The listings, including three positions for an "Antenna Engineer - iPad/iPhone" and two for an "iPhone OTA Wireless Systems Engineer," join nine other open positions related to antenna design and testing for iOS devices, with the oldest dating back to last summer.
The most recent postings were highlighted in a blog post by Engadget, which said that Apple began hiring "the same day that we started seeing widespread reporting of the left-handed reception issues."
In addition to the nine antenna-related positions, Apple lists at least 388 open positions related to the iPhone, from Acoustics Engineers to Camera Design Engineers to a Cellular Systems Architect to Cellular Protocol Software Engineers to Embedded Display Driver Engineers to iOS Battery Life Engineers to Analog Sensor Design Engineers, and Bluetooth and WiFi Engineers.
The company is not acknowledging any problem with the iPhone 4 antenna design, and instead noting to customers calling AppleCare that "gripping almost any mobile phone in certain areas will reduce its reception. This is true of the iPhone 4, the iPhone 3GS, and many other phones we have tested. It is a fact of life in the wireless world."
Independent testing by Anandtech found that iPhone 4 does suffer the highest signal drop when holding the phone without a case, compared to the iPhone 3GS and Nexus One, but also noted that the iPhone 4 antenna system is "reception is absolutely definitely improved," over the iPhone 3GS.
A parallel test by Richard Gaywood reported a drop in data throughput when the phone was held without a cover in a way that appeared to allow skin contact to interfere with antenna performance. "This is a factor that doesn't apply to other modern cell phones, because other modern cell phones don't have electrically active components in contact with their bare skin," he wrote.
An iPhone user demonstrated in a Vimeo video that cupping the phone to cause its signal bar to reach zero did not have a discernible effect on the actual quality of the call, suggesting that phone's software may be excessively sensitive in reporting signal drop.
iPhone 4 Reception "Issue" Has No Real Effect on Calls from P S on Vimeo.