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bluetooth mhz range

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Bluetooth operates in the 2.4 GHz ISM (Industrial, Scientific, and Medical) frequency band, specifically in the range from 2.400 GHz to 2.4835 GHz. This frequency band is globally allocated for unlicensed use, which means that Bluetooth-enabled devices can operate without the need for a specific license. The 2.4 GHz band is divided into 79 channels, each 1 MHz wide, but the actual data transmission occurs on 1 MHz or 2 MHz wide channels, depending on the Bluetooth version.

Here's a breakdown of Bluetooth's frequency range:

  1. Frequency Range: 2.400 GHz to 2.4835 GHz
    • This range is divided into 79 channels, each 1 MHz wide.
  2. Channels and Modulation:
    • Bluetooth uses Frequency Hopping Spread Spectrum (FHSS) to avoid interference and improve reliability. It divides the 2.4 GHz band into small frequency channels.
    • Bluetooth Classic (up to version 2.1) uses 79 channels, and Bluetooth Low Energy (Bluetooth LE, from version 4.0 onward) uses 40 channels.
    • Bluetooth devices hop between these channels at a rate of 1600 hops per second for Classic Bluetooth and 2102 hops per second for Bluetooth LE.
  3. Modulation Techniques:
    • Bluetooth uses Gaussian Frequency Shift Keying (GFSK) as its modulation scheme. GFSK is a type of frequency modulation that helps to transmit data efficiently and with minimal interference.
  4. Bluetooth Versions:
    • Bluetooth versions 1.0 and 1.0B had a data rate of 1 Mbps.
    • Bluetooth 2.0 + EDR (Enhanced Data Rate) increased the data rate to 3 Mbps.
    • Bluetooth 3.0 + HS (High Speed) introduced an alternative data transport option using 802.11 Wi-Fi for faster data transfer.
    • Bluetooth 4.0 introduced Bluetooth Low Energy (Bluetooth LE) with reduced power consumption for devices like fitness trackers and other low-power applications.
    • Subsequent versions have further improved data rates, range, and features.
  5. Frequency Interference:
    • Since the 2.4 GHz band is also used by other wireless technologies like Wi-Fi, Zigbee, and microwaves, Bluetooth employs FHSS to navigate between channels, minimizing the chances of interference.

Bluetooth operates in the 2.4 GHz frequency band, and its technical specifications include channel hopping, modulation techniques like GFSK, and varying data rates depending on the Bluetooth version. The use of FHSS and modulation schemes contributes to Bluetooth's ability to provide reliable wireless communication in the presence of other devices operating in the same frequency band.