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From: ZnU on 10 Aug 2010 02:28
In article <jnp166h3bn92aqnecgr0luki3g48gisuuu(a)4ax.com>,
Jeff Liebermann <jeffl(a)cruzio.com> wrote:

> 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.

The first iPhone was announced in early January 2007 and shipped in
mid-2007.

> 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.

That's not what I'm proposing at all. I'm proposing far more recent
negotiations leading up to the release of the iPad, probably in mid or
late 2009.

I know some people are convinced Apple negotiated some totally rigid
fixed-term multiyear contract back in 2006 or something, but that
doesn't really make sense. I doubt they'd leave themselves that little
flexibility.

We have these various events over the last year:

- AT&T announced one set of iPad plans, and then changed them very soon
thereafter.
- AT&T substantially raised early termination fees for iPhone customers.
- AT&T extended free upgrades to all iPhone customers with upgrade dates
through December 2010
- Android started gaining significant market traction.
- We have persistent rumors of iPhones on Verizon in Q1 2011.

The most parsimonious explanation for all of this is that Apple had the
option of abandoning AT&T exclusivity this year, but negotiated a deal
for another year of exclusivity in exchange for favorable iPad data
plans. Apple then got spooked by Android market share gains, and decided
to ditch AT&T exclusivity in early 2011 rather than mid-2011. As a
consequence, AT&T wasn't willing to offer data plans as generous. AT&T
also raised early termination fees for iPhone users and offered early
upgrades as a way to get as many iPhone users as possible under new two
year contracts that will will be expensive to get out of.

It's speculation, obviously, but it all fits.

> >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.

I also have a 3G iPad and haven't activated service yet; when I'm in my
usual routine, I have WiFi 99% of the time I'd want Internet access on
the iPad. But if I'm going out of town or I'm on-set for a couple of
weeks (we do video production work), _then_ it becomes really useful.
That's why the fact that the plans are month-to-month is so nice.

--
"The game of professional investment is intolerably boring and over-exacting to
anyone who is entirely exempt from the gambling instinct; whilst he who has it
must pay to this propensity the appropriate toll." -- John Maynard Keynes
From: Sandman on 10 Aug 2010 05:29
On 2010-08-10 08:28:06 +0200, ZnU said:

> I also have a 3G iPad and haven't activated service yet; when I'm in my
> usual routine, I have WiFi 99% of the time I'd want Internet access on
> the iPad. But if I'm going out of town or I'm on-set for a couple of
> weeks (we do video production work), _then_ it becomes really useful.
> That's why the fact that the plans are month-to-month is so nice.

I just think your (as in, all you americans, not you specifically)
cellular plans are fucked up. I pay $80/month (VAT included) for
flatrate data and flatrate calls for my plan and twin card that share
the same flatrate data plan is included in the price, and I just went
to my providers home page and clicked "order micro-sim" and it was
posted to me free of charge as my twin card.

Unfortunately, the iPad hasn't been released here yet :( But when it
is, I'll be getting the 3G version (I have imported the wifi version
already) and have free data for it.




--
Sandman[.net]

From: ed on 10 Aug 2010 05:58
On Aug 10, 2:29 am, Sandman <m...(a)sandman.net> wrote:
> On 2010-08-10 08:28:06 +0200, ZnU said:
> > I also have a 3G iPad and haven't activated service yet; when I'm in my
> > usual routine, I have WiFi 99% of the time I'd want Internet access on
> > the iPad. But if I'm going out of town or I'm on-set for a couple of
> > weeks (we do video production work), _then_ it becomes really useful.
> > That's why the fact that the plans are month-to-month is so nice.
>
> I just think your (as in, all you americans, not you specifically)
> cellular plans are fucked up. I pay $80/month (VAT included) for
> flatrate data and flatrate calls for my plan and twin card that share
> the same flatrate data plan is included in the price, and I just went
> to my providers home page and clicked "order micro-sim" and it was
> posted to me free of charge as my twin card.

unlimited (voice, data, txt) plans in the u.s. currently start in the
$45-$50 range. on att, the ipad data plans were $30 unlimited when
they existed ($25 for 2 gigs now); no shared extra-card plans, but
unlimited data plans on other carriers start at about $40 (though i
don't think anyone else has a micro sim at this point). so you're not
really talking about a whole lot of difference in cost when it comes
to the actual plans themselves.

<snip>
From: Sandman on 10 Aug 2010 06:28
On 2010-08-10 11:58:15 +0200, ed said:

>> I just think your (as in, all you americans, not you specifically)
>> cellular plans are fucked up. I pay $80/month (VAT included) for
>> flatrate data and flatrate calls for my plan and twin card that share
>> the same flatrate data plan is included in the price, and I just went
>> to my providers home page and clicked "order micro-sim" and it was
>> posted to me free of charge as my twin card.
>
> unlimited (voice, data, txt) plans in the u.s. currently start in the
> $45-$50 range. on att, the ipad data plans were $30 unlimited when
> they existed ($25 for 2 gigs now); no shared extra-card plans, but
> unlimited data plans on other carriers start at about $40 (though i
> don't think anyone else has a micro sim at this point). so you're not
> really talking about a whole lot of difference in cost when it comes
> to the actual plans themselves.

And those numbers are VAT included and no commitment time? I can get
lower monthly if I commit to a 12/24/48 month plan, but I would never
do that...

VAT in Sweden is 25%. So if your prices are excluded VAT you'd have to
remove 25% from my price to compare (I don't pay VAT since I'm a
business, so...)


--
Sandman[.net]

From: -hh on 10 Aug 2010 07:51
Jeff Liebermann <je...(a)cruzio.com> wrote:
>
>
> 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.

While this all sounds very logical, there's also the possibility that
the right-handed operator dials with his right, then switches hands as
he brings the phone up to his ear. That's what I've been doing with
my Blackberry for years.

As such, a random survey is a far better technique to gather
quantitative data on this use case factor.


> >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.

Agreed that it is good to know/understand why (if not crucial), but
this doesn't address the question of how often it manifests itself as
a problem, via reduced system performance, for the end-item operator
(consumer).


> >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.

There's a strong chronological transition influence on this admittedly
casual sampling. It may be preferable to go look at adoption rates
on the iPhone 3GS, which would be in a far more steady-state condition
by now.


> >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.

There's part of the objective system assessment. If we simplistically
assume a 50% randomness on left-right usage, this would mean that only
50% of operators while in that 10% of remaining coverage would have a
problem - - and by subtraction, roughly 95% of the operator population
won't see the problem.



> >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.

IIRC, from conversations that the two of us have had, you seemed
willing to spot roughly +5dB credit for various factors. Not that the
exact values matter (yet), but observationally, they'll apply to make
that 10% of remaining coverage area effectively smaller.

> 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.

While 'bench' stuff is of course important, to get to TRL 7 or higher,
one eventually has to go outside.

> 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.

Understood: the easy 'bright white line' isn't the expected
condition: its a fuzzy gradient that's invariably going to require
fairly substantial sample sizes to average down the noise/sampling
variances.

> 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.

Every level can have numbers quantitatively put onto it through a well-
designed test. While intermediary values are often quite critical to
Engineering, the bottom line results often "black box" these midpoints
and only care about the macroscopic endpoint. I don't necessarily
like it either, but it is a business reality...and FWIW, we trust this
approach in a lot of areas. For example, while we all agree on the
assertion that 'Smoking Causes Lung Cancer', despite all of the
research done to date, it still is not a deterministic process end-to-
end: its still risk based because of unknown midpoint steps/
processes.


-hh
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