Professional signal boosters work by using an external antenna to capture a weak signal, an amplifier to strengthen it, and an internal antenna to rebroadcast it.

For those looking for a "cell phone antenna booster" at Best Buy , it is important to distinguish between , which are effective and sold by major retailers, and booster stickers , which are widely considered ineffective "snake oil" by experts and reviewers. Top-Rated Boosters at Best Buy

What Is a Cell Phone Signal Booster | How It Works & Benefits - T-Mobile