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iPhone Signal Strength Problems In the UK
An anonymous reader writes "British iPhone users, who bought the Apple phones when they went on sale in England on Nov. 9, are reporting persistent problems with signal strength on O2, the UK's only iPhone service provider. The complaints started only 2 days later. InfoWeek blogger Alex Wolfe says there's a debate as to whether O2 or the iPhone is at fault; it appears to be the handset, which is unusual since US users haven't reported similar problems. Some 02 customers report that getting a replacement phone fixes things; others have had to do a software restore back to version 1.1.2 of the iPhone software."
If it only effects a couple of people, it is not a story.
You would need at least 03 customers before this should make a headline.
You can block Apple stories in your preferences. Or you can ignore them. These are but two of the many bold strategies for avoiding stories you don't like.
" went on sale in England on Nov. 9" Just FYI, the UK isn't just England, it's got Scotland, Wales and Northern Ireland in it too. Hence 'United Kingdom'.
I'm not really sure why you're getting moderated insightful...
Because he was pointing out that anecdotal evidence is worthless.
Ah, but you see, as a people we rely far more on anecdotal evidences than you might think.
If we agree that anecdotal evidences are entirely worthless, what's Amazon, Newegg, Buy.com, etc, etc. doing putting up "Customer Reviews"? What about "Resellerratings"? Or even reports by Better Business Bureau, or Consumerist, or Consumer reports? Unless it's a designed-to-be-fair poll (which almost all online polls aren't) of statistically significant numbers (I usually go with 1000, because that gives nice 3% margin of error, assuming no other sources (such as sampling bias, wrong question wording, etc.) than random sampling error), it's little better than anecdotal evidences---a couple people lying, a company astroturfing will be enough to skew the results way over to the other side.
But, such quality results are hard to come by (I daresay even in clinical studies, let alone psychology survey, such quality is hard to obtain), so if you've ever listened to anyone you don't know personally (and somehow can trust his/her expertise), you have let an anecdotal evidence influence your judgment. Does that mean you are stupid? Well, not any more than me, the president (of U.S., of Canada, prime minister of U.K., anybody important, really), or the vast majority of rational population.
In fact, anyone dismissing an anecdotal evidence just because it's an anecdotal evidence (rather than, say, it can be shown to be false experimentally, or there is some logical fallacy) is simply repeating the folly of Descartes (of overt doubt). Except of course, unlike Descartes, he has absolutely no originality and a hindsight of several centuries, which should prevent all but utter fools from falling into such mistake.
It is probably caused by some combination of these two things:
1. Transmit power for 1800/1900 (probably what is in use in NZ) is half the wattage allowed for the 850 band in the U.S. The 850 MHz allows for significantly greater tower spacing at a cost in cell phone life. You can't get away with that in the 1900 MHz band because the signal doesn't carry as well. AT&T uses 850 heavily, for obvious reasons, though in California, you will likely find many 850 MHz towers at much closer spacing and at reduced power to minimize the cell's overall coverage footprint to reduce the collisions inherent in high density environments with limited spectrum. You shouldn't see your cell shouting at anywhere near maximum output, though, so I sort of doubt this has that much to do with the difference, though I suppose it might be a factor.
2. GSM phones can use different encodings depending on signal strength, available bandwidth, the preference of the tower, and the intersection of modes supported by both your phone and the tower. It is much more likely that the phone is operating in one of the lower power modes in NZ. Half rate codec draws significantly less power than the other codecs, and EFR draws slightly more. IIRC, in California, AT&T's towers prefer FR if the phone supports it, because the call quality sounds better and they have enough tower density to handle it. In NZ, they may be using HR, which by itself can make a huge difference in talk time because the cell phone is essentially "talking" to the tower during only half as many time slots.
Check out my sci-fi/humor trilogy at PatriotsBooks.
While metal is shiny and slick, when it is too close to an antenna, the bandwidth decreases. So the antenna designer has a choice of which frequencies to focus their design effort. Since their initial target market was the USA, they probably targeted GSM850 (AT&T's GSM network). From the antenna photos, the GSM 1800/1900 part of the antenna is the part closest to the battery/metal covers, which further degrades performance in this band. One of the earlier replies said their iPhone worked fine in the country-side of the UK. This is most likely due to the GSM850/900 part of the antenna being furthest away from the battery/metal covers.
iPhone disassembled:
http://www.ifixit.com/Guide/iPhone/Communications-Board/105/8/Page-7/Communications-Board
One can see a small little cable going from the RF Module to the antenna. In almost 99% of the GSM phones on the market today, the antenna is right next to the RF Module. This is to minimize the RF losses between the RFIC and the antenna. By using a cable, significant losses are introduced into the system by both the cable and the miss-match at both ends of the cable. The antenna is also at the bottom of the phone and is more likely to be covered by the user's hand (further decreasing sensitivity); though there are quite a few phone on the market with antennas at the bottom--it is how they get around the SAR limits which are specified as the peak radiation a user receives next to their ear (the mouth area is not measured in the FCC/EU tests.
So, while from an anecdotal perspective, it appears the iPhone has random sensitivity issues; from an antenna engineer's perspective however, it is no surprise why the iPhone has lower performance than most phones (but would still have similar performance to other phones with poor antenna designs--of which there are several for different reasons than cable losses).
If you are interested in reading more technical reports about antenna performance in mobile phones, go to the following website:
http://antennas.astri.org/antennas_mirror
PDF Password = astriantennas