Bluetooth is a robust, user-friendly technology for industrial wireless applications. It offers features to fulfill industrial requirements of flexibility, reliability, security, and coexistence with other technologies like wireless LAN network with low power consumption, fast connection, and easy configuration Bluetooth is ideal for wireless industrial application which it is been performing efficiently. 

Wireless technologies have been in industrial applications for more than 3 decades but the adoption of wireless communication is slow as new technology must work with existing infrastructure or wired networks. Industrial applications involve greater mobility and the possibility to move devices and connect to smartphones freely without constraining cables or bypassing long distances where cables cannot physically fit and are too expensive.

Uses of BLE beacons in the industry have emerged, with the capabilities of indoor localization of personnel, identification, and tracking of assets and equipment, warehouse logistics, access control and management of production processes. A beacon tag, that can be worn an electronic badge for wireless identification of people and assets

Launched in 1998 Bluetooth has become one of the most widely adaptive technology with more than 4 billion devices to be ship in 2020. Most of these devices are consumer electronics but their unique features and accessibility have also found its application in industries that require reliability and robustness.

Bluetooth versions

Bluetooth operates in the 2.4 GHz Industrial, Scientific, and Medical (ISM) radio spectrum. Most of the Bluetooth products are of version v2.1 EDR (Enhanced data rate) which allows higher data throughput. Bluetooth Low Energy (BLE) was introduced in the 4.0 version of the Bluetooth which offers an entirely new protocol stack for the rapid buildup of simple links and longer battery life.

Classic Bluetooth operates in a single-mode implementation. Bluetooth low energy also operates in a single-mode. Sensors like accelerometer, temperature and pressure use BLE are called smart devices. While devices like smartphones and computers are operating in dual-mode are known as Bluetooth Smart Ready devices.

Industrial Challenges for Bluetooth 

Industrial requirements for wireless technologies include:

  • Reliable and robust communication
  • Advanced security features with AFH (adaptive frequency hopping)
  • Similar configuration and operation of tools that are already used in automation.
  • High-temperature range.
  • Coexistence with existing wireless technologies i.e. LAN and Zigbee that also operate in the same frequency band (no interference).

Interference

 The wireless communication used in critical industrial applications must be rugged and reliable. Interference can appear due to high-voltage transmission lines and magnetic fields from electrical motors, etc. Interference can also occur within the wireless technologies that operate in the same radio band. If interference occurs it can affect the connection. Co-existence is a major requirement in industrial wireless technology. Wireless LAN uses 13 overlapping 20-MHz wide channels and two to three non-overlapping channels while Bluetooth uses 79 1-MHz wide channels.

Frequency planning can be used to resolve interference when multiple RF technologies operate in the same band. It is possible to choose channels beforehand that are not to in use to avoid interference with other wireless systems used at the same location. Bluetooth uses the adaptive frequency-hopping (AFH) feature, which detects potential channel interference proximity. If interference is found, the channel is automatically blacklisted.

Range 

Classic Bluetooth supports different output power modes. It can transmit transmission power of up to 100 mW or 20 dBm, which makes a range of more than 1000 m. The transmission power is reduced to the required level for a good connection which prevents unnecessary emission thus reduce possible interference with nearby devices. Bluetooth low energy is limited to a maximum of 10 dBm, with which it can achieve a good transmission range of more than 75 m.

Data security

Bluetooth uses pseudo-random hopping sequence for Frequency Hopping which makes it impossible to access. Besides, the hardware has authentication and 128-bit encryption which makes sit more secure. Bluetooth devices can be made invisible to other devices, which means that hackers are unaware of the device. Moreover, connections can only establish between devices that are already paired.

The choice depends upon the requirement to prioritize between high data throughput, robustness, or low power.

The key advantages of industrial wireless communication:

  • Industrial applications involve greater mobility and the possibility to move devices and connect to smartphones freely without constraining cables.
  • Bypassing long distances where cables cannot physically fit and are too expensive.
  • Fast and easy installation.
  • High flexibility to modify an installation if required.
  • It made easy and safe as personal does not have to be very close to a device for configuration or maintenance.
  • Easy integration of devices in the network.