Let me preface this by saying that although I have a Ph.D. in Electrical Engineering, I know very little about electricity. My degree is really in computer systems.
One of the benefits of blogging is that I get to suggest untenable solutions to other people’s problems. Ok, Here goes.
So the issue with the iPhone 4 antenna is that touching with human skin changes it properties. Maybe it changes it frequency response, or maybe you are bridging the two antennas. Not sure.
The crude solution is to add a bumper. Bumper is non-conductive. Problem solved, but not elegantly. So the question is, how else can we protect the antenna from connecting electrically with human skin while still keeping the iPhone beautiful.
Covering with a thin film of some sort of plastic is not an acceptable solution because the plastic woud easily scratch. I don’t think covering with glass would work well either. Too brittle and likely does not expand and contract at the same rate as metal.
You could anodize the metal. Anodizing a metal creates a thin oxide that is not conductive. Alas, you can’t easily anodize steel, because that oxide is called rust and it’s not particularly durable.
Aluminum anodizes well. You can even dye the resulting oxide. My guess is that the outer colorful skins of iPod Nanos are dyed aluminum oxide. But for some reason you don’t see a lot of aluminum antennas out there. Maybe the material does not make a great antenna.
It’s clearly possible to bond stainless steel to aluminum. That is the design of All-Clad cookware, my personal favorite. Their LTD line is stainless steel on the inside, aluminum on the outside. And the aluminum is anodized!
You might have noticed that Apple recently licensed technology related to the creation of alloys. My theory is that this license is related to creating a new external antenna that will have an anodized outer finish.
The other benefit of this solution is that Apple could offer the iPhone in a variety of different antenna colors, as they do the iPod Nano. The solution will be both stylish and functional. How Apple!
Tell me why my idea won’t work in the comments.