When the rumored Apple iPhone 4 was leaked by Gizmodo before its official release, many people were skeptical of its authenticity. One of the big issues with the leaked phone was it had several gaps in the stainless steel band surrounding it, which is not characteristic of Apple’s streamline design. Here is a photo showing the positions of the three gaps and the steel housing:

iPhone 4 gaps along the steel band surrounding the phone

However, the leaked prototype was indeed authentic as revealed by Apple CEO Steve Jobs on Monday (June 9th, 2010). In his speech, Jobs talked about all the brilliant engineering that went into the iPhone 4 and how revolutionary it is. In particular, he discussed the three gaps in the steel band along the case of the iPhone and said these gaps were part of the iPhone 4’s novel antenna design; one part is dedicated to Bluetooth, WiFi, and GPS and the other larger half to UMTS and GSM. Here is a slide showing the steel band breakdown:

According to Jobs, such an antenna design has never been done before in a phone and that it will help reduce dropped calls/connections which plague the AT&T network. However, the phone had wireless connectivity problems during Job’s presentation. At one point, he asked everyone in the audience to shutdown any mobile hotspot units. So until the phone is released on June 24th, 2010, we won’t know if the novel antenna design has any benefit. We do know that the FCC confirms that the iPhone 4’s highest SAR is 1.17 w/kg. I tried looking for an Apple patent related to this supposed novel antenna design, but couldn’t find anything. What do you think of the iPhone 4’s antenna design? Here is the video segment of Jobs discussing the iPhone 4’s antenna technology:

A company called SkyCross has come up with a novel approach to acheive antenna diversity within a small physical area. SkyCross’s Isolated Mode Antenna Technology (IMAT) uses a single antenna with multiple feeds to acheive diversity. One area where antenna diversity is required is Mulitple Input Mulitple Output (MIMO) systems such as high throughput wireless devices. Before SkyCross annouced their IMAT technology, companies that develop MIMO antenna front-ends for portable electronics have been trying to fit 2 antennas into a small of a space as possible. However, by trying to place two antennas close to each other, undesired mutual coupling will occur and antenna efficiency will also suffer with the reduced antenna size.

SkyCross’s IMAT approach to acheive diversity uses just a SINGLE antenna. By feeding the antenna at two different locations, two different modes are excited, which are independent of each other. Each mode produces a separate, different radiation pattern thus acheiving diversity with high efficiency. This is such a simple solution, but one that will revolutionize