Antenna Shenanigans
That’s it, I call shenanigans. Ask any electrical engineer about antenna physics and function, and they will tell you Apple is full of it. Two things are very important for antennas – length, and insulation. The length of the antenna is dictated by the wavelength of the signal that you are sending or receiving with that antenna. The antenna should be the 1/4, 1/2 or 5/8 (not common) of the full wavelength. Of course you can have a full wavelength antenna but this is typically too large to be practical. If you use the wrong antenna length, you can get current feedback or signal loss. An antenna that works great at 2.4Ghz will not work as well at 5.8Ghz.
Insulation is also very important. If your antenna is grounded or has a current leak, it results in signal loss and unpredictable behavior. If you connect an antenna to earth ground it becomes essentially useless. The same happens if you connect your antenna to any other part of your device, which is why most antennas on consumer devices have some sort of insulation around them. It’s not just for looks! A Faraday cage takes this to the extreme, grounding out all signals and prevent them from moving or out of the cage.
By touching the bare antenna elements on the iPhone, you are changing the length of the antenna AND causing a current leak between the antennas and the chassis of the phone. The human body is mostly water, so yes, you will attenuate the signal slightly on any phone by holding it. However, touching the elements directly causes a greater effect, and your arm becomes part of the antenna. Of course the effect will vary based on how conductive your body is, which varies by individual and whether your hands are sweaty, oily, etc. This is why some people report problems and some people have no issues. So, basic electrical theory pretty much says Apple is full of it.
Now, instead of trying to fix the problem, Steve Jobs is pulling out the “Hey, this happens to everyone card”. Like I said, any phone will experience *slight* attenuation when you hold it, but not to the degree that some people are experiencing with the iPhone. I have a Blackberry 8830 and Motorola Droid, but neither of them drop so much as a bar regardless of how I hold them. I have no idea how Apple is producing these videos of other cell phones dropping from 5 bars to 0 bars within minutes of holding the phone, but if the effect was that common and pronounced then no one would ever be able to make a phone call while holding their cell phone – and this is obviously not the case.
