Originally Posted by BDBLACK
This is clearly a design flaw...Almost all portable consumer radio products have a plastic coating on their antenna...
EDIT: Notice my section in purple... This could be one of the causes of variability in experience, besides obviously differences in location and the general variability of electromagnetic waves through air, hands, etc.
Originally Posted by solipsism
And the fact that it's not affecting all iPhone 4s doesn't make you think twice about making an arrant claim?
Seriously people, a little objectivity and critical thinking would go a long way here.
Let me try some brain use. I never thought so much about antenna design. But back when I had my "mini compo" there was the 2-3 foot retractable metal antenna. Don't remember how touching it affected it but certainly the positioning did.
As for a TV's metal rabbit ears, yeah, that's hell. Touching it definitely affects the reception, somehow I recall though touching it always *improved* reception, when you did let go, as the poster mention, the TV signal would frustratingly get worse.
Fast forward to the past 10 years, and mobile phones mostly have concealed (AFAIK) antennas and WiFi devices/in laptops all generally concealed.
My 802.11G PCI WiFi card in my PC desktop has a black plastic antenna. I never considered there would be metal inside that plastic, which it probably does.
I had kind of assumed that somehow in the past 10 years they had developed some kind of non- or semi-metallic composite material that acts as a good antenna.
Now, the iPod Touch and iPad has a black plastic part for WiFi and 3G. Clearly in these devices the antenna is covered. The iPad has the WiFi in the Apple logo at the back, covered by the Apple logo plastic, while it has a black part at the top which covers the 3G antenna.
As for the iPhone 3G/S, the metal bezel is the antenna. Now, could this have been causing signal problems due to it being almost fully exposed? That requires better investigation. But globally I don't think it is as big a problem. Sure, touching it could cause poorer reception as some videos have demonstrated but from a global perspective, signal issues seem mainly to occur on ATT.
Now we come to the iPhone 4. Assuming it is held in a "right way" there is still hand-to-metal-antenna contact but the worse signal reduction happens when "bridging" that gap between the two antennas (the "wrong way"). In that sense, you have one antenna that is trying to handle Bluetooth, GPS, WiFi, UMTS and GSM, through a "single" antenna of metal band and human body.
Now here's an interesting test (I knew my Science degree would come in handy one day).Has anybody done any objective testing, for example, in isolating the issue as such - Turn off Bluetooth, GPS (not sure how exactly) and WiFi, and UMTS (3G?) --- how is the GSM-only reception? Is it affected as much? Slowly turn on ONE service at a time, isolating which service may be causing the issue. I haven't looked through the videos but with Bluetooth on could there be worse signal reception? Turn off everything, except for UMTS (not sure how GSM would be force-disabled), are there reception problems?
Another test to do, is to hold, with just two or three fingers, just the sides of the phone. In this way, your hand is again bridging the two antennas. Are there signal problems again? Repeat isolating each service as above. Are your fingers more conductive than your palms? More surface area?
So I would postulate this is the kind of critical thinking that some have been doing, that Apple is definitely doing now.
My theory, and it is obviously not novel, just restating, and highlighting what I believe, is that the problem occurs primarily by the bridging of the antennas, not just "touching any metal antennas"... Because such bridging essentially causes the phone to be one continuous antenna, affected by the human hand, trying to handle 5 different types of signals, across much more spectrum/ channels/ electromagnetic bands. So it's a hardware thing. At the same time, it's a software thing because the software has to figure out, hey, WTF, all these signals, what am I supposed to do?
In conclusion, it appears that a software fix may allow the iPhone4 to understand the variety of signals coming from this one continuous antenna with a lot of interference going on.
In the longer run, Apple's go-to strategy for the next batch of iPhone 4 would be to identify, obtain and integrate into their manufacturing some sort of translucent, thin, electrically-isolating coating for the metal band.
Software the temporary fix, hardware coating the longer-term fix. I'm sure the coating can be obtained, there must be tens or hundreds of companies pitching that to Apple right now. There won't be a redesign of the metal band, any major redesign is impossible at this stage without causing Apple hundred of millions of dollars in cost, R&D, lost sales, delays, lawsuits, etc.