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This is What's Wrong With iPhone 4's Reception

The iPhone 4's most glaring issue right now is reception. Users have demonstrated that just holding the phone tightly will result in the reception bars dropping dramatically.

Despite all this video evidence, Steve Jobs confidently said, "There are no reception issues. Stay tuned."

Today Apple published a letter on its website explaining what the deal is with the iPhone 4's reception. According to Apple, the problem was due to an inaccurate representation of reception.

Apple says this software inaccuracy has been in the firmware since the original iPhone, and often causes the device to display two more signal bars than it really should.

What Apple didn't share were details of just what was wrong. According to AnandTech's thorough investigation, it was more of a scaling issue than anything else – and the iPhone 4's antenna design is still more susceptible to unintended attenuation and detuning than the previous iPhones or present Android phones.

AnandTech explains:

On iOS, 4 bars begins at around -99 to -101 dBm. Three bars sits around -103 dBm, 2 bars extends down to -107 dBm, and 1 bar is -113 dBm. To give you perspective, for a UMTS "3G" plant, -51 dBm is the best reported signal you can get - it's quite literally standing next to, or under a block away from a tower. At the other extreme, -113 dBm is the worst possible signal you can have before disconnecting entirely. With a few exceptions, signal power as low as -107 dBm is actually perfectly fine for calls and data, and below that is where trouble usually starts. However, you can see just how little dynamic range iOS 4 has for reporting signal; over half of the range of possible signal levels in dBm (from -99 dBm to -51 dBm) is reported as 5 bars.

So, an entire day and more than a quarter tank of gas later, here are the results. Holding the iPhone 4 without a case, in your left hand, crossing the black strip can result in a worst case drop of 24 dB in signal. As we'll show in a second, how you hold the phone makes a huge difference across every smartphone - and we've tested thoroughly in 5 different positions.

In comparison with other phones, the iPhone 4 drops signal more dramatically when held. The flip side of this is that the iPhone 4 also picks up signal better, so overall the reception is superior despite the antenna design flaw.

Check out Apple's full letter below:

Letter from Apple Regarding iPhone 4