Until now, communications were only skin deep.

The FCC has granted a technical waiver to EnteroMedics, a company that has developed an implanted device used for treating obesity, among other conditions.

The device, to be marketed under the name “Maestro”, stimulates the vagus nerve, and thus intentionally disrupts certain communications between the brain and the digestive tract. One outcome is that people eat less and lose weight.

The device incorporates a small radio antenna surgically planted under the skin. A belt-pack outside the body provides power through the skin (much as an electric toothbrush gets power from its stand), and also provides communications to program the device. In order to keep the device small and simple, the designers arranged for the two functions to share the same radio frequency.

Different FCC rules govern the power and communications functions. But both allow use of the particular frequency the company prefers. Moreover, the power function and the communications function each complies with all the specifics of the relevant rule.

But there is a problem. The two functions comply only when used separately. The permitted levels for power are much higher than for communications. When the two operate together, the communications signal rides on the much stronger power signal, and exceeds the limits in the communications rules.

“So what?” you might say. The purpose of both rules is to prevent interference to other users. The combined device is no more interfering than a version without the communications capability – and a power-only version would comply. For the FCC to block the device because of interplay between the rules would make no sense.

The FCC agrees. In its own words: “[T]here is no more interference potential from allowing the EnteroMedics devices’ communication signal emissions to exceed the limit . . . than if the devices used different circuitry to generate separate compliant power and communication signals that were simultaneously transmitted . . . .” 

The FCC accordingly issued a waiver allowing EnteroMedics to proceed. No doubt their gut told them it was the right thing to do . . .