The much-publicized reception issues regarding the iPhone 4’s antenna design, where a finger covering the seam on the bottom-left portion of the phone causes significant reception loss, have been verified under rigorously controlled laboratory conditions by the folks at Consumer Reports.

I’ve toured Consumer Reports’ product review facilities in Yonkers, NY. It’s a wonderland of anechoic chambers, call-quality dummies and celltower simulators. In the case of the iPhone, CR fed three different retail-purchased units a pure, simulated AT&T signal, then covered the antenna seam with a finger. They found that a signal loss of up to 20 decibels was common–more than enough to drop your call, especially if the signal is already weak.

This also casts into doubt Apple’s oddly-worded announcement that hoped to explain away the iPhone 4 problems being reported on the internet as a symptom of improper signal-strength calculations–essentially, having the phone show more bars than it actually has. It seems highly doubtful, with testing like Consumer Reports’, that this is the extent of the issue.

Here’s a report from CR’s lab. As you’ll see, they suggest a fix for the antenna short, but it’s not the most aesthetically pleasing:

Consumer Reports