In situations where there's no other way to improve coverage, carriers would probably let their subscribers use the device, Jarich said.

"How aggressive do they want to be in shutting those down and losing customers?" Jarich said. "They would have to tread lightly on that, because there are going to be a bunch of cases where it does make sense."

The June 8 proposal included overall rules for all boosters as well as specific regulations for two classes of devices. The two classes came from separate proposals that came earlier: T-Mobile and manufacturer Nextivity had submitted rules for boosters that only work with one carrier in one location, and Verizon and Wilson had proposed rules that covered other types of boosters.

All four of the major U.S. carriers played some role in the technical work that created the current proposal, Banos said. Sprint said Monday it has participated in the industry discussions and is still evaluating the pending proposals. AT&T executives were not immediately available for comment.

The IDG News Service