- Asked 2/20
- 2073 Shrawan · 1+2 marks
- 2072 Chaitra · 2 marks
Spread spectrum frequency hopping in Bluetooth
Short answer
Bluetooth uses frequency hopping spread spectrum across 79 channels, changing 1600 times per second based on the master’s address and clock, with adaptive hopping to avoid interference. Applications include wireless audio, data transfer, peripherals, sensor networks, and medical devices.
What is spread spectrum frequency hopping in Bluetooth? Write the application of Bluetooth.
Frequency hopping spread spectrum (FHSS) in Bluetooth
Spread spectrum spreads a narrow-band signal over a much wider band to resist interference and interception. In frequency hopping, the carrier frequency changes rapidly in a pseudo-random sequence known to both transmitter and receiver.
In Bluetooth:
- The 2.4 GHz ISM band (2402-2480 MHz) is divided into 79 channels of 1 MHz.
- The radio hops 1600 times per second (a new channel every 625 us slot).
- The hop sequence is derived from the master's device address and clock, so all slaves of a piconet follow the same pattern.
- Adaptive frequency hopping (AFH) avoids channels with interference (for example Wi-Fi).
- Benefits: resistance to interference and fading, security, and coexistence of many piconets.
Applications of Bluetooth
- Wireless headsets and speakers; hands-free car kits.
- Data transfer between mobile phones, laptops and PCs; file sharing.
- Wireless keyboards, mice, game controllers and printers.
- Wireless sensor networks and data loggers.
- Medical and fitness devices, smart-home devices, beacons and location services (BLE).
✓ Answer checked by Claude Sonnet 5.5
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