of some typical front end
chips). That's 70dB of dynamic range. With a -24dB loss in signal
caused by hand contact, the signal will hit bottom with:
-110dBm - -24dB = -86dBm
or less input. My guess(tm) is that the phone needs about 15dB
overhead to maintain a connection, making the minimum signal where
there's no effect at:
-86dBm + 15dB = -71dBm
Anything under -71dBm will show some hand effects. Anything over
-71dB will not have a problem. If you look at my web page, you'll
notice that -71dBm is well above the typical signal strength shown by
a typical conventional cell phone.

>If so, what fraction of call activity takes place in
> locations with those conditions?

See above. My office is not exactly a strong signal area and shows
signal strengths in the -80dBm area. An iPhone 4 in that area would
probably show some tendency to disconnect if in a death grip and while
moving around (walking through holes). If I went outside, where the
signal is stronger, probably no effect.

In the distant past, I did some modeling of a typical cell site
coverage.
<http://802.11junk.com/cellular/jeffl/SVLY-PGE/index.html>
<http://802.11junk.com/cellular/>
This is for a 3 panel Sprint installation on a local PG&E tower. I
ran some spot checks in the area around the tower and found the signal
strengths to be reasonably sane, but not very accurate because the
power per channel varies with the reported SNR from the handset.
Anyway, looking at the coverage area, -70dBm covers about 90% of the
expected coverage area. The suggests that the iPhone 4 will not have
a problem in 90% of the expected coverage area for this cell site.

>5) Are there different conditions under which the iPhone 4's antenna
> design performs _better_ than other designs?

Yes. The iPhone 4 antenna is much longer and larger than most
antennas. Even the common 1/4 wave whip antenna is smaller. The odd
shape will reduce the iPhone 4 antenna's effectiveness somewhat. I
also have my doubts if it's properly matched. Still, bigger is
better.

If you look at my table of signal strengths, the "two finger" signal
strength column is essentially a signal strength test (for the first 7
VZW phones only). These were tested in my palatial office, in a very
stable and fixed location. The relative signal levels indicates how
well the phone is hearing the cell site. The phones with the external
telescoping antenna is easily 6dB better than those with projecting
radome antennas, and about 9dB better than internal antennas.

>You can't get from measured signal strength (or measured bandwidth) to
>real-world performance without knowing the answers to these questions.
>Which as far as I know, nobody does.

Three problems.

I don't have any interest in "real world", whatever that means. If it
doesn't work on the bench, it's going to have some manner of problem
in the field. I don't know exactly how prevalent this problem will
be, or exactly how it will manifest itself. That which you don't
understand, will turn around and bite.

The 2nd problem is that there really is a direct relationship between
measurement and field performance. You may not see it directly
because cell phones are designed to act the same in strong and weak
signal areas, but it's there. All you have to do is look for it. It
won't be difficult to find a condition where you'll have a spectacular
loss in signal, just as it's possible to find a condition where
nothing happens.

I don't see any connection between whether the phone has a problem and
your questions. They all deal with the perception of the problem, not
the actual problem. If I put on my marketing hat, I will have some
interest in such perceptions. While I have my engineering hat on,
it's numbers and nothing else.

--
Jeff Liebermann jeffl(a)cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
From: Jeff Liebermann on 10 Aug 2010 01:54
On Tue, 10 Aug 2010 01:00:25 -0400, ZnU <znu(a)fake.invalid> wrote:

>In article <d3l166pv78e06dtkos55ep7itgp821dem2(a)4ax.com>,
> Jeff Liebermann <jeffl(a)cruzio.com> wrote:
>
>> On Tue, 10 Aug 2010 00:16:25 -0400, ZnU <znu(a)fake.invalid> wrote:
>
>[snip]
>
>> >I suspect Apple is done making any deals that would allow exclusivity to
>> >continue longer. They couldn't possibly get enough money out of AT&T to
>> >offset both the lost sales and the long-term consequences of allowing
>> >their competitors to gain considerable market share solely because their
>> >devices are on more carriers. Plus, Apple appears to have been following
>> >a very deliberate strategy of moving away from exclusive deals in
>> >various markets -- I think the US and Germany are the only markets left
>> >where the iPhone is only one one carrier.
>>
>> Agreed. I don't really understand why Apple would trade low cost data
>> service for an exclusive. There's plenty of revenue loss to Apple by
>> not being able to sell to other providers, but there's no revenue in
>> low cost data service for Apple.
>
>The iPad is a device on which cellular data is a very compelling
>feature, but it's primarily targeted at consumers and there's no way
>most consumers were going to pay $60/month for a data plan (which seems
>to be the going rate).

The first iPhone was announced in mid 2008. Presumably, the design
and AT&T negotiations started about 2 years prior, in 2006.
The iPad was released in mid 2010, with development perhaps starting
in about 2008. In 2006 or 2007, when Apple and AT&T were probably
negotiating the contract, the iPad was probably just a concept. I
don't think that Apple would have found any need or reason to disclose
future projects to AT&T this far in advance. My guess(tm) is that the
iPad and iPhone contracts were negotiated seperately.

>So the availability of data plans that regular consumers might actually
>be willing to pay for makes the iPad itself more attractive and
>presumably helps sell more of them.

Apple covered its posterior by making a Wi-Fi only version. The sales
breakdown between the two models might offer a clue as to how
important this data plan was to consumers. I only know 4 iPad owners.
All of them have the more expensive version with the 3G data modem.
However, only one subscribes to the AT&T data plan and she bought the
$15 cheapo version. I've asked about the logic behind paying for
something they're not using and get something about "playing it safe"
and the internal GPS.



--
Jeff Liebermann jeffl(a)cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
From: nospam on 10 Aug 2010 02:07
In article <jnp166h3bn92aqnecgr0luki3g48gisuuu(a)4ax.com>, Jeff
Liebermann <jeffl(a)cruzio.com> wrote:

> >The iPad is a device on which cellular data is a very compelling
> >feature, but it's primarily targeted at consumers and there's no way
> >most consumers were going to pay $60/month for a data plan (which seems
> >to be the going rate).
>
> The first iPhone was announced in mid 2008.

nope. it was announced january, 2007 and shipped in june, 2007.

> Presumably, the design
> and AT&T negotiations started about 2 years prior, in 2006.

at the announcement in january, 2007, steve jobs said that it was a day
he had been looking forward to for 2.5 years.

> The iPad was released in mid 2010, with development perhaps starting
> in about 2008.

the ipad was announced in january, 2010, and shipped in april 2010.

> In 2006 or 2007, when Apple and AT&T were probably
> negotiating the contract, the iPad was probably just a concept.

actually, the ipad dates back to the early 2000s (aka the 'safaripad').
apple decided to do a phone first, then go back to the tablet.

> I don't think that Apple would have found any need or reason to disclose
> future projects to AT&T this far in advance. My guess(tm) is that the
> iPad and iPhone contracts were negotiated seperately.

at&t probably did not know of the ipad until late in the game, as apple
is very secretive about projects. however, at some point, they
negotiated the 'unlimited' plan that was quickly cancelled.

> >So the availability of data plans that regular consumers might actually
> >be willing to pay for makes the iPad itself more attractive and
> >presumably helps sell more of them.
>
> Apple covered its posterior by making a Wi-Fi only version. The sales
> breakdown between the two models might offer a clue as to how
> important this data plan was to consumers. I only know 4 iPad owners.
> All of them have the more expensive version with the 3G data modem.
> However, only one subscribes to the AT&T data plan and she bought the
> $15 cheapo version. I've asked about the logic behind paying for
> something they're not using and get something about "playing it safe"
> and the internal GPS.

the gps is extremely useful, and having a 'just in case' 3g pay as you
go data capability is very compelling. the wifi-only version likely
exists only to hit a price point, or for those who plan on using the
ipad only at home or office where there is always wifi.
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