I don't own an iPhone.
It's only with idle curiosity that I follow Apple's wide release this week of the Apple iPhone 4. And it wasn't a day before this whole antenna issue popped up, often and everywhere.
Bottom line, cradling the iPhone 4 in the palm of your left hand, and using the right hand for controls, results in a severe drop in signal often to the point of losing the connection.
Pundits blame the sleek metal band circling the device's outside edge, which Apple admits is part of the antenna system, as are the three gaps in this stainless steel band.
You can see one of these critical antenna gaps in this photo.
And when these gaps are compromised, as when clutched by a sweaty hand, the total antenna pattern is compromised. We all are, after all, just walking, talking, big bags of saltwater.
Whether or not Apple can apply a fix isn't my point. My point is the reason this is a problem goes back to the old concern over the "cell phone radiation".
Most of us remember the time when mobile phones had actual stick-out antennas. Always on top of the device, right? And when pressed up to the ear, that antenna did it's dirty duty and blasted it's output right into our unsuspecting skulls. Bad news.
Well, mobile phone design changed fairly quickly, with the antenna morphing from a whip to a stub to a bump, finally embedded into the body of the device itself. And to keep all that nasty radiation furthest from the head, designers now locate the transmitting antenna in bottom of the device.
But that's also the way we as humans grab and hold the darn thing, so it's unavoidable that our hand contact the antenna, which we shouldn't touch as to not compromise transmission.
This topic isn't new, and antenna design specialists and experts have been pointing out this design conundrum for a while now. One of the saner, studied voices comes from Spencer Webb of AntennaSys, Inc.
Webb has a great technical article posted on his blog, and if you're an early iPhone 4 owner you should check it out.
And don't blame Apple. Don't blame AT&T. Don't blame the FCC. This issue is really the result of them watching out for your own health.
Jim Furrer
In another life, I do analytical work on radio systems. I was almost hired to be a network tester on the iPhone 4 some time back.
ReplyDelete#1, The early cell phones radiated a lot of power and probably had some potential to cause biological heating and damage. The network wasn't very thick so it could be a long trip to the base station. If you had one, you may remember how often you had to recharge the battery because the phone needed so much power to run.
The technology evolved quickly so most people weren't exposed for very long, but the hardcore power users may have had issues.
Today's phones use just a tiny fraction of the power that the old ones did. The network is so thick now that a higher powered phone would prevent the reuse of the same frequencies in a neighboring cell. The power isn't really an issue to humans like it once was, at least on the handset side of the network.
#2, I question the logic in integrating the antenna into the case of the iPhone. Making contact with a live antenna does two things. It increases your exposure to the RF energy, but it also severely attenuates the signal. The impedance match on the antenna goes to crap and the thing just won't work.
I'm not sure how they missed this, but they certainly did (until now.)
The good phones have the antenna hidden somewhere in the back of the phone, where lots of metal electronics are in between the signal and your brain, potentially shielding your skull while radiating the signal out from a clear position.