How Does Bluetooth Work?
Bluetooth uses short-range radio waves (2.4 GHz) to connect devices directly to each other without a router or network. Devices 'pair' by exchanging security keys, then communicate using low-power signals typically within 30 feet. Bluetooth is designed for low-power, short-range connections like headphones, keyboards, and speakers.
Key Takeaways
- Bluetooth devices contain small radio transceivers that transmit and receive signals in the 2.
- Bluetooth range varies by class: Class 1 (100m), Class 2 (10m, most common), Class 3 (1m).
- Multiple devices can connect to one Bluetooth source, but there are limits (typically 7 for classic Bluetooth).
Explanation
Bluetooth devices contain small radio transceivers that transmit and receive signals in the 2.4 GHz band (same as WiFi, but different protocol). To connect, devices go through 'pairing' - exchanging security keys so they recognize each other. Once paired, devices automatically reconnect when in range.
Bluetooth uses frequency hopping - rapidly switching between 79 channels thousands of times per second - to avoid interference from other devices. This makes connections more reliable despite the crowded 2.4 GHz spectrum. Modern Bluetooth (version 5.0+) has improved range (up to 800 feet in ideal conditions) and speed.
Power efficiency is a key design goal. Bluetooth Low Energy (BLE) uses very little power, making it suitable for devices like fitness trackers and wireless earbuds that need long battery life. This contrasts with WiFi, which uses more power but supports faster data transfers over longer distances.
Things to Know
- Bluetooth range varies by class: Class 1 (100m), Class 2 (10m, most common), Class 3 (1m).
- Multiple devices can connect to one Bluetooth source, but there are limits (typically 7 for classic Bluetooth).
- Bluetooth and WiFi can occasionally interfere since they share the 2.4 GHz band.